Clément Zanolli
email: clement.zanolli@gmail.com

Florian Bouchet

Josep Fortuny

Federico Bernardini

Claudio Tuniz

David M Alba
email: david.alba@icp.cat

A reassessment of the distinctiveness of dryopithecine genera from the Iberian Miocene based on enamel-dentine junction geometric morphometric analyses

Keywords: Anoiapithecus, Dryopithecus, Hispanopithecus, Pierolapithecus, Hominoidea, Spain

établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction

Over the past two decades, discoveries in various Middle to Late Miocene localities of the Vallès-Penedès Basin (NE Iberian Peninsula;Casanovas-Vilar et al., 2016a) have revealed a previously unsuspected (e.g., see [START_REF] Andrews | Distribution and biochronology of European and Southwest Asian Miocene catarrhines[END_REF] high diversity of primates [START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF][START_REF] Marigó | The primate fossil record in the Iberian Peninsula[END_REF][START_REF] Alba | Ten years in the dump: An updated review of the Miocene primate-bearing localities from Abocador de Can Mata (NE Iberian Peninsula)[END_REF][START_REF] Alba | A revised (earliest Vallesian) age for the hominoid-bearing locality of Can Mata 1 based on new magnetostratigraphic and biostratigraphic data from Abocador de Can Mata (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF], including multiple small-bodied catarrhines [START_REF] Moyà-Solà | Egarapithecus narcisoi, a new genus of Pliopithecidae (Primates, Catarrhini) From the Late Miocene of Spain[END_REF]Alba et al., 2010aAlba et al., , 2012a[START_REF] Alba | Miocene small-bodied ape from Eurasia sheds light on hominoid evolution[END_REF]Alba and Moyà-Solà, 2012a) as well as fossil great apes [START_REF] Moyà-Solà | Pierolapithecus catalaunicus, a new Middle Miocene great ape from Spain[END_REF], 2009a, 2009b;[START_REF] Alba | A partial hominoid humerus from the middle Miocene of Castell de Barberà (Vallès-Penedès Basin, Catalonia, Spain)[END_REF]Alba et al., , 2012a;;Alba and Moyà-Solà, 2012b). The presence of fossil catarrhines in the NE Peninsula has been related to the moister and more forested environments than elsewhere in Iberia during the late Aragonian and Vallesian, being more similar to those from France and Central Europe (ca. 12.6-8.9 Ma; [START_REF] Casanovas-Vilar | Biochronological, taphonomical and paleoenvironmental background of the fossil great ape Pierolapithecus catalaunicus (Primates, Hominidae)[END_REF], 2016a, 2016b;[START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF][START_REF] Marmi | The paleoenvironment of Hispanopithecus laietanus as revealed by paleobotanical evidence from the Late Miocene of Can Llobateres 1 (Catalonia, Spain)[END_REF][START_REF] Alba | Can Pallars i Llobateres: A new hominoidbearing locality from the late Miocene of the Vallès-Penedès Basin (NE Iberian Peninsula)[END_REF]. In turn, the recognition of a greater diversity than expected mainly stems from the large sampling effort devoted during the last couple decades to Middle Miocene sites [START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF][START_REF] Alba | Ten years in the dump: An updated review of the Miocene primate-bearing localities from Abocador de Can Mata (NE Iberian Peninsula)[END_REF][START_REF] Alba | A revised (earliest Vallesian) age for the hominoid-bearing locality of Can Mata 1 based on new magnetostratigraphic and biostratigraphic data from Abocador de Can Mata (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF], which led to the realization that different dryopithecine genera were recorded in the Middle and Late Miocene of Europe (Moyà-Solà et al., 2009a;[START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF], and has been recently substantiated by recent discoveries elsewhere in Europe [START_REF] Böhme | A new Miocene ape and locomotion in the ancestor of great apes and humans[END_REF].

