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Marquis de Condorcet

Marie Jean Antoine Nicolas de Caritat, Marquis of Condorcet (17 September 1743 – 29 March 1794), known as Nicolas de Condorcet, was a French political economist and mathematician. His ideas, including support for free markets, public education, constitutional government, and equal rights for women and people of all races, have been said to embody the ideals of the Age of Enlightenment, of which he has been called the "last witness", and Enlightenment rationalism. A critic of the constitution proposed by Marie-Jean Hérault de Séchelles in 1793, the Convention Nationale — and the Jacobin faction in particular — voted to have Condorcet arrested. He died in prison after a period of hiding from the French Revolutionary authorities.

Early years
Condorcet was born in Ribemont (in present-day Aisne), descended from the ancient family of Caritat, who took their title from the town of Condorcet in Dauphiné, of which they were long-time residents. Fatherless at a young age, he was taken care of by his devoutly religious mother who dressed him as a girl till age eight. He was educated at the Jesuit College in Reims and at the Collège de Navarre in Paris, where he quickly showed his intellectual ability and gained his first public distinctions in mathematics. When he was sixteen, his analytical abilities gained the praise of Jean le Rond d'Alembert and Alexis Clairaut; soon, Condorcet would study under d'Alembert.

From 1765 to 1774, he focused on science. In 1765, he published his first work on mathematics, entitled Essai sur le calcul intégral, which was well received, launching his career as a mathematician. He went on to publish more papers, and on 25 February 1769, he was elected to the Académie royale des Sciences.

In 1772, he published another paper on integral calculus. Soon after, he met Jacques Turgot, a French economist, and the two became friends. Turgot became an administrator under King Louis XV in 1772 and Controller-General of Finance under Louis XVI in 1774.

Condorcet worked with Leonhard Euler and Benjamin Franklin. He soon became an honorary member of many foreign academies and philosophic societies, including the American Philosophical Society (1775), the Royal Swedish Academy of Sciences (1785), the American Academy of Arts and Sciences (1792) and also in Prussia and Russia.

His political ideas, many in congruity with Turgot's, were criticized heavily in the English-speaking world, however, most notably by John Adams who wrote two of his principal works of political philosophy to oppose Turgot's and Condorcet's unicameral legislature and radical democracy.

Early political career
In 1774, Condorcet was appointed inspector general of the Paris mint by Turgot. From this point on, Condorcet shifted his focus from the purely mathematical to philosophy and political matters. In the following years, he took up the defense of human rights in general, and of women's and Blacks' rights in particular (an abolitionist, he became active in the Society of the Friends of the Blacks in the 1780s). He supported the ideals embodied by the newly formed United States, and proposed projects of political, administrative and economic reforms intended to transform France.

In 1776, Turgot was dismissed as Controller General. Consequently, Condorcet submitted his resignation as Inspector General of the Monnaie, but the request was refused, and he continued serving in this post until 1791. Condorcet later wrote Vie de M. Turgot (1786), a biography which spoke fondly of Turgot and advocated Turgot's economic theories. Condorcet continued to receive prestigious appointments: in 1777, he became Permanent Secretary of the Académie des Sciences, holding the post until the abolition of the Académie in 1793; and, in 1782, secretary of the Académie française.

Election methods
In 1785, Condorcet published his Essay on the Application of Analysis to the Probability of Majority Decisions, one of his most important works. This work described several now famous results, including Condorcet's jury theorem, which states that if each member of a voting group is more likely than not to make a correct decision, the probability that the highest vote of the group is the correct decision increases as the number of members of the group increases, and Condorcet's paradox, which shows that majority preferences can become intransitive with three or more options – it is possible for a certain electorate to express a preference for A over B, a preference for B over C, and a preference for C over A, all from the same set of ballots.

The paper also outlines a generic Condorcet method, designed to simulate pair-wise elections between all candidates in an election. He disagreed strongly with the alternative method of aggregating preferences put forth by Jean-Charles de Borda (based on summed rankings of alternatives). Condorcet was one of the first to systematically apply mathematics in the social sciences.

He also considered the instant-runoff voting elimination method, as early as 1788, though only to condemn it, for its ability to eliminate a candidate preferred by a majority of voters.

Other works

In 1781, Condorcet wrote a pamphlet, Reflections on Negro Slavery, in which he denounced slavery. In 1786, Condorcet worked on ideas for the differential and integral calculus, giving a new treatment of infinitesimals – a work which apparently was never published. In 1789, he published Vie de Voltaire (1789), which agreed with Voltaire in his opposition to the Church. In the same year he was elected as president of the Society of the Friends of the Blacks and lived in an apartment at Hôtel des Monnaies, Paris, across the Louvre. In 1791, Condorcet, along with Sophie de Grouchy, Thomas Paine, Etienne Dumont, Jacques-Pierre Brissot, and Achilles Duchastellet published a brief journal titled Le Républicain, its main goal being the promotion of republicanism and the rejection of constitutional monarchy. The journal's theme was that any sort of monarchy is a threat to freedom no matter who is leading and that liberty is freedom from domination.

In 1795, Condorcet's book Sketch for a Historical Picture of the Progress of the Human Mind was published after his death by his wife Sophie de Grouchy. It dealt with theoretical thought on perfecting the human mind and analyzing intellectual history based on social arithmetic. Thomas Malthus wrote An Essay on the Principle of Population (1798) partly in response to Condorcet's views on the "perfectibility of society."

Deputy
Condorcet took a leading role when the French Revolution swept France in 1789, hoping for a rationalist reconstruction of society, and championed many liberal causes. As a result, in 1791 he was elected as a Paris representative in the Legislative Assembly, and then became the secretary of the Assembly.

Condorcet was not affiliated with any political party but counted many friends among the Girondins. He distanced himself from them during the National Convention, however, due to his distaste for their factionalism.

In April 1792 Condorcet presented a project for the reformation of the education system, aiming to create a hierarchical system, under the authority of experts, who would work as the guardians of the Enlightenment and who, independent of power, would be the guarantors of public liberties. The project was judged to be contrary to republican and egalitarian virtues, handing the education of the Nation over to an aristocracy of savants, and Condorcet's proposal was not taken up by the Assembly. Several years later, in 1795, when the Thermidorians had gained in strength, the National Convention would adopt an educational plan based on Condorcet's proposal.

He advocated women's suffrage for the new government, writing an article for Journal de la Société de 1789, and by publishing De l'admission des femmes au droit de cité ("For the Admission to the Rights of Citizenship For Women") in 1790.

At the Trial of Louis XVI in December 1792, Condorcet, who opposed the death penalty albeit supporting the trial itself, spoke out against the execution of the King during the public vote at the Convention – he proposed to send the king to work as a slave rower on galley ships.

Condorcet was on the Constitution Committee and was the main author of the Girondin constitutional project. This constitution was not put to a vote. When the Montagnards gained control of the Convention, they wrote their own, the French Constitution of 1793. Condorcet criticized the new work, and as a result, he was branded a traitor. On 3 October 1793, a warrant was issued for Condorcet's arrest.

Arrest and death

The warrant forced Condorcet into hiding. He hid for some months in the house of Mme. Vernet in Paris, where he wrote Esquisse d'un tableau historique des progrès de l'esprit humain (Sketch for a Historical Picture of the Progress of the Human Spirit), which was published posthumously in 1795 and is considered one of the major texts of the Enlightenment and of historical thought. It narrates the history of civilization as one of progress in the sciences, claims an intimate connection between scientific progress and the development of human rights and justice, and outlines the features of a future rational society entirely shaped by scientific knowledge.

On 25 March 1794 Condorcet, convinced he was no longer safe, left his hideout and attempted to flee Paris. He went to seek refuge at the house of Jean-Baptiste Suard, a friend of his with whom he had resided in 1772, but he was refused on the basis that he would be betrayed by one of their residents. Two days later, he was arrested in Clamart and imprisoned in Bourg-la-Reine (or, as it was known during the Revolution, Bourg-l'Égalité, "Equality Borough" rather than "Queen's Borough") where, after another two days, he was found dead in his cell. The most widely accepted theory is that his friend Pierre Jean George Cabanis gave him a poison which he eventually used. However, some historians believe that he may have been murdered (perhaps because he was too loved and respected to be executed). Jean-Pierre Brancourt (in his work L'élite, la mort et la révolution) claims that Condorcet was killed with a mixture of Datura stramonium and opium.

Condorcet was symbolically interred in the Panthéon in 1989, in honour of the bicentennial of the French Revolution and Condorcet's role as a central figure in the Enlightenment. His coffin, however, was empty as his remains, originally interred in the common cemetery of Bourg-la-Reine, were lost during the nineteenth century.

Family
In 1786 Condorcet married Sophie de Grouchy, who was more than twenty years his junior. Sophie, reckoned one of the most beautiful women of the day, became an accomplished salon hostess as Madame de Condorcet, and also an accomplished translator of Thomas Paine and Adam Smith. She was intelligent and well educated, fluent in both English and Italian. The marriage was a strong one, and Sophie visited her husband regularly while he remained in hiding. Although she began proceedings for divorce in January 1794, it was at the insistence of Condorcet and Cabanis, who wished to protect their property from expropriation and to provide financially for Sophie and their young daughter, Louise 'Eliza' Alexandrine.