While there is consensus that Late Miocene dryopithecines belong to different genera than Dryopithecus (Moyà-Solà et al., 2009a;[START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF], the distinctiveness of the Middle Miocene genera Pierolapithecus and Anoiapithecus from Dryopithecus has been challenged by Begun and coauthors [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF], who, based on various similarities (reduced maxillary sinus and resemblances in overall dental morphology), concluded that Pierolapithecus and Anoiapithecus are likely junior subjective synonyms of Dryopithecus (i.e., genus names subsequently established based on different type specimens that, in the authors' opinion, do not warrant a distinction at the genus rank). The distinction of these three genera is mostly based on cranial differences (such as the presence of a frontal sinus, the position of the zygomatic root, or the degree of prognathism) coupled with more subtle dental differences [START_REF] Moyà-Solà | Pierolapithecus catalaunicus, a new Middle Miocene great ape from Spain[END_REF], 2009a, 2009b;[START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF][START_REF] De Los Ríos | The nasal and paranasal architecture of the Middle Miocene ape Pierolapithecus catalaunicus (Primates: Hominidae): Phylogenetic implications[END_REF][START_REF] Fleagle | Primate Adaptation and Evolution, 3rd Ed[END_REF]Alba et al., 2013Alba et al., , 2020;;[START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. In turn, the postcranial evidence available indicates multiple differences between Pierolapithecus and the Late Miocene Hispanopithecus, but the more scanty evidence available for Dryopithecus and the absence of postcranial remains for Anoiapithecus do not enable reliable conclusions for these Middle Miocene dryopithecines [START_REF] Moyà-Solà | Pierolapithecus catalaunicus, a new Middle Miocene great ape from Spain[END_REF], 2009a;[START_REF] Almécija | Orang-like manual adaptations in the fossil hominoid Hispanopithecus laietanus: first steps towards great ape suspensory behaviours[END_REF][START_REF] Almécija | Pierolapithecus and the functional morphology of Miocene ape hand phalanges: paleobiological and evolutionary implications[END_REF]Alba et al. 2010b[START_REF] Alba | A partial hominoid humerus from the middle Miocene of Castell de Barberà (Vallès-Penedès Basin, Catalonia, Spain)[END_REF]Alba et al. , 2012b;;[START_REF] Pina | Brief Communication: Paleobiological inferences on the locomotor repertoire of extinct hominoids based on femoral neck cortical thickness: the fossil great ape Hispanopithecus laietanus as a test-case study[END_REF][START_REF] Pina | Femoral neck cortical bone distribution of dryopithecin apes and the evolution of hominid locomotion[END_REF].

Previous analyses of the internal dental structure showed that Dryopithecus has proportionally thin enamel, as in the African great apes, while Pierolapithecus and Anoiapithecus display moderately thick enamel, similar to Pongo (Alba et al., 2010b(Alba et al., , 2012a[START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. In addition, some distinctive features were described on the outer enamel surface (OES) between Pierolapithecus and Dryopithecus (including thick and inflated crests, secondary enamel folds, and cusp base morphology; [START_REF] Alba | New dental remains of Anoiapithecus and the first appearance datum of hominoids in the Iberian Peninsula[END_REF][START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF][START_REF] De Los Ríos | Taxonomic attribution of the La Grive hominoid teeth[END_REF] that are not visible at the level of the enamel-dentine junction (EDJ), probably due to differences in enamel thickness between the two genera [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. The external occlusal morphology and enamel thickness stem from the evolutionary interplay between functional/adaptive factors and strict control mechanisms of the morphogenetic program, and they respond relatively quickly in evolutionary time to dietary/ecological changes (reviewed in [START_REF] Zanolli | Is the deciduous/permanent molar enamel thickness ratio a taxonspecific indicator in extant and extinct hominids?[END_REF]. Conversely, the EDJ is the developmental precursor of crown shape and is more conservative than the enamel in evolutionary terms (i.e., reflecting macrevolutionary vs. microevolutionary changes, respectively; Korehof, 1961;[START_REF] Olejniczak | Quantification of dentine shape in anthropoid primates[END_REF][START_REF] Skinner | Dental trait expression at the enamel-dentine junction of lower molars in extant and fossil hominoids[END_REF], carrying a marked phylogenetic signal in its shape (Zanolli et al., 2022b). The EDJ is recognized as a reliable taxonomic proxy to distinguish extinct and extant hominid taxa (e.g., [START_REF] Skinner | Dental trait expression at the enamel-dentine junction of lower molars in extant and fossil hominoids[END_REF][START_REF] Skinner | Discrimination of extant Pan species and subspecies using the enamel-dentine junction morphology of lower molars[END_REF][START_REF] Macchiarelli | From outer to inner structural morphology in dental anthropology. The integration of the third dimension in the visualization and quantitative analysis of fossil remains[END_REF][START_REF] Fornai | Variability of Australopithecus second maxillary molars from Sterkfontein Member 4[END_REF][START_REF] Zanolli | Brief Communication: The Early Pleistocene deciduous hominid molar FS-72 from the Sangiran Dome of Java, Indonesia: A taxonomic reappraisal based on its comparative endostructural characterization[END_REF][START_REF] Zanolli | Evidence for increased hominid diversity in the Early-Middle Pleistocene of Indonesia[END_REF]Zanolli et al., , 2022a;;[START_REF] Pan | Further morphological evidence on South African earliest Homo lower postcanine dentition: enamel thickness and enamel-dentine junction[END_REF][START_REF] Pan | Hominin diversity in East Asia during the Middle Pleistocene: A premolar endostructural perspective[END_REF]. A number of traits were identified on the EDJ of Pierolapithecus maxillary molars that differ from Dryopithecus (deeper trigon basin, higher and straighter crista obliqua, lingual dentine horns mesiodistally aligned, less cervical buccolingual waisting, less developed lingual cingulum; Fig. 1A) and from Anoiapithecus (shallower and less restricted mesial fovea, M 1 and M 2 hypocone dentine horn less lingually situated relative to that of the protocone, markedly less buccolingually waisted cervix, and more weakly developed lingual cingulum; Fig. 1A; [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF].

The lower dentition of Pierolapithecus is unknown and most of the lower molars of Anoiapithecus are either not well preserved or worn, which complicates the diagnosis of isolated teeth or dentognathic fragments found in the Middle Miocene sites of the Vallès-Penedès Basin.

In particular, two specimens are currently attributed to 'Sivapithecus' occidentalis species inquirenda [START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]: IPS1826+IPS1827 (holotype), including the M2 and M3 of a single individual; and IPS41734, a mandibular fragment with M2. The taxonomic allocation of the holotype specimen has varied among authors throughout the years, but most recently [START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF] considered it a species inquirenda because the lack of suitable material to compare it with other taxa makes it impossible to determine its taxonomic attribution with certainty (i.e., it is "a species of doubtful identity needing further investigation;" ICZN, 1999: Glossary). The three molars of 'S.' occidentalis exhibit thick enamel, excluding the possibility that they belong to Dryopithecus [START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. They also show thinner enamel than the two species of Hispanopithecus, as well as a combination of different morphological characteristics at the EDJ (including more centrally tilted metaconid dentine horns, with a well-developed metaconulid dentine horn; Fig. 1B). 'Sivapithecus' occidentalis is a senior subjective synonym of either Pierolapithecus catalaunicus or Anoiapithecus brevirostris (i.e., 'S.' occidentalis was established, based on a different type specimen, before the other species, and it would thus take precedence if it was eventually considered that it is conspecific with either of them). This is indeed likely, given that the holotypes of these species come from the same area and a very restricted time span of less than 100 kyr [START_REF] Alba | A revised (earliest Vallesian) age for the hominoid-bearing locality of Can Mata 1 based on new magnetostratigraphic and biostratigraphic data from Abocador de Can Mata (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF], but currently available data from the occlusal surface are insufficient to reach a definitive conclusion in this regard [START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF].

To further investigate the taxonomic diversity of Iberian dryopithecines and to test whether the genera currently recognized (Pierolapithecus, Anoiapithecus, Dryopithecus, and Hispanopithecus) can be readily distinguished on dental grounds, we conducted diffeomorphic surface matching and three-dimensional (3D) geometric morphometrics of the EDJ shape. We also evaluated the degree of intra-and intergeneric variation of these dryopithecine genera in comparison with that of extant great ape genera.

Materials and methods

Dryopithecine specimens and extant comparative sample

The Miocene dryopithecine sample includes 45 molars from 25 specimens from the Vallès-Penedès and Seu d'Urgell basins (Catalonia, Spain), housed at the Institut Català de Paleontologia Miquel Crusafont. Details of the µCT scans, segmentation process, and description of the EDJ of these specimens are reported in [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. The surface models of the EDJ of these dryopithecine molars are available on MorphoSource (https://www.morphosource.org; the list of the digital object identifiers for each specimens can be found in Supplementary Online Material [SOM] Table S1). Four molars belonging to three specimens attributed to Dryopithecus fontani from Saint-Gaudens (type locality), in France, were used as reference material. The D. fontani specimens are curated at the Muséum de Bordeaux.

More information on the fossil samples is available in SOM Table S1. One specimen, IPS1816, was previously regarded as an M2, but based on root morphology as shown by the µCT scan (especially that of the mesially-located tooth that resembles more a P4 root; SOM Fig. S1), and in agreement with the general crown morphology, it is more likely to represent an M1.

The extant comparative sample includes 60 molars per genus (10 upper and 10 lower teeth per molar position and per genus) for Pan, Gorilla, and Pongo (SOM Table S2). For each molar position, because of the limited availability of extant comparative material, the antimeres of some specimens were sometimes used to reach 10 teeth/genus. It is also recommendable to include antimeres for the extant species because it cannot be excluded that some of the right and left isolated molars from the same position and fossil locality belong to a single individual. To represent as much as possible the extant intrageneric variation, specimens of both sexes, from various geographic areas, and of different species (with two species of Pan-Pan troglodytes and Pan paniscus-and two species of Pongo-Pongo pygmaeus and Pongo abelii) were included (SOM Table S2).