During his time in hiding, Condorcet penned a poignant letter to his daughter, who was then a toddler, offering his advice and wisdom to her as she grows to become an adult. The letter stands as a testament, not only for the loving hopes he has for his daughter as a father, but also for his egalitarian vision of the rights and opportunities for women in society.

Condorcet was survived by his widow and four-year-old Eliza. Sophie died in 1822, never having remarried, and having published all her husband's works between 1801 and 1804. Her work was carried on by Eliza, wife of former United Irishman Arthur O'Connor. The Condorcet-O'Connors published a revised edition between 1847 and 1849.

Gender equality
Condorcet's work was mainly focused on a quest for a more egalitarian society. This path led him to think and write about gender equality in the Revolutionary context. In 1790, he published "Sur l'admission des femmes au droit de cité" ("On the Admission of Women to the Rights of Citizenship") in which he strongly advocated for women's suffrage in the new Republic as well as the enlargement of basic political and social rights to include women. One of the most famous Enlightenment thinkers at the time, he was one of the first to make such a radical proposal.

'The rights of men stem exclusively from the fact that they are sentient beings, capable of acquiring moral ideas and of reasoning upon them. Since women have the same qualities, they necessarily also have the same rights. Either no member of the human race has any true rights, or else they all have the same ones; and anyone who votes against the rights of another, whatever his religion, colour or sex, automatically forfeits his own.'

Like fellow Enlightenment thinker Jean-Jacques Rousseau in his book Emile ou De l'Education (1762), Condorcet identified education as crucial to the emancipation of individuals. However, where Rousseau endorsed a conservative notion of denying women education and equal rights on account of keeping them tied to the domestic sphere where [according to him] they belonged, Condorcet refused to acquit the inequality between men and women to natural disposition. Instead, he believed that the provision of education to women on par with the education provided to men was the pathway to establishing gender equality. He stated: "I believe that all other differences between men and women are simply the result of education".

Condorcet's whole plea for gender equality is founded on the belief that the attribution of rights and authority comes from a false assumption that men possess reason and women do not. He even goes on to argue that women possess their own form of reason that is different from their male compatriots but by no means lesser however this is nonetheless an artificial difference: "There is more truth in this observation, but it still proves nothing since this difference is caused, not by nature, but by education and society..."

His views on rights that must be afforded to women were not limited to education and citizenship but also social freedoms and protections that included the right for women to plan their own pregnancies, provision of access to birth control, and men's obligation to take responsibility for the welfare of children they have fathered, both legitimate and illegitimate and women's right to seek divorce. He also advocated for the criminalization of rape, declaring that it “violates the property which everyone has in her person”.

Scholars often disagree on the true impact that Condorcet's work had on pre-modern feminist thinking. His detractors point out that, when he was eventually given some responsibilities in the constitutional drafting process, his convictions did not translate into concrete political action and he made limited efforts to push these issues on the agenda. Some scholars on the other hand, believe that this lack of action is not due to the weakness of his commitment but rather to the political atmosphere at the time and the absence of political appetite for gender equality on the part of decision-makers. Along with authors such as Mary Wollstonecraft, d'Alembert or Olympe de Gouges, Condorcet made a lasting contribution to the pre-feminist debate.

The idea of progress
Condorcet's Sketch for a Historical Picture of the Progress of the Human Spirit (1795) was perhaps the most influential formulation of the idea of progress ever written. It made the Idea of Progress a central concern of Enlightenment thought. He argued that expanding knowledge in the natural and social sciences would lead to an ever more just world of individual freedom, material affluence, and moral compassion. He argued for three general propositions: that the past revealed an order that could be understood in terms of the progressive development of human capabilities, showing that humanity's "present state, and those through which it has passed, are a necessary constitution of the moral composition of humankind"; that the progress of the natural sciences must be followed by progress in the moral and political sciences "no less certain, no less secure from political revolutions"; that social evils are the result of ignorance and error rather than an inevitable consequence of human nature. He was innovative in suggesting that scientific medicine might in the future significantly extend the human life span, perhaps even indefinitely, such that future humans only die of accident, murder and suicide rather than simply old age or disease. Nick Bostrom has thus described him as an early transhumanist.

Condorcet's writings were a key contribution to the French Enlightenment, particularly his work on the Idea of Progress. Condorcet believed that through the use of our senses and communication with others, knowledge could be compared and contrasted as a way of analyzing our systems of belief and understanding. None of Condorcet's writings refer to a belief in a religion or a god who intervenes in human affairs. Condorcet instead frequently had written of his faith in humanity itself and its ability to progress with the help of philosophers such as Aristotle. Through this accumulation and sharing of knowledge he believed it was possible for anybody to comprehend all the known facts of the natural world. The enlightenment of the natural world spurred the desire for enlightenment of the social and political world. Condorcet believed that there was no definition of the perfect human existence and thus believed that the progression of the human race would inevitably continue throughout the course of our existence. He envisioned man as continually progressing toward a perfectly utopian society. He believed in the great potential towards growth that man possessed.

However, Condorcet stressed that for this to be a possibility man must unify regardless of race, religion, culture or gender. To this end, he became a member of the French Société des Amis des Noirs (Society of the Friends of the Blacks). He wrote a set of rules for the Society of the Friends of the Blacks which detailed the reasoning and goals behind the organization along with describing the injustice of slavery and put in a statement calling for the abolition of the slave trade as the first step to true abolition.

Condorcet was also a strong proponent of women's civil rights. He claimed that women were equal to men in nearly every aspect and asked why then should they be debarred from their fundamental civil rights; the few differences that existed were due to the fact that women were limited by their lack of rights. Condorcet even mentioned several women who were more capable than average men, such as Queen Elizabeth and Maria-Theresa. Furthermore, as he argues for the civil, political, and educational rights of women, Condorcet boldly challenges that unless women's natural inferiority to men could be proven, the denial of the aforementioned rights is an "act of tyranny" constituted by the newly formed French nation.

About Islam and China he wrote: "the religion of Mohammed, the simplest in its dogmas, the least absurd in its practices, the most tolerant in its principles, seems to condemn to eternal slavery, to incurable stupidity, this entire vast portion of the Earth where it has extended its empire; while we will see the genius of science and freedom shine beneath the most absurd superstitions, in the midst of the most barbaric intolerance. China offers us the same phenomenon, although the effects of this stupefying poison have been less fatal."

Civic duty
For Condorcet's republicanism the nation needed enlightened citizens and education needed democracy to become truly public. Democracy implied free citizens, and ignorance was the source of servitude. Citizens had to be provided with the necessary knowledge to exercise their freedom and understand the rights and laws that guaranteed their enjoyment. Although education could not eliminate disparities in talent, all citizens, including women, had the right to free education. In opposition to those who relied on revolutionary enthusiasm to form the new citizens, Condorcet maintained that revolution was not made to last and that revolutionary institutions were not intended to prolong the revolutionary experience but to establish political rules and legal mechanisms that would insure future changes without revolution. In a democratic city there would be no Bastille to be seized. Public education would form free and responsible citizens, not revolutionaries.

Evaluation
Rothschild (2001) argues that Condorcet has been seen since the 1790s as the embodiment of the cold, rational Enlightenment. However she suggests his writings on economic policy, voting, and public instruction indicate different views both of Condorcet and of the Enlightenment. Condorcet was concerned with individual diversity; he was opposed to proto-utilitarian theories; he considered individual independence, which he described as the characteristic liberty of the moderns, to be of central political importance; and he opposed the imposition of universal and eternal principles. His efforts to reconcile the universality of some values with the diversity of individual opinions are of continuing interest. He emphasizes the institutions of civilized or constitutional conflict, recognizes conflicts or inconsistencies within individuals, and sees moral sentiments as the foundation of universal values. His difficulties call into question some familiar distinctions, for example between French, German, and English-Scottish thought, and between the Enlightenment and the counter-Enlightenment. There was substantial continuity between Condorcet's criticism of the economic ideas of the 1760s and the liberal thought of the early 19th century.

The Lycée Condorcet in the rue du Havre, in the 9th arrondissement of Paris, is named in his honour, as are streets in many French cities.

Publications

 * Essai sur le calcul intégral, 1765
 * Rapport sur le choix d'une unité de mesure, lu à l'Academie des sciences le 19 mars 1791 / imprimé par ordre de l'Assemblée nationale. With Jean-Charles de Borda.
 * Lettres d'un théologien à l'auteur du Dictionnaire des trois siècles, 1774
 * Réflexions sur l'esclavage des nègres, 1781. Under the pseudonym M. Schwartz
 * Mémoire sur le calcul des probabilités, in Mémoires de l’Académie royale des sciences. 1781–1784
 * Éloge de M. d'Alembert, lu dans l'Assemblée publique de l'Académie des sciences, le 21 Avril 1784. A Paris: chez Moutard, 1784
 * Essai sur l'application de l'analyse à la probabilité des décisions rendus à la pluralité des voix. Paris: Royale, 1785
 * De l’influence de la révolution d’Amérique sur l’Europe. 1786
 * Vie de Monsieur Turgot. Londres, 1786
 * Réflexions d'un citoyen, sur la révolution de 1788. Londres, 1788
 * Sur le choix des ministres, 1789
 * Au corps électoral sur Esclavage des Noirs. 1789
 * Déclaration des droits. 1789
 * Sur l’admission des femmes au droit de cité. 1790
 * Réflexions sur la révolution de 1688, et sur celle du 10 août 1792, 1792
 * Adresse aux Bataves, 1792
 * Vie de Voltaire. Paris : Renouard, 1822. Contains also: Mémoires pour servir à la vie de M. de Voltaire / écrits par lui-m^eme. Commentaire historique sur les œuvres de l'auteur de la Henriade. Choix de pièces justificatives pour La vie de Voltaire
 * Correspondance inédite de Condorcet et de Turgot: 1770-1779. Paris: Charavay Frères, 1883
 * Œuvres complètes, Paris, 1804. 21 delen
 * Tome premier. Eloges des académiciens de l'Académie Royale de Sciences, morts depuis l'an 1666, jusqu'en 1699
 * Tome II: Mélanges de littérature et de philosophie Tome II. Éloges des académiciens de l'Académie Royale de Sciences, morts depuis l'an 1771
 * Tome III: Mélanges de littérature et de philosophie tome III. Éloges des académiciens de l'Académie Royale de Sciences, morts depuis l'an 1783
 * Tome IV: Mélanges de littérature et de philosophie. Eloges des académiciens de l'Académie Royale de Sciences, morts depuis l'an 1787; suivvis de cuex de Michel de l'hôpital et de Blaise Pascal
 * Tome V: Vie de M. Turgot, publiée en 1786
 * Tome VI: Mélanges de littérature et de philosophie. Vie de Voltaire, suivi des advertissements et notes ...
 * Tome septième: Economie politique et politique tome I. Réflexions sur la jurisprudence criminelle. 1775. 1847
 * Tome VIII: Mélanges de littérature et de philosophie. Exquisse d'un tableau historique des progrès de l'esprit humaine. Premiere partie
 * Tome IX: Mélanges de littérature et de philosophie Tome IX. Sur l'instruction publique
 * Tome X: Mélanges de littérature et de philosophie Tome X. Lettres d'un théologien a l'auteur des trois siècles
 * Tome XI: Mélanges de politique tome XI. Réflexions sur la jurisprudence criminelle
 * Tome XII: Lettres d'un bourgeois de New-Heaven a un citoyen de Virginie ...
 * Tome XIII: Melanges de politique. Sur les assemblées provinciales. Première partie
 * Tome XIV: Melanges de politique. Sur les assemblées provinciales. Seconde partie
 * Tome XVI: Fragmentt sur la liberté de la presse
 * Tome XVII: Mélanges de politique tome XVII. De l'influence d'un monarque et d'une cour . Sur les moers d'un peuple libre
 * Tome XVIII: Sur le sens du mot révolutionnaire
 * Tome XIX: Lettre d'un laboureur de Picardie, A.M.N.***
 * Tome XX: Mélanges d'economie politique Tome XX. Plan d'un emprunt publique, avec des hypothèques spéciales
 * Tome XXI: Sur les caisses d'accumulation
 * Tome XX: Mélanges d'economie politique Tome XX. Plan d'un emprunt publique, avec des hypothèques spéciales
 * Tome XXI: Sur les caisses d'accumulation

Novels

 *  City of Darkness, City of Light by Marge Piercy

Movies

 * Flashback (2021)

title: Marquis de Condorcet


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British North America Acts

The British North America Acts, 1867–1975, are a series of acts of Parliament that were at the core of the Constitution of Canada. Most were enacted by the Parliament of the United Kingdom and some by the Parliament of Canada. Some of the acts were repealed in Canada by the Constitution Act, 1982. The rest were renamed the Constitution Acts and amended, with those changes having effect only in Canada. The Canadian versions of the Constitution Acts are part of the Constitution of Canada, and can be amended only in Canada.

The British versions of the acts which remain in force in Britain are ordinary British statutes. They can be amended by the British Parliament, but those amendments would not have any effect in Canada. They retain their original names and do not include any amendments made after 1964.

As used in these acts, the term "British North America" (BNA) originally referred to the British colonies in North America which formed Confederation in 1867: the Province of Canada (which became the provinces of Ontario and Quebec), Nova Scotia, and New Brunswick. The 1867 act also envisaged that specific other colonies might join Confederation in the future: British Columbia,  Newfoundland, Prince Edward Island,  Rupert's Land, and the North-Western Territory. Even after the creation of Canada in 1867, the subsequent acts listed in this article continued to use the term "British North America", but the term then applied only to Canada.

Constitutional changes
Canada dates its history as a country to the British North America Act, 1867, which came into effect on July 1, 1867. However, Canada was not established as fully independent, since the United Kingdom retained legislative control over Canada and full control over Canadian foreign policy. Canada did not have any foreign embassies until the first one was established in Washington, D.C., in 1926. Until 1949, changes to the British North America Acts could be made only by the British Parliament. The British North America (No. 2) Act, 1949, gave the Parliament of Canada the power to make limited constitutional amendments, but full Canadian control over the constitution was not achieved until the passage of the Canada Act 1982. This long delay was in large part due to the inability to agree upon a procedure for making constitutional amendments that was acceptable to all of the provinces, in particular the Province of Quebec.

Because of this, all British North America Acts dated before 1949 were passed by the British Parliament, while some of those dated after 1949 were passed by the Canadian Parliament. When Canada patriated its constitution with the passage of the Canada Act 1982, most of the British North America Acts were renamed as "Constitution Acts" in Canada, while a few of the acts were repealed as no longer having any relevance. The acts are collectively called the Constitution Acts 1867 to 1982.

French-language versions
The fifteen BNA Acts enacted by the United Kingdom Parliament do not have official French-language versions. Only the English version is official. The five BNA Acts enacted by the Canadian Parliament do have official French-language versions, and the English-language and French-language versions are equally authoritative (as with all legislation enacted by the Canadian Parliament).

The French Constitutional Drafting Committee produced translations of all the British North America Acts, pursuant to section 55 of the Constitution Act, 1982, but these were never enacted by the federal and provincial governments through the constitutional amending process to make them official.

Individual Acts
The different Acts of this series are distinguished by appending the year of their enactment. BNA Acts were passed in 1867, 1871, 1886, 1907, 1915, 1916*, 1930, 1940, 1943*, 1946*, 1949, 1949 (No. 2)*, 1951*, 1952*, 1960, 1964, 1965, 1974, 1975 and 1975 (No. 2). Those marked with (*) were repealed in Canada in 1982, but are still in force in Britain. Five of the British North America Acts were enacted by the Parliament of Canada; namely those of 1952, 1965, 1974, 1975, and 1975 (No. 2). The other fifteen were enacted by the Imperial Parliament in London.

The first Act, the British North America Act, 1867, created the self-governing (internally) Dominion of Canada. The remaining acts dealt with a variety of topics, though the majority were concerned with modifying the representation in Parliament or in the Senate of Canada as the country enlarged and changed (1886, 1915, 1943, 1946, 1952, 1974, 1975, 1975 (No. 2)), adding the newer Provinces of Manitoba, British Columbia, Saskatchewan, Alberta, and Newfoundland. Other topics include modifying the country's boundaries (1871, 1949), transfer payments (1907), temporary changes due to two world wars (1916, 1943), federal-provincial powers (1930, 1964), power over changes in the constitution (1949 (No. 2)), the creation of new social programs (1951, 1964), and mandatory retirement ages in the Canadian government (1960, 1965)

British North America Act, 1867
The British North America Act, 1867, also known as the BNA Act, comprises a major part of the Constitution of Canada. The act entails the original creation of a federal dominion and sets the framework for much of the operation of the Government of Canada, including its federal structure, the House of Commons of Canada, the Senate, the justice system, and the taxation system. In 1982, this Act was renamed the Constitution Act, 1867, with the patriation of the constitution (having originally been enacted by the Parliament of the United Kingdom). Amendments were also made at this time: section 92A was added, giving the provinces greater control over non-renewable natural resources.

British North America Act, 1871
This Act gave Canada the power to establish new provinces and territories and to change provincial boundaries with the affected province's consent. The act recognized the creation of the province of Manitoba, and also the incorporation of Rupert's Land and the Northwest Territories into Canada. This Act also allowed the Canadian parliament and the legislatures of Ontario and Quebec to redraw the boundaries of the province of Ontario and the province of Quebec in order to include parts of these land acquisitions, specifically around Hudson Bay and James Bay. In 1982, this Act was renamed the Constitution Act, 1871.