Geometric morphometric analyses of the enamel-dentine junction

We used a diffeomorphic surface matching (DSM) approach to analyze EDJ shape [START_REF] Durrleman | Comparison of the endocranial ontogenies between chimpanzees and bonobos via temporal regression and spatiotemporal registration[END_REF][START_REF] Durrleman | Morphometry of anatomical shape complexes with dense deformations and sparse parameters[END_REF]. Diffeomorphic surface matching analyses can capture the taxonomically relevant aspects of EDJ morphology [START_REF] Beaudet | Upper third molar internal structural organization and semicircular canal morphology in Plio-Pleistocene South African cercopithecoids[END_REF][START_REF] Zanolli | Inner tooth morphology of Homo erectus from Zhoukoudian. New evidence from an old collection housed at Uppsala University, Sweden[END_REF]Zanolli et al., , 2022a;;[START_REF] Braga | Efficacy of diffeomorphic surface matching and 3D geometric morphometrics for taxonomic discrimination of Early Pleistocene hominin mandibular molars[END_REF], including both prominent features (such as the dentine horns and marginal crests) and more subtle features (like the protostylid and occlusal basin morphology), and thus improves on traditional (semi)landmark-based geometric morphometric analyses [START_REF] Zanolli | Inner tooth morphology of Homo erectus from Zhoukoudian. New evidence from an old collection housed at Uppsala University, Sweden[END_REF][START_REF] Braga | Efficacy of diffeomorphic surface matching and 3D geometric morphometrics for taxonomic discrimination of Early Pleistocene hominin mandibular molars[END_REF][START_REF] Urciuoli | The evolution of the vestibular apparatus in apes and humans[END_REF]Urciuoli et al., , 2021a)). This landmark-free, meshbased approach relies on the construction of average surface models, and the difference between surfaces is interpreted as the amount of deformation needed to align them by using diffeomorphic shape matching [START_REF] Glaunès | Template estimation from unlabeled point set data and surfaces for computational anatomy[END_REF][START_REF] Durrleman | Morphometry of anatomical shape complexes with dense deformations and sparse parameters[END_REF]. The deformations between surfaces are mathematically modeled as smooth and invertible functions (i.e., diffeomorphisms).

From a set of surfaces, an atlas of surfaces is created. The method estimates an average object configuration or mean shape from a collection of object sets (here the EDJ surfaces) and computes the deformations from the mean shape to each specimen. In addition, a set of initial control points located near its most variable parts, and a set of momenta parameterizing the deformations of the mean shape to each specimen are estimated [START_REF] Durrleman | Comparison of the endocranial ontogenies between chimpanzees and bonobos via temporal regression and spatiotemporal registration[END_REF].

For each tooth position, the EDJ surfaces decimated to 50,000 polygons were manually oriented, then superimposed using the rigid and uniform scale option of the 'Align Surfaces' module in Avizo v. 7.0 (FEI Visualization Sciences Group, Hillsboro). This was done by minimizing the root mean square distance between the points of each specimen to corresponding points on the reference surface using an iterative closest-point algorithm. We used Deformetrica v. 4.3 software [START_REF] Bône | Deformetrica 4: An open-source software for statistical shape analysis[END_REF] to generate a global mean shape with a set of diffeomorphisms relating the global mean shape to each individual and the output (control points and deformation momenta) used to perform the statistical analyses to explore the EDJ shape variation and to classify the data. Deformations were computed at the IN2P3 Computing Center (Lyon, France).

The output data were imported into R v. 4.1.3 (R Core Team, 2022) with the package 'RToolsForDeformetrica' v. 0.1 [START_REF] Dumoncel | RToolsForDeformetrica. R package version 0[END_REF]. Using the packages 'ade4' v. 1.7-6 [START_REF] Dray | The ade4 package: Implementing the duality diagram for ecologists[END_REF][START_REF] Dray | The ade4 package: Implementing the duality diagram for ecologists[END_REF]'Morpho' v. 2.8 (Schlager, 2020) for R, we first computed principal component analyses (PCAs), followed by between-group PCAs (bgPCAs) based on the deformation moments and using the following three groups assigned with equal prior probabilities: Pan, Gorilla, and Pongo. The Iberian Miocene specimens were then projected a posteriori into the bgPCA morphospace. We followed the recommendations of [START_REF] Cardini | Cross-validated between group PCA scatterplots: A solution to spurious group separation?[END_REF] by computing cross-validated bgPCAs (cv-bgPCAs) to ensure that group discrimination is not spurious using the package 'Morpho'. We also performed cross-validated canonical variates analyses (CVAs) using the same groups as for the bgPCAs using the R package 'Morpho'. Since CVA computation requires the number of variables to be much smaller than the number of specimens, we computed the CVAs based on a subset of the first principal component (PC)

scores showing the highest degree of correct classification (screening the correct classification results and selecting the minimum number of PC scores enabling to reach the optimum of correct classification; [START_REF] Hastie | The Elements of Statistical Learning[END_REF]. Between three and six PC scores representing ca. 60 to 76% of the total variance were selected for CVA analyses. This choice of PC scores subset is a compromise between including a sufficient proportion of overall shape variation and limiting the number of variables to avoid unrealistic and unstable levels of discrimination [START_REF] Skinner | Discrimination of extant Pan species and subspecies using the enamel-dentine junction morphology of lower molars[END_REF]. We also assessed the structuration of data and results of the multivariate analyses to test that group separation is not spurious [START_REF] Cardini | Cross-validated between group PCA scatterplots: A solution to spurious group separation?[END_REF]. The amount of variance (r 2 ) explained by group differences in the raw shape data was estimated by computing a permutational multivariate analysis of variance (PERMANOVA; 1000 permutations) based on the Euclidean distance between the means and implementing a Holm correction using the R packages 'vegan' v. 2.5-7 [START_REF] Oksanen | vegan: Community ecology package. R package version 2[END_REF]'pairwiseAdonis' v. 0.3 (Martínez Arbizu, 2020).