British North America Act, 1886
This Act gave parliament the authority to allow the Territories of Canada to have representation in the Canadian Senate and Canadian House of Commons. In 1982, this Act was renamed the Constitution Act, 1886.

British North America Act, 1907
This Act regulated transfer payments by the federal government to the smaller provinces to support their legislatures and governments. The funds transferred were set at between $100,000 and $250,000 depending on the province's population with an extra $100,000 a year for ten years to British Columbia. In 1982, this Act was renamed the Constitution Act, 1907.

British North America Act, 1915
This Act expanded the Senate of Canada by giving the Western Canadian provinces 24 senators, the same number that had been guaranteed to Ontario, Quebec, and the Maritime Provinces. This Act also guaranteed Newfoundland six senators should that British domain ever join the Confederation – which it did in 1949. Finally, this act amended section 51 of the British North America Act of 1867 to guarantee that no province would have fewer members of the House of Commons than of the senate. In 1982, this Act was renamed the Constitution Act, 1915.

British North America Act, 1916
This Act extended the duration of the 12th Canadian Parliament through October 1917, beyond the normal maximum of five years. The extension was carried out due to World War I. This Act was repealed by the Statute Law Revision Act 1927.

British North America Act, 1930
This Act gave the newer provinces of British Columbia, Alberta, Manitoba, and Saskatchewan rights over certain natural resources found in federally controlled lands. In 1982, this Act was renamed the Constitution Act, 1930.

British North America Act, 1940
This Act gave the Federal government jurisdiction over unemployment insurance, thus allowing such a program to be established on a national level. An earlier attempt to create an Employment and Social Insurance Act during the Great Depression had been ruled to be unconstitutional, since unemployment assistance was judged by the courts to be a provincial responsibility. In 1982, this Act was renamed the Constitution Act, 1940.

British North America Act, 1943
This Act delayed redistribution of seats in the Canadian House of Commons until the end of World War II. This Act was repealed in Canada 1982, as being completely outdated and obsolete.

British North America Act, 1946
This Act adjusted the formula for distributing seats in the Canadian House of Commons among the provinces and territories. It was repealed in Canada in 1982, as having been superseded.

British North America Act, 1949
This Act allowed for the entry of Newfoundland as Canada's tenth province. This Act was renamed the Newfoundland Act when the Canadian Constitution was patriated from the United Kingdom in 1982.

This Act should not be confused with the British North America (No. 2) Act 1949 (see below).

British North America (No. 2) Act, 1949
This Act granted Canada limited powers to amend its own constitution. The Parliament of Canada was thereafter allowed to amend the Canadian constitution in many areas of its own jurisdiction without first obtaining the consent of the British Parliament. However, the approval of the British Parliament was still needed for wider constitutional changes, such as those involving areas of provincial and federal responsibilities. Therefore, this Act can at best be considered a "partial patriation" of the Canadian Constitution.

This Act was repealed in 1982 with the full patriation of the Canadian Constitution from the United Kingdom, and with the incorporation of a new, comprehensive procedure for amending the Constitution.

This Act is not to be confused with the British North America Act, 1949 (see above).

British North America Act, 1951
This Act gave the Federal government the power to pass legislation concerning old age pensions, while also recognizing the rights of provincial legislatures to do so. While the Canadian Parliament had established an old age pension program in 1927, this was administered by the provinces and jointly funded by them. This Act of the British Parliament allowed the Federal government of Canada to administer and operate its own pension plan and allowed it to pass the Old Age Security Act. This Act was repealed in Canada in 1982, since it had been superseded.

British North America Act, 1952
This was the first of the British North America Acts to be enacted by the Canadian Parliament (rather than by the British Parliament). That had been made possible under the provisions of the British North America (No. 2) Act, 1949.

This Act changed the number of seats in the House of Commons and it also limited the number of seats that a province could lose due to redistribution based on the national census to 15% of its previous number of seats. This Act also gave the Yukon Territory its own Member of Parliament. This Act was repealed in 1982 as having become obsolete and superseded.

British North America Act, 1960
This Act instituted a mandatory retirement age of 75 for all superior court judges. In 1982, this Act was renamed the Constitution Act, 1960.

British North America Act, 1964
This Act extended the federal government's jurisdiction over pensions to include those of survivor's benefits and disability benefits while continuing to allow the provinces to have their own pension programs. This amendment to the BNA Act made the Canada Pension Plan possible. In 1982, this Act was renamed the Constitution Act, 1964.

This was the last time that the British Parliament enacted legislation on Canada's behalf before the patriation of the Canadian constitution in 1982. The inability of Canada to amend its own constitution already seemed antiquated in 1964. In the debate, a British MP called it an "astonishing and absurd historical anomaly" that "the Canadian Parliament is the only Parliament in the Commonwealth that has to come to us to ask permission to legislate about domestic matters."

British North America Act, 1965
This was the second of the British North America Acts to be enacted by the Parliament of Canada. This was made possible by the provisions of the British North America (No. 2) Act, 1949.

This Act established a mandatory retirement age of 75 for all members who were appointed to the Canadian Senate in future. Those who had been appointed before the passage of this Act were exempted. In 1982, this Act was renamed the Constitution Act, 1965.

British North America Act, 1974
This was the third of the British North America Acts to be enacted by the Parliament of Canada. This had been made possible by the provisions of the British North America (No. 2) Act, 1949.

It was originally titled Representation Act, 1974, then changed to British North America Act, 1974 in 1977 before changing to Constitution Act, 1974 in 1982.

This Act changed the rules for the redistribution of seats in the House of Commons of Canada so that Quebec was allocated the fixed number of 75 seats, while the number of seats allocated to each of the other provinces would always be determined based upon the sizes of their populations in comparison with that of Quebec. However, the Provinces continued to be guaranteed to have at least as many members of the House of Commons as they had Senators. In 1982, this Act was renamed the Constitution Act, 1974.

British North America Act, 1975
This was the fourth of the British North America Acts to be enacted by the Parliament of Canada. This had been made possible by the provisions of the British North America (No. 2) Act, 1949.

It was originally titled Northwest Territories Representation Act, then changed to British North America Act (No 1), 1975 in 1977 before changing to Constitution Act (No. 1), 1975 in 1982.

This Act increased the number of representatives from the Northwest Territories in the Canadian House of Commons, from one to two members. In 1982, this Act was renamed the Constitution Act (No. 1), 1975.

British North America Act (No. 2), 1975
This was the fifth of the British North America Acts to be enacted by the Parliament of Canada.

This Act increased the number of seats in the Canadian Senate from 102 to 104, and it allocated one seat to the Yukon Territory and one to the Northwest Territories. In 1982, this Act was renamed the Constitution Act (No. 2), 1975.

Canada Act 1982
This final Act of the British Parliament regarding Canada had a different name, since it renamed all the unrepealed earlier British North America Acts, amended some of them, and repealed all others, patriated all remaining legislative and constitutional powers to Canada, and included the Constitution Act, 1982 as its schedule. It is the only UK legislation to be enacted in both English and French, although the French version only has equal authority in Canada.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: British North America Acts


text:
Turtle

Turtles are reptiles of the order Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked turtles), which differ in the way the head retracts. There are 360 living and recently extinct species of turtles, including land-dwelling tortoises and freshwater terrapins. They are found on most continents, some islands and, in the case of sea turtles, much of the ocean. Like other amniotes (reptiles, birds, and mammals) they breathe air and do not lay eggs underwater, although many species live in or around water.

Turtle shells are made mostly of bone; the upper part is the domed carapace, while the underside is the flatter plastron or belly-plate. Its outer surface is covered in scales made of keratin, the material of hair, horns, and claws. The carapace bones develop from ribs that grow sideways and develop into broad flat plates that join up to cover the body. Turtles are ectotherms or "cold-blooded", meaning that their internal temperature varies with their direct environment. They are generally opportunistic omnivores and mainly feed on plants and animals with limited movements. Many turtles migrate short distances seasonally. Sea turtles are the only reptiles that migrate long distances to lay their eggs on a favored beach.

Turtles have appeared in myths and folktales around the world. Some terrestrial and freshwater species are widely kept as pets. Turtles have been hunted for their meat, for use in traditional medicine, and for their shells. Sea turtles are often killed accidentally as bycatch in fishing nets. Turtle habitats around the world are being destroyed. As a result of these pressures, many species are extinct or threatened with extinction.

Naming and etymology
The word turtle is borrowed from the French word tortue or tortre 'turtle, tortoise'. It is a common name and may be used without knowledge of taxonomic distinctions. In North America, it may denote the order as a whole. In Britain, the name is used for sea turtles as opposed to freshwater terrapins and land-dwelling tortoises. In Australia, which lacks true tortoises (family Testudinidae), non-marine turtles were traditionally called tortoises, but more recently turtle has been used for the entire group.

The name of the order, Testudines, is based on the Latin word testudo 'tortoise'; and was coined by German naturalist August Batsch in 1788. The order has also been historically known as Chelonii (Latreille 1800) and Chelonia (Ross and Macartney 1802), which are based on the Ancient Greek word χελώνη 'tortoise'. Testudines is the official order name due to the principle of priority. The term chelonian is used as a formal name for members of the group.

Size
The largest living species of turtle (and fourth-largest reptile) is the leatherback turtle, which can reach over 2.7 m in length and weigh over 500 kg. The largest known turtle was Archelon ischyros, a Late Cretaceous sea turtle up to 4.5 m long, 5.25 m wide between the tips of the front flippers, and estimated to have weighed over 2200 kg. The smallest living turtle is Chersobius signatus of South Africa, measuring no more than 10 cm in length and weighing 172 g.

Shell

The shell of a turtle is unique among vertebrates and serves to protect the animal and provide shelter from the elements. It is primarily made of 50–60 bones and consists of two parts: the domed, dorsal (back) carapace and the flatter, ventral (belly) plastron. They are connected by lateral (side) extensions of the plastron.

The carapace is fused with the vertebrae and ribs while the plastron is formed from bones of the shoulder girdle, sternum, and gastralia (abdominal ribs). During development, the ribs grow sideways into a carapacial ridge, unique to turtles, entering the dermis (inner skin) of the back to support the carapace. The development is signaled locally by proteins known as fibroblast growth factors that include FGF10. The shoulder girdle in turtles is made up of two bones, the scapula and the coracoid. Both the shoulder and pelvic girdles of turtles are located within the shell and hence are effectively within the rib cage. The trunk ribs grow over the shoulder girdle during development. The shell is covered in epidermal (outer skin) scales known as scutes that are made of keratin, the same substance that makes up hair and fingernails. Typically, a turtle has 38 scutes on the carapace and 16 on the plastron, giving them 54 in total. Carapace scutes are divided into "marginals" around the margin and "vertebrals" over the vertebral column, though the scute that overlays the neck is called the "cervical". "Pleurals" are present between the marginals and vertebrals. Plastron scutes include gulars (throat), humerals, pectorals, abdominals, and anals. Side-necked turtles additionally have "intergular" scutes between the gulars. Turtle scutes are usually structured like mosaic tiles, but some species, like the hawksbill sea turtle, have overlapping scutes on the carapace.

The shapes of turtle shells vary with the adaptations of the individual species, and sometimes with sex. Land-dwelling turtles are more dome-shaped, which appears to make them more resistant to being crushed by large animals. Aquatic turtles have flatter, smoother shells that allow them to cut through the water. Sea turtles in particular have streamlined shells that reduce drag and increase stability in the open ocean. Some turtle species have pointy or spiked shells that provide extra protection from predators and camouflage against the leafy ground. The lumps of a tortoise shell can tilt its body when it gets flipped over, allowing it to flip back. In male tortoises, the tip of the plastron is thickened and used for butting and ramming during combat.

Shells vary in flexibility. Some species, such as box turtles, lack the lateral extensions and instead have the carapace bones fully fused or ankylosed together. Several species have hinges on their shells, usually on the plastron, which allow them to expand and contract. Softshell turtles have rubbery edges, due to the loss of bones. The leatherback turtle has hardly any bones in its shell, but has thick connective tissue and an outer layer of leathery skin.

Head and neck
The turtle's skull is unique among living amniotes (which includes reptiles, birds and mammals); it is solid and rigid with no openings for muscle attachment (temporal fenestrae). Muscles instead attach to recesses in the back of the skull. Turtle skulls vary in shape, from the long and narrow skulls of softshells to the broad and flattened skull of the mata mata. Some turtle species have developed large and thick heads, allowing for greater muscle mass and stronger bites.

Turtles that are carnivorous or durophagous (eating hard-shelled animals) have the most powerful bites. For example, the durophagous Mesoclemmys nasuta has a bite force of 432 lbf. Species that are insectivorous, piscivorous (fish-eating), or omnivorous have lower bite forces. Living turtles lack teeth but have beaks made of keratin sheaths along the edges of the jaws. These sheaths may have sharp edges for cutting meat, serrations for clipping plants, or broad plates for breaking mollusks. Sea turtles, and several extinct forms, have evolved a bony secondary palate which completely separates the oral and nasal cavities.

The necks of turtles are highly flexible, possibly to compensate for their rigid shells. Some species, like sea turtles, have short necks while others, such as snake-necked turtles, have long ones. Despite this, all turtle species have eight neck vertebrae, a consistency not found in other reptiles but similar to mammals. Some snake-necked turtles have both long necks and large heads, limiting their ability to lift them when not in water. Some turtles have folded structures in the larynx or glottis that vibrate to produce sound. Other species have elastin-rich vocal cords.

Limbs and locomotion
Due to their heavy shells, turtles are slow-moving on land. A desert tortoise moves at only 0.22 –. By contrast, sea turtles can swim at 30 km/h. The limbs of turtles are adapted for various means of locomotion and habits and most have five toes. Tortoises are specialized for terrestrial environments and have column-like legs with elephant-like feet and short toes. The gopher tortoise has flattened front limbs for digging in the substrate. Freshwater turtles have more flexible legs and longer toes with webbing, giving them thrust in the water. Some of these species, such as snapping turtles and mud turtles, mainly walk along the water bottom, as they would on land. Others, such as terrapins, swim by paddling with all four limbs, switching between the opposing front and hind limbs, which keeps their direction stable.

Sea turtles and the pig-nosed turtle are the most specialized for swimming. Their front limbs have evolved into flippers while the shorter hind limbs are shaped more like rudders. The front limbs provide most of the thrust for swimming, while the hind limbs serve as stabilizers. Sea turtles such as the green sea turtle rotate the front limb flippers like a bird's wings to generate a propulsive force on both the upstroke and on the downstroke. This is in contrast to similar-sized freshwater turtles (measurements having been made on young animals in each case) such as the Caspian turtle, which uses the front limbs like the oars of a rowing boat, creating substantial negative thrust on the recovery stroke in each cycle. In addition, the streamlining of the marine turtles reduces drag. As a result, marine turtles produce a propulsive force twice as large, and swim six times as fast, as freshwater turtles. The swimming efficiency of young marine turtles is similar to that of fast-swimming fish of open water, like mackerel.

Compared to other reptiles, turtles tend to have reduced tails, but these vary in both length and thickness among species and between sexes. Snapping turtles and the big-headed turtle have longer tails; the latter uses it for balance while climbing. The cloaca is found underneath and at the base, and the tail itself houses the reproductive organs. Hence, males have longer tails to contain the penis. In sea turtles, the tail is longer and more prehensile in males, who use it to grasp mates. Several turtle species have spines on their tails.

Senses

Turtles make use of vision to find food and mates, avoid predators, and orient themselves. The retina's light-sensitive cells include both rods for vision in low light, and cones with three different photopigments for bright light, where they have full-color vision. There is possibly a fourth type of cone that detects ultraviolet, as hatchling sea turtles respond experimentally to ultraviolet light, but it is unknown if they can distinguish this from longer wavelengths. A freshwater turtle, the red-eared slider, has an exceptional seven types of cone cell.

Sea turtles orient themselves on land by night, using visual features detected in dim light. They can use their eyes in clear surface water, muddy coasts, the darkness of the deep ocean, and also above water. Unlike in terrestrial turtles, the cornea (the curved surface that lets light into the eye) does not help to focus light on the retina, so focusing underwater is handled entirely by the lens, behind the cornea. The cone cells contain oil droplets placed to shift perception toward the red part of the spectrum, improving color discrimination. Visual acuity, studied in hatchlings, is highest in a horizontal band with retinal cells packed about twice as densely as elsewhere. This gives the best vision along the visual horizon. Sea turtles do not appear to use polarized light for orientation as many other animals do. The deep-diving leatherback turtle lacks specific adaptations to low light, such as large eyes, large lenses, or a reflective tapetum. It may rely on seeing the bioluminescence of prey when hunting in deep water.

Turtles have no ear openings; the eardrum is covered with scales and encircled by a bony otic capsule, which is absent in other reptiles. Their hearing thresholds are high in comparison to other reptiles, reaching up to 500 Hz in air, but underwater they are more attuned to lower frequencies. The loggerhead sea turtle has been shown experimentally to respond to low sounds, with maximal sensitivity between 100 and 400 Hz.

Turtles have olfactory (smell) and vomeronasal receptors along the nasal cavity, the latter of which are used to detect chemical signals. Experiments on green sea turtles showed they could learn to respond to a selection of different odorant chemicals such as triethylamine and cinnamaldehyde, which were detected by olfaction in the nose. Such signals could be used in navigation.

Breathing
The rigid shell of turtles is not capable of expanding and making room for the lungs, as in other amniotes, so they have had to evolve special adaptations for respiration. The lungs of turtles are attached directly to the carapace above while below, connective tissue attaches them to the organs. They have multiple lateral (side) and medial (middle) chambers (the numbers of which vary between species) and one terminal (end) chamber.