We computed the Euclidian distances (EDs) between specimens for the bgPCA and CVA scores to assess intra-and intergeneric variation in the comparative sample (for an example with Procrustes distances, see [START_REF] Spoor | Reconstructed Homo habilis type OH 7 suggests deep-rooted species diversity in early Homo[END_REF]. Distances for bgPCA and CVA scores were computed between each specimen of the same genus (i.e., intrageneric variation) for both extant and extinct genera, and also between specimens of samples combining two or more different dryopithecine genera (i.e., intergeneric variation). To ensure that these analyses were not biased by the small sizes of the fossil samples we further performed permutation tests. For intrageneric variation analyses, fossil samples were restricted to the specimens available for each genus. For intergeneric variation analyses, fossil samples included specimens from two or more genera to test the hypotheses that Pierolapithecus and Anoiapithecus might be junior synonyms of Dryopithecus [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF] and that 'Sivapithecus' occidentalis species inquirenda [START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]) might be a senior synonym of P. catalaunicus or A. brevirostris. For each fossil sample, the ED based on the scores of the two first bgPCs (representing more than 90-95% of the variance) and CVs (representing 100% of the variance) was computed for each pair of specimens and the average ED was calculated. For each extant genus, we generated all the possible combinations (permutations) of specimens with the same sample size as the fossil sample of interest, and average ED for each set of permutations was calculated as explained above. Average ED for each fossil sample was then compared with the distribution of average EDs for the corresponding extant set of permutations. The probability of each fossil sample displaying a lower variation than each extant genus was computed by dividing the number of extant permutations with a higher or equal average ED than that of the fossil sample by the total number of extant permutations. The null hypothesis that a given fossil sample does not exceed the variation seen within an extant genus was rejected when the aforementioned probability (interpreted as a p-value) was lower than 5% (p < 0.05). For intergeneric comparisons (i.e., including specimens from multiple dryopithecine genera), rejecting the null hypothesis would support the existence of more than a single genus (unless more variable than extant ones), whereas failure to reject the null hypothesis would be compatible with a single genus (but would not reject the presence of multiple genera).

Results

Comparisons between bgPCA and cv-bgPCA plots show a similar degree of discrimination between Pan, Gorilla, and Pongo (Fig. 2; SOM Fig. S2). Results of the PERMANOVA based on the raw data confirm the high level of discrimination between the three groups for all tooth positions (SOM Table S3). Results of the CVA are similar to those of bgPCA (Figs. 2 and3). The EDJs of both maxillary and mandibular molars of each extant genus are equally correctly classified, but M1s and M2s show a greater taxonomic discriminatory power than M3s (SOM Tables S3 andS4). Correct classification for each group and overall classification resulting from the cv-bgPCA and CVA are reported in SOM Table S4. Collectively, bgPCA, cv-bgPCA, and and3). In particular, the M 2 s of Anoiapithecus and Pierolapithecus, as well as some M 2 s and M2s of Hispanopithecus, tend to be closer to the morphology of Pan than to that of the other extant great apes. This is supported by typicality probabilities, even if for a number of dryopithecine specimens, the highest value is lower than 0.05, indicating that they are outside the variation of the extant genera (Table 1). Despite the limited sample size of the Miocene hominids, the teeth belonging to the same genus tend to cluster together for most tooth positions (only for the M 3 , the range of Hispanothecus specimens is relatively large, similar to that of Pongo). While the distribution of the various Miocene specimens does not exceed that of the extant great apes for the first molars (comparable to the extent of variation of Pongo), second and third molars are more widely scattered than they are in the extant great ape genera.

When investigating the Euclidian distances between specimens, the intrageneric variation of extant apes is limited to a similar range for each extant great ape genus in both the bgPCA (Fig. 4) and CVA (Fig. 5). Gorilla and Pan are generally less variable in EDJ shape than Pongo.

Hispanopithecus M 3 and M2 EDJ vary the most among the fossil genera, but they are within a similar range to that of Pongo (Figs. 4C and5C, E), except in the M2 bgPCA morphospace,

where Hispanopithecus shows a higher degree of variation than each extant genus (Fig. 4E). For the M 2 position, Dryopithecus appears to differ more from both Anoiapithecus and Pierolapithecus than the two latter genera from one another (Figs. 4B and5B). Pierolapithecus M 3 EDJ differs from that of the other Miocene genera due to the highly mesiodistally compressed crown morphology [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]: Fig. 4C). 'Sivapithecus' occidentalis M2 and M3 EDJ differ more from Hispanopithecus than Dryopithecus.

Permutation tests based on the bgPCA and CVA scores confirm that the Miocene genera exhibit a degree of molar EDJ intrageneric variation that is generally not greater than that of extant great ape genera (Table 2). The only exceptions are the Hispanopithecus M 3 s (which vary more than those of Gorilla and Pan but not Pongo) and M2s (which show variation even exceeding the range of the three extant great ape genera (except Pongo based on the bgPCA results). By contrast, when the permutation tests are repeated by mixing teeth of different Middle Miocene taxa, the results are somewhat different, as in multiple instances their variation exceeds that of one or more extant great ape genera (Table 3). Fossil samples including Anoitapithecus, Dryopithecus, and Pierolapithecus are only available for the upper molars. The M 1 variation only surpasses that of Gorilla based on the bgPCA results, but M 3 variation exceeds that of both Gorilla and Pan, and M 2 variation exceeds that of all extant great ape genera. The results for the M 3 might be explained by a high degree of variation (as in Hispanopithecus, see above) but those for the M 2 support the presence of more than a single genus in the Middle Miocene sample.

When intergeneric variation is evaluated by mixing two extinct genera at a time (Table 3)

Discussion and conclusions

The taxonomic diversity of Iberian dryopithecines has been discussed frequently in the last decades, notably due to the increasing number of discoveries in the various localities of the Vallès-Penedès Basin (see review in [START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF]. There is a general consensus that the Middle Miocene genera Pierolapithecus, Anoiapithecus, and Dryopithecus differ from the Late Miocene Hispanopithecus and Rudapithecus (Moyà-Solà et al., 2009a;[START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF][START_REF] Almécija | Fossil apes and human evolution[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF][START_REF] Pugh | Phylogenetic analysis of Middle-Late Miocene apes[END_REF], being classified into two distinct tribes (Dryopithecini and Hispanopithecini, respectively; Alba, 2012). However, the distinctiveness of the former three genera, which are roughly coeval [START_REF] Casanovas-Vilar | Updated chronology for the Miocene hominoid radiation in Western Eurasia[END_REF][START_REF] Alba | Ten years in the dump: An updated review of the Miocene primate-bearing localities from Abocador de Can Mata (NE Iberian Peninsula)[END_REF], has been questioned on several occasions, often based on arguments involving dental morphology [START_REF] Begun | Fossil record of Miocene hominoids[END_REF][START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | Miocene hominids and the origins of the African apes and humans[END_REF][START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF]. For example, Pierolapithecus and Dryopithecus were described as sharing the large canines, short premolars, partial cingulum of the molars, and smaller M1 relative to M2, and Anoiapithecus was also regarded as sharing similar features [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF]. However, it is widely recognized that dryopithecines are dentally conservative and that the distinction among different genera is largely based on cranial and postcranial features (e.g., [START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF][START_REF] Almécija | Fossil apes and human evolution[END_REF], even though some dental differences have previously been noticed [START_REF] Alba | New dental remains of Anoiapithecus and the first appearance datum of hominoids in the Iberian Peninsula[END_REF][START_REF] De Los Ríos | Taxonomic attribution of the La Grive hominoid teeth[END_REF]. The overall degree of similarity within the Iberian dryopithecine genera is likely related to their short stratigraphic ranges. Specimens from Abocador de Can Mata span from ∼12.4-11.9

Ma [START_REF] Alba | Ten years in the dump: An updated review of the Miocene primate-bearing localities from Abocador de Can Mata (NE Iberian Peninsula)[END_REF][START_REF] Alba | A revised (earliest Vallesian) age for the hominoid-bearing locality of Can Mata 1 based on new magnetostratigraphic and biostratigraphic data from Abocador de Can Mata (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF], and the Hispanopithecus remains range between ∼10.5 and 9.5 Ma [START_REF] Alba | Can Pallars i Llobateres: A new hominoidbearing locality from the late Miocene of the Vallès-Penedès Basin (NE Iberian Peninsula)[END_REF]. These ranges are shorter than the molecular divergence dates of the extant species of Pan (~2 Myr; [START_REF] Prüfer | The bonobo genome compared with the chimpanzee and human genomes[END_REF], suggesting that temporal trends are unlikely to play a substantial role in inflating the variation of these previously recognized dryopithecine genera.

Previous analyses of the molar structural organization in the Iberian dryopithecines, including the detailed description of OES and EDJ morphology, as well as enamel thickness, supported the discrimination of Pierolapithecus, Anoiapithecus, Dryopithecus, and Hispanopithecus as distinct genera (Alba et al., 2010[START_REF] Alba | New dental remains of Anoiapithecus and the first appearance datum of hominoids in the Iberian Peninsula[END_REF][START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. Our results of the 3D geometric morphometric analyses of the EDJ are also in agreement with these former studies. As shown by the bgPCA, CVA, and Euclidian distance plots (Figs. 2345), the distribution of the Iberian dryopithecine genera exceeds the variation of each extant great ape genus, especially for the M2 and M3 positions, while M1s tend to be less variable (both in fossil and extant genera). This is confirmed by the permutation tests based on the upper molars, which reject the single-genus hypothesis and rather support the distinctiveness of Pierolapithecus and Anoiapithecus from one another as well as when compared with Dryopithecus.