The lungs are ventilated using specific groups of abdominal muscles attached to the organs that pull and push on them. Specifically, it is the turtle's large liver that compresses the lungs. Underneath the lungs, in the coelomic cavity, the liver is connected to the right lung by the root, and the stomach is directly attached to the left lung, and to the liver by a mesentery. When the liver is pulled down, inhalation begins. Supporting the lungs is a wall or septum, which is thought to prevent them from collapsing. During exhalation, the contraction of the transversus abdominis muscle propels the organs into the lungs and expels air. Conversely, during inhalation, the relaxing and flattening of the oblique abdominis muscle pulls the transversus back down, allowing air back into the lungs.

Although many turtles spend large amounts of their lives underwater, all turtles breathe air and must surface at regular intervals to refill their lungs. Depending on the species, immersion periods vary between a minute and an hour. Some species can respire through the cloaca, which contains large sacs that are lined with many finger-like projections that take up dissolved oxygen from the water.

Circulation

Turtles share the linked circulatory and pulmonary (lung) systems of vertebrates, where the three-chambered heart pumps deoxygenated blood through the lungs and then pumps the returned oxygenated blood through the body's tissues. The cardiopulmonary system has both structural and physiological adaptations that distinguish it from other vertebrates. Turtles have a large lung volume and can move blood through non-pulmonary blood vessels, including some within the heart, to avoid the lungs while they are not breathing. They can hold their breath for much longer periods than other reptiles and they can tolerate the resulting low oxygen levels. They can moderate the increase in acidity during anaerobic (non-oxygen-based) respiration by chemical buffering and they can lie dormant for months, in aestivation or brumation.

The heart has two atria but only one ventricle. The ventricle is subdivided into three chambers. A muscular ridge enables a complex pattern of blood flow so that the blood can be directed either to the lungs via the pulmonary artery, or to the body via the aorta. The ability to separate the two outflows varies between species. The leatherback has a powerful muscular ridge enabling almost complete separation of the outflows, supporting its actively swimming lifestyle. The ridge is less well developed in freshwater turtles like the sliders (Trachemys).

Turtles are capable of enduring periods of anaerobic respiration longer than many other vertebrates. This process breaks down sugars incompletely to lactic acid, rather than all the way to carbon dioxide and water as in aerobic (oxygen-based) respiration. They make use of the shell as a source of additional buffering agents for combating increased acidity, and as a sink for lactic acid.

Osmoregulation
In sea turtles, the bladder is one unit and in most freshwater turtles, it is double-lobed. Sea turtle bladders are connected to two small accessory bladders, located at the sides to the neck of the urinary bladder and above the pubis. Arid-living tortoises have bladders that serve as reserves of water, storing up to 20% of their body weight in fluids. The fluids are normally low in solutes, but higher during droughts when the reptile gains potassium salts from its plant diet. The bladder stores these salts until the tortoise finds fresh drinking water. To regulate the amount of salt in their bodies, sea turtles and the brackish-living diamondback terrapin secrete excess salt in a thick sticky substance from their tear glands. Because of this, sea turtles may appear to be "crying" when on land.

Thermoregulation

Turtles, like other reptiles, have a limited ability to regulate their body temperature. This ability varies between species, and with body size. Small pond turtles regulate their temperature by crawling out of the water and basking in the sun, while small terrestrial turtles move between sunny and shady places to adjust their temperature. Large species, both terrestrial and marine, have sufficient mass to give them substantial thermal inertia, meaning that they heat up or cool down over many hours. The Aldabra giant tortoise weighs up to some 60 kg and is able to allow its temperature to rise to some 33 C on a hot day, and to fall naturally to around 29 C by night. Some giant tortoises seek out shade to avoid overheating on sunny days. On Grand Terre Island, food is scarce inland, shade is scarce near the coast, and the tortoises compete for space under the few trees on hot days. Large males may push smaller females out of the shade, and some then overheat and die.

Adult sea turtles, too, have large enough bodies that they can to some extent control their temperature. The largest turtle, the leatherback, can swim in the waters off Nova Scotia, which may be as cold as 8 C, while their body temperature has been measured at up to 12 C-change warmer than the surrounding water. To help keep their temperature up, they have a system of countercurrent heat exchange in the blood vessels between their body core and the skin of their flippers. The vessels supplying the head are insulated by fat around the neck.

Diet and feeding

Most turtle species are opportunistic omnivores; land-dwelling species are more herbivorous and aquatic ones more carnivorous. Generally lacking speed and agility, most turtles feed either on plant material or on animals with limited movements like mollusks, worms, and insect larvae. Some species, such as the African helmeted turtle and snapping turtles, eat fish, amphibians, reptiles (including other turtles), birds, and mammals. They may take them by ambush but also scavenge. The alligator snapping turtle has a worm-like appendage on its tongue that it uses to lure fish into its mouth. Tortoises are the most herbivorous group, consuming grasses, leaves, and fruits. Many turtle species, including tortoises, supplement their diet with eggshells, animal bones, hair, and droppings for extra nutrients.

Turtles generally eat their food in a straightforward way, though some species have special feeding techniques. The yellow-spotted river turtle and the painted turtle may filter feed by skimming the water surface with their mouth and throat open to collect particles of food. When the mouth closes, the throat constricts and water is pushed out through the nostrils and the gap in between the jaws. Some species employ a "gape-and-suck method" where the turtle opens its jaws and expands its throat widely, sucking the prey in.

The diet of an individual within a species may change with age, sex, and season, and may also differ between populations. In many species, juveniles are generally carnivorous but become more herbivorous as adults. With Barbour's map turtle, the larger female mainly eats mollusks while the male usually eats arthropods. Blanding's turtle may feed mainly on snails or crayfish depending on the population. The European pond turtle has been recorded as being mostly carnivorous much of the year but switching to water lilies during the summer. Some species have developed specialized diets such as the hawksbill, which eats sponges, the leatherback, which feeds on jellyfish, and the Mekong snail-eating turtle.

Communication and intelligence

While popularly thought of as mute, turtles make various sounds to communicate. One study which recorded 53 species found that all of them vocalized. Tortoises may bellow when courting and mating. Various species of both freshwater and sea turtles emit short, low-frequency calls from the time they are in the egg to when they are adults. These vocalizations may serve to create group cohesion when migrating. The oblong turtle has a particularly large vocal range; producing sounds described as clacks, clicks, squawks, hoots, various kinds of chirps, wails, hooos, grunts, growls, blow bursts, howls, and drum rolls.

Play behavior has been documented in some turtle species. In the laboratory, Florida red-bellied cooters can learn novel tasks and have demonstrated a long-term memory of at least 7.5 months. Similarly, giant tortoises can learn and remember tasks, and master lessons much faster when trained in groups. Tortoises appear to be able to retain operant conditioning nine years after their initial training. Studies have shown that turtles can navigate the environment using landmarks and a map-like system resulting in accurate direct routes towards a goal. Navigation in turtles have been correlated to high cognition function in the medial cortex region of the brain.

Defense
When sensing danger, a turtle may flee, freeze or withdraw into its shell. Freshwater turtles flee into the water, though the Sonora mud turtle may take refuge on land as the shallow temporary ponds they inhabit make them vulnerable. When startled, a softshell turtle may dive underwater and bury itself under the sea floor. If a predator persists, the turtle may bite or discharge from its cloaca. Several species produce foul-smelling chemicals from musk glands. Other tactics include threat displays and Bell's hinge-back tortoise can play dead. When attacked, big-headed turtle hatchlings squeal, possibly startling the predator.

Migration
Turtles are the only reptiles that migrate long distances, more specifically the marine species that can travel up to thousands of kilometers. Some non-marine turtles, such as the species of Geochelone (terrestrial), Chelydra (freshwater), and Malaclemys (estuarine), migrate seasonally over much shorter distances, up to around 27 km, to lay eggs. Such short migrations are comparable to those of some lizards, snakes, and crocodilians. Sea turtles nest in a specific area, such as a beach, leaving the eggs to hatch unattended. The young turtles leave that area, migrating long distances in the years or decades in which they grow to maturity, and then return seemingly to the same area every few years to mate and lay eggs, though the precision varies between species and populations. This "natal homing" has appeared remarkable to biologists, though there is now plentiful evidence for it, including from genetics.

How sea turtles navigate to their breeding beaches remains unknown. One possibility is imprinting as in salmon, where the young learn the chemical signature, effectively the scent, of their home waters before leaving, and remember that when the time comes for them to return as adults. Another possible cue is the orientation of the Earth's magnetic field at the natal beach. There is experimental evidence that turtles have an effective magnetic sense, and that they use this in navigation. Proof that homing occurs is derived from genetic analysis of populations of loggerheads, hawksbills, leatherbacks, and olive ridleys by nesting place. For each of these species, the populations in different places have their own mitochondrial DNA genetic signatures that persist over the years. This shows that the populations are distinct and that homing must be occurring reliably.