It has been argued that the I 1 and M 3 of Pierolapithecus closely resemble those of Dryopithecus from La Grive [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF]. However, other authors have noted that the La Grive incisor differs in several respects from that of Pierolapithecus (and Hispanopithecus), whereas the upper molar (reinterpreted as a female M 1 ) more closely resembles Dryopithecus in crown height (Pérez de los Ríos et al., 2013). Regardless, the distance separating the EDJ of the only available M 3 of Pierolapithecus (IPS21350) from that of Dryopithecus (IPS35026) largely exceeds the intrageneric variation of the three extant great ape genera and, together with the permutation tests (Table 3), contradict the single-genus hypothesis.

In addition, the Dryopithecus M 2 displays a more buccolingually compressed central basin relative to crown base and more lingually-placed hypocone than that of Pierolapithecus (Fig. 1A; see also [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. Anoiapithecus and Dryopithecus M 2 s are also well distinguished and the distance between specimens exceeds the degree of variation displayed by the three extant great ape genera (Table 3), mostly due to the more asymmetric and higher EDJ in the former (Figs. 2345). These quantitative analyses support the distinction of these two taxa at genus rank and are in contradiction with the hypothesis that they are congeneric [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF]. It has also been suggested that Pierolapithecus and Anoiapithecus are dentally very similar and may belong to the same genus [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF]. The differences between the EDJ of the molars of these two genera are more or less marked depending on tooth position. For the M 2 , the EDJs of both taxa are morphologically quite similar, and the variation they express in the available sample does not exceed that of the extant great ape genera (Figs. 2345). However, for the M 1 and M 3 , these two dryopithecine genera are relatively distant in both the bgPCA and CVA (Figs. 2 and3). In fact, Pierolapithecus and Anoiapithecus M 3 specimens are more distant from each other than the specimens of each extant hominid genus are in the bgPCA space (Fig. 4C), and their variation is only included within the intrageneric range of Pongo in the CVA (Fig. 5C), as indicated by the permutation tests (Table 3). In terms of morphology, as previously described [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF], our results show that Pierolapithecus has more mesiodistal compressed EDJs (particularly for the M 3 ), with shorter and slightly more peripherally-placed dentine horns than Anoiapithecus. Even if the distinction between Pierolapithecus and Anoiapithecus is not as striking as that between Pierolapithecus and Dryopithecus, or between Anoiapithecus and Dryopithecus, the results of our geometric morphometric analyses of EDJ shape (in particular based on permutation tests for the M 3 ; Table 3) are consistent with the hypothesis that they represent different genera. These results are in further agreement with the previously described cranial differences between Anoiapithecus and Pierolapithecus, including prognathism (much more orthognathous facial profile in Anoiapithecus), presence vs. absence of a frontal sinus, thinner vs. thicker enamel, and more vs. less downward inclination of the zygomatic root (Moyà-Solà et al., 2009b;[START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF].

The taxonomic status of the M2s and M3 currently assigned to 'S.' occidentalis is also unclear as they have been suggested to belong to either P. catalaunicus or A. brevirostris (Alba et al., 2020). The permutation tests indicate that an attribution to Dryopithecus cannot be discounted (Table 3), but the lack of mandibular remains for Pierolapithecus and the fragmentary state of the Anoiapithecus specimen IPS43000 M2 (and absence of M3) preclude a more conclusive assessment. The EDJ shape analyses conducted here show that the three 'S.' occidentalis molars are closer to Dryopithecus than Hispanopithecus (IPS1826+1827 and IPS41734). These analyses also suggest that Pierolapithecus EDJ is closer to that of Dryopithecus for the M 1 and M 2 than Anoiapithecus is (Figs. 2A, B and3A, B). However, the three 'S.' occidentalis molars exhibit thick enamel (3D relative enamel thickness [3D RET]: 17.16-20.63), overlapping with the range of Pierolapithecus (3D RET: 13.24-18.14), whereas both Dryopithecus (3D RET: 10.96-12.81) and Anoiapithecus show thin enamel (3D RET: 11.40-14.26;[START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. If IPS1826+1827 and IPS41734 belonged to one of the taxa recognized here, both signals of the EDJ and enamel thickness would suggest that they would more likely represent Pierolapithecus than Anoiapithecus. Nevertheless, no definitive attribution can be given to these fossils until more mandibular remains belonging to the latter two genera are recovered and analyzed.