Reproduction and life cycle
Turtles have a wide variety of mating behaviors but do not form pair-bonds or social groups. In green sea turtles, females generally outnumber males. In terrestrial species, males are often larger than females and fighting between males establishes a dominance hierarchy for access to mates. For most semi-aquatic and bottom-walking aquatic species, combat occurs less often. Males of these species instead may use their size advantage to mate forcibly. In fully aquatic species, males are often smaller than females and rely on courtship displays to gain mating access to females.

Courtship and mounting
Courtship varies between species, and with habitat. It is often complex in aquatic species, both marine and freshwater, but simpler in the semi-aquatic mud turtles and snapping turtles. A male tortoise bobs his head, then subdues the female by biting and butting her before mounting. The male scorpion mud turtle approaches the female from the rear, and often resorts to aggressive methods such as biting the female's tail or hind limbs, followed by a mounting.

Female choice is important in some species, and female green sea turtles are not always receptive. As such, they have evolved behaviors to avoid the male's attempts at copulation, such as swimming away, confronting the male followed by biting or taking up a refusal position with her body vertical, her limbs widely outspread, and her plastron facing the male. If the water is too shallow for the refusal position, the females resort to beaching themselves, as the males do not follow them ashore.

All turtles fertilize internally; mounting and copulation can be difficult. In many species, males have a concave plastron that interlocks with the female's carapace. In species like the Russian tortoise, the male has a lighter shell and longer legs. The high, rounded shape of box turtles are particular obstacles for mounting. The male eastern box turtle leans backward and hooks onto the back of the female's plastron. Aquatic turtles mount in water, and female sea turtles support the mounting male while swimming and diving. During copulation, the male turtle aligns his tail with the female's so he can insert his penis into her cloaca. Some female turtles can store sperm from multiple males and their egg clutches can have multiple sires.

Eggs and hatchlings

Turtles, including sea turtles, lay their eggs on land, although some lay eggs near water that rises and falls in level, submerging the eggs. While most species build nests and lay eggs where they forage, some travel miles. The common snapping turtle walks 5 km on land, while sea turtles travel even further; the leatherback swims some 12000 km to its nesting beaches. Most turtles create a nest for their eggs. Females usually dig a flask-like chamber in the substrate. Other species lay their eggs in vegetation or crevices. Females choose nesting locations based on environmental factors such as temperature and humidity, which are important for developing embryos. Depending on the species, the number of eggs laid varies from one to over 100. Larger females can lay eggs that are greater in number or bigger in size. Compared to freshwater turtles, tortoises deposit fewer but larger eggs. Females can lay multiple clutches throughout a season, particularly in species that experience unpredictable monsoons. Most mother turtles do no more in the way of parental care than covering their eggs and immediately leaving, though some species guard their nests for days or weeks. Eggs vary between rounded, oval, elongated, and between hard- and soft-shelled. Most species have their sex determined by temperature. In some species, higher temperatures produce females and lower ones produce males, while in others, milder temperatures produce males and both hot and cold extremes produce females. There is experimental evidence that the embryos of Mauremys reevesii can move around inside their eggs to select the best temperature for development, thus influencing their sexual destiny. In other species, sex is determined genetically. The length of incubation for turtle eggs varies from two to three months for temperate species, and four months to over a year for tropical species. Species that live in warm temperate climates can delay their development.

Hatching young turtles break out of the shell using an egg tooth, a sharp projection that exists temporarily on their upper beak. Hatchlings dig themselves out of the nest and find safety in vegetation or water. Some species stay in the nest for longer, be it for overwintering or to wait for the rain to loosen the soil for them to dig out. Young turtles are highly vulnerable to predators, both in the egg and as hatchlings. Mortality is high during this period but significantly decreases when they reach adulthood. Most species grow quickly during their early years and slow down when they are mature.

Lifespan
Turtles can live long lives. The oldest living turtle and land animal is said to be a Seychelles giant tortoise named Jonathan, who turned 187 in 2019. A Galápagos tortoise named Harriet was collected by Charles Darwin in 1835; it died in 2006, having lived for at least 176 years. Most wild turtles do not reach that age. Turtles keep growing new scutes under the previous scutes every year, allowing researchers to estimate how long they have lived. They also age slowly. The survival rate for adult turtles can reach 99% per year.

Fossil history

Zoologists have sought to explain the evolutionary origin of the turtles, and in particular of their unique shells. In 1914, Jan Versluys proposed that bony plates in the dermis, called osteoderms, fused to the ribs beneath them, later called the "Polka Dot Ancestor" by Olivier Rieppel. The theory accounted for the evolution of fossil pareiasaurs from Bradysaurus to Anthodon, but not for how the ribs could have become attached to the bony dermal plates.

More recent discoveries have painted a different scenario for the evolution of the turtle's shell. The stem-turtles Eunotosaurus of the Middle Permian, Pappochelys of the Middle Triassic, and Eorhynchochelys of the Late Triassic lacked carapaces and plastrons but had shortened torsos, expanded ribs, and lengthened dorsal vertebrae. Also in the Late Triassic, Odontochelys had a partial shell consisting of a complete bony plastron and an incomplete carapace. The development of a shell reached completion with the Late Triassic Proganochelys, with its fully developed carapace and plastron. Adaptations that led to the evolution of the shell may have originally been for digging and a fossorial lifestyle.

The oldest known members of the Pleurodira lineage are the Platychelyidae, from the Late Jurassic. The oldest known unambiguous cryptodire is Sinaspideretes, a close relative of softshell turtles, from the Late Jurassic of China. During the Late Cretaceous and Cenozoic, members of the pleurodire families Bothremydidae and Podocnemididae became widely distributed in the Northern Hemisphere due to their coastal habits. The oldest known soft-shelled turtles and sea turtles appeared during the Early Cretaceous. Tortoises originated in Asia during the Eocene. A late surviving group of stem-turtles, the Meiolaniidae, survived in Australasia into the Pleistocene and Holocene.

External relationships
The turtles' exact ancestry has been disputed. It was believed they were the only surviving branch of the ancient evolutionary grade Anapsida, which includes groups such as procolophonids and pareiasaurs. All anapsid skulls lack a temporal opening while all other living amniotes have temporal openings. It was later suggested that the anapsid-like turtle skulls may be due to backward evolution rather than to anapsid descent. Fossil evidence has shown that early stem-turtles possessed small temporal openings.

Some early morphological phylogenetic studies have placed turtles closer to Lepidosauria (tuataras, lizards, and snakes) than to Archosauria (crocodilians and birds). By contrast, several molecular studies place turtles either within Archosauria, or, more commonly, as a sister group to extant archosaurs,  though an analysis conducted by Tyler Lyson and colleagues (2012) recovered turtles as the sister group of lepidosaurs instead. Ylenia Chiari and colleagues (2012) analyzed 248 nuclear genes from 16 vertebrates and suggested that turtles share a more recent common ancestor with birds and crocodilians. The date of separation of turtles and birds and crocodilians was estimated to be during the Permian. Through genomic-scale phylogenetic study of ultra-conserved elements (UCEs) to clarify the placement of turtles within reptiles, Nicholas Crawford and colleagues (2012) similarly found that turtles are closer to birds and crocodilians.

Using the draft (unfinished) genome sequences of the green sea turtle and the Chinese softshell turtle, Zhuo Wang and colleagues (2013) concluded that turtles are likely a sister group of crocodilians and birds. The external phylogeny of the turtles is shown in the cladogram below.

Internal relationships
Modern turtles and their extinct relatives with a complete shell are classified within the clade Testudinata. The most recent common ancestor of living turtles, corresponding to the split between Pleurodira (side-necked species) and Cryptodira (hidden necked species), is estimated to have occurred around during the Late Triassic. Robert Thompson and colleagues (2021) comment that living turtles have low diversity, relative to how long they existed. Diversity has been stable, according to their analysis, except for a single rapid increase around the Eocene-Oligocene boundary some 30 million years ago, and a large regional extinction at roughly the same time. They suggest that global climate change caused both events, as the cooling and drying caused the land to become arid and turtles to become extinct there, while new continental margins opened up by the climate change provided habitats for other species to evolve.

The cladogram, from Nicholas Crawford and colleagues 2015, shows the internal phylogeny of the Testudines down to the level of families. The analysis by Thompson and colleagues in 2021 supports the same structure down to the family level.

Differences between the two suborders
Turtles are divided into two living suborders: Cryptodira and Pleurodira. The two groups differ in the way the neck is retracted for protection. Pleurodirans retract their neck to the side and in front of the shoulder girdles, whereas cryptodirans retract their neck backward into their shell. These motions are enabled by the morphology and arrangement of neck vertebrae. Sea turtles (which belong to Cryptodira) have mostly lost the ability to retract their heads.

The adductor muscles in the lower jaw create a pulley-like system in both subgroups. However, the bones that the muscles articulate with differ. In Pleurodira, the pulley is formed with the pterygoid bones of the palate, but in Cryptodira the pulley is formed with the otic capsule. Both systems help to vertically redirect the adductor muscles and maintain a powerful bite.

A further difference between the suborders is the attachment of the pelvis. In Cryptodira, the pelvis is free, linked to the shell only by ligaments. In Pleurodira, the pelvis is sutured, joined with bony connections, to the carapace and to the plastron, creating a pair of large columns of bone at the back end of the turtle, linking the two parts of the shell.

Distribution and habitat
Turtles are widely distributed across the world's continents, oceans, and islands with terrestrial, fully aquatic, and semi-aquatic species. Sea turtles are mainly tropical and subtropical, but leatherbacks can be found in colder areas of the Atlantic and Pacific. Living Pleurodira all live in freshwater and are found only in the Southern Hemisphere. The Cryptodira include terrestrial, freshwater, and marine species, and these range more widely. The world regions richest in non-marine turtle species are the Amazon basin, the Gulf of Mexico drainages of the United States, and parts of South and Southeast Asia.

For turtles in colder climates, their distribution is limited by constraints on reproduction, which is reduced by long hibernations. North American species barely range above the southern Canadian border. Some turtles are found at high altitudes, for example, the species Terrapene ornata occurs up to 2000 m in New Mexico. Conversely, the leatherback sea turtle can dive over 1200 m. Species of the genus Gopherus can tolerate both below freezing and over 40 C in body temperature, though they are most active at 26 –.

Conservation

Among vertebrate orders, turtles are second only to primates in the percentage of threatened species. 360 modern species have existed since 1500 AD. Of these, 51–56% are considered threatened and 60% considered threatened or extinct. Turtles face many threats, including habitat destruction, harvesting for consumption, the pet trade, light pollution, and climate change. Asian species have a particularly high extinction risk, primarily due to their long-term unsustainable exploitation for food and medicine, and about 83% of Asia's non-marine turtle species are considered threatened. As of 2021, turtle extinction is progressing much faster than during the Cretaceous-Tertiary extinction. At this rate, all turtles could be extinct in a few centuries.

Turtle hatcheries can be set up when protection against flooding, erosion, predation, or heavy poaching is required. Chinese markets have sought to satisfy an increasing demand for turtle meat with farmed turtles. In 2007 it was estimated that over a thousand turtle farms operated in China. All the same, wild turtles continue to be caught and sent to market in large numbers, resulting in what conservationists have called "the Asian turtle crisis". In the words of the biologist George Amato, the hunting of turtles "vacuumed up entire species from areas in Southeast Asia", even as biologists still did not know how many species lived in the region. In 2000, all the Asian box turtles were placed on the CITES list of endangered species.

Harvesting wild turtles is legal in some American states, and there has been a growing demand for American turtles in China. The Florida Fish and Wildlife Conservation Commission estimated in 2008 that around 3,000 pounds of softshell turtles were exported weekly via Tampa International Airport. However, the great majority of turtles exported from the US between 2002 and 2005 were farmed.

Large numbers of sea turtles are accidentally killed in longlines, gillnets, and trawling nets as bycatch. A 2010 study suggested that over 8 million had been killed between 1990 and 2008; the Eastern Pacific and the Mediterranean were identified as among the areas worst affected. Since the 1980s, the United States has required all shrimp trawlers to fit their nets with turtle excluder devices that prevent turtles from being entangled in the net and drowning. More locally, other human activities are affecting marine turtles. In Australia, Queensland's shark culling program, which uses shark nets and drum lines, has killed over 5,000 turtles as bycatch between 1962 and 2015; including 719 loggerhead turtles and 33 hawksbill sea turtles, which are listed as critically endangered.

Native turtle populations can also be threatened by invasive ones. The central North American red-eared slider turtle has been listed among the "world's worst invasive species", pet turtle having been released globally. They appear to compete with native turtle species in eastern and western North America, Europe, and Japan.

On space flights
Two tortoises were on the Soviet Union's September 1968 Zond 5 circumlunar flight, making them the first earthly living things to travel to the vicinity of the Moon. Turtles were also on the Zond 6 (1968) and the Zond 7 (1969) circumlunar flights.

In culture
Turtles have featured in human cultures across the world since ancient times. They are generally viewed positively despite not being "cuddly" or flashy; their association with the ancient times and old age have contributed to their endearing image.

In Hindu mythology, the World Turtle, named Kurma or Kacchapa, supports four elephants on his back; they, in turn, carry the weight of the whole world on their backs. The turtle is one of the ten avatars or incarnations of the god Vishnu. The yoga pose Kurmasana is named for the avatar. World Turtles are found in Native American cultures including the Algonquian, Iroquois, and Lenape. They tell many versions of the creation story of Turtle Island. One version has Muskrat pile up earth on Turtle's back, creating the continent of North America. An Iroquois version has the pregnant Sky Woman fall through a hole in the sky between a tree's roots, where she is caught by birds who land her safely on Turtle's back; the Earth grows around her. The turtle here is altruistic, but the world is a heavy burden, and the turtle sometimes shakes itself to relieve the load, causing earthquakes.

A turtle was the symbol of the Ancient Mesopotamian god Enki from the 3rd millennium BCE onward. An ancient Greek origin myth told that only the tortoise refused the invitation of the gods Zeus and Hera to their wedding, as it preferred to stay at home. Zeus then ordered it to carry its house with it, ever after. Another of their gods, Hermes, invented a seven-stringed lyre made with the shell of a tortoise. In the Shang dynasty Chinese practice of plastromancy, dating back to 1200 BCE, oracles were obtained by inscribing questions on turtle plastrons using the oldest known form of Chinese characters, burning the plastron, and interpreting the resulting cracks. Later, the turtle was one of the four sacred animals in Confucianism, while in the Han period, steles were mounted on top of stone turtles, later linked with Bixi, the turtle-shelled son of the Dragon King. Marine turtles feature significantly in Australian Aboriginal art. The army of Ancient Rome used the testudo ("tortoise") formation where soldiers would form a shield wall for protection.

In Aesop's Fables, "The Tortoise and the Hare" tells how an unequal race may be won by the slower partner. Lewis Carroll's 1865 Alice's Adventures in Wonderland features a Mock Turtle, named for a soup meant to imitate the expensive soup made from real turtle meat. In 1896, the French playwright Léon Gandillot wrote a comedy in three acts named La Tortue that was "a Parisian sensation" in its run in France, and came to the Manhattan Theatre, Broadway, New York, in 1898 as The Turtle. A "cosmic turtle" and the island motif reappear in Gary Snyder's 1974 novel Turtle Island, and again in Terry Pratchett's Discworld series as Great A'Tuin, starting with the 1983 novel The Colour of Magic. It is supposedly of the species Chelys galactica, the galactic turtle, complete with four elephants on its back to support Discworld. A giant fire-breathing turtle called Gamera is the star of a series of Japanese monster movies in the kaiju genre and has had twelve films from 1965 to 2006. Turtles have been featured in comic books and animations such as the 1984 Teenage Mutant Ninja Turtles.

As pets
Some turtles, particularly small terrestrial and freshwater species, are kept as pets. The demand for pet turtles increased in the 1950s, with the US being the main supplier, particularly of farm-bred red-eared sliders. The popularity for exotic pets has led to an increase in illegal wildlife trafficking. Around 21% of the value of live animal trade is in reptiles, and turtles are among the more popularly traded species. Poor husbandry of tortoises can cause chronic rhinitis (nasal swelling), overgrown beaks, hyperparathyroidism (which softens their skeleton), constipation, various reproductive problems, and injuries from dogs. In the early 20th century, people in the United States have organized and gambled on turtle races.

As food and other uses
The flesh of captured wild turtles continues to be eaten in Asian cultures, while turtle soup was once a popular dish in English cuisine. Gopher tortoise stew has been popular with some groups in Florida. The supposed aphrodisiac or medicinal properties of turtle eggs created a large trade for them in Southeast Asia. Hard-shell turtle plastrons and soft-shell carapaces are widely used in traditional Chinese medicine; Taiwan imported nearly 200 metric tons of hard-shells from its neighbors yearly from 1999 to 2008. A popular medicinal preparation based on herbs and turtle shells is guilinggao jelly. The substance tortoiseshell, usually from the hawksbill turtle, has been used for centuries to make jewelry, tools, and ornaments around the Western Pacific. Hawksbills have accordingly been hunted for their shells. The trading of tortoiseshell was internationally banned in 1977 by CITES. Some cultures have used turtle shells to make music: Native American shamans made them into ceremonial rattles, while Aztecs, Mayas, and Mixtecs made ayotl drums.

title: Turtle


text:
Éraic

Éraic (or eric) was the Irish equivalent of the Welsh galanas and the Anglo-Saxon and Scandinavian weregild, a form of tribute paid in reparation for murder or other major crimes. The term survived into the sixteenth century as eiric, by then relating only to compensation for the killing of an Irishman. In the case of homicide, if the attacker fled, the fine had to be paid by the tribe to which he belonged and the criminal's soul.

In Irish mythology the éraic takes an important place. In the Oidheadh Chloinne Tuireann, the children of Tuireann owed an éraic to Lugh. Lug set them a series of seemingly impossible quests as recompense. They achieved them all, but were fatally wounded in completing the last one.

title: Éraic