The Late Miocene Hispanopithecus was considered as a junior subjective synonym of Dryopithecus for years (e.g., [START_REF] Harrison | Some observations on the Miocene hominoids from Spain[END_REF][START_REF] Andrews | Distribution and biochronology of European and Southwest Asian Miocene catarrhines[END_REF], until the genus was resurrected [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF]Moyà-Solà et al., 2009a) for both Hispanopithecus laietanus and Hispanopithecus crusafonti. The later species, which includes the samples from Can Ponsic 1 and Teuleria del Firal, is classified in Hispanopithecus based on dental morphology because it shows some derived features with H. laietanus, coupled with a number of autapomorphic traits such as buccolingually broader upper molars [START_REF] Begun | Dryopithecus crusafonti sp. nov., a new Miocene hominoid species from Can Ponsic (Northeastern Spain)[END_REF][START_REF] Begun | European hominoids[END_REF][START_REF] Alba | Fossil apes from the Vallès-Penedès Basin[END_REF]. In terms of morphology of the molar EDJ, the dentine horns of Hispanopithecus are more peripherally located than in Dryopithecus (Fig. 1; [START_REF] Fortuny | Dryopithecine palaeobiodiversity in the Iberian Miocene revisited on the basis of molar endostructural morphology[END_REF]. Shape analyses of the EDJ show that the specimens attributed to Hispanopithecus plot close to Dryopithecus, and to a lesser extent to Anoiapithecus (Figs. 2345). The most surprising result of these analyses regards the high degree of variability of Hispanopithecus M2s. Even though two species are included in the genus (i.e., H. crusafonti and H. laietanus), they vary more than the extant great ape genera as represented in this study (Figs. 2E, 3E, 4E, and5E), as confirmed by permutation tests (Table 2). We acknowledge that the comparative sample of extant hominids included in this study might underestimate the actual degree of variation of each genus, but the same is true for the fossil samples. In addition, despite its limited size, the sample extant great apes represents male and female individuals of different species of Pan and Pongo (and possibly of Gorilla too, even though there is no contextual information for some specimens). For these reasons, the extant hominid sample is assumed to be representative of each genus, even though it likely underestimates their real range of variation due to the limits of sample size. For example, at least for Pongo M2s, two species (P. pygmaeus and P. abelii) are represented (SOM Table S2) and they are much less variable than those of Hispanopithecus. The high variability of the latter genus is mostly driven by IPS1082, which falls farther from the other four Hispanopithecus M2s. This could be interpreted in two different ways: 1) the M2 of IPS1802 is an outlier in terms of morphology, but belongs to Hispanopithecus; 2) IPS1802 belongs to another genus, but is closely related to Hispanopithecus. The small dimensions of this specimen compared with the other H. laietanus lower molars (Alba et al., 2012c) could also indicate that it belongs to a female of Hispanopithecus, but it would mean that sexual dimorphism in molar shape (especially at the EDJ level) would be higher than in extant great apes and the other dryopithecines, which is unlikely. It is noteworthy that IPS1802 (a mandibular fragment with M1-M3) was planned to be the holotype of Rahonapithecus sabadellensis, a nomen dubium because Crusafont-Pairó andHürzeler (1961, 1969) never described them (Fortuny et al., 2021, and references therein).

Pickford (2012) considered this specimen (as well as the holotype of 'S.' occidentalis) to belong to Neopithecus brancoi, which is here considered a nomen dubium (see also Moyà-Solà et al., 2009a;[START_REF] Begun | Fossil record of Miocene hominoids[END_REF][START_REF] Alba | A new dryopithecine mandibular fragment from the middle Miocene of Abocador de Can Mata and the taxonomic status of 'Sivapithecus' occidentalis from Can Vila (Vallès-Penedès Basin, NE Iberian Peninsula)[END_REF]. Nevertheless, this specimen hints at the possibility that some of the Middle Miocene genera recorded at Abocador de Can Mata persisted into the Vallesian and co-occurred with Hispanopithecus at Can Llobateres.

The phylogenetic relationships of the Iberian Miocene dryopithecines are still debated (see review in [START_REF] Almécija | Fossil apes and human evolution[END_REF]. Pierolapithecus, Anoiapithecus, and Dryopithecus have been either considered as stem hominids [START_REF] Moyà-Solà | Pierolapithecus catalaunicus, a new Middle Miocene great ape from Spain[END_REF], 2009b;[START_REF] Pugh | Phylogenetic analysis of Middle-Late Miocene apes[END_REF], stem pongines, (Pérez de los [START_REF] De Los Ríos | The nasal and paranasal architecture of the Middle Miocene ape Pierolapithecus catalaunicus (Primates: Hominidae): Phylogenetic implications[END_REF] or hominines [START_REF] Begun | Miocene hominids and the origins of the African apes and humans[END_REF]. In turn, Hispanopithecus has been variably considered a stem pongine [START_REF] Moyà-Solà | New partial cranium of Dryopithecus Lartet, 1863 (Hominoidea, Primates) from the upper Miocene of Can Llobateres, Barcelona, Spain[END_REF], a stem hominine [START_REF] Begun | European Miocene hominids and the origin of the African ape and human clade[END_REF], or a stem hominid (Moyà-Solà et al., 2009b). A recent cladistic analysis of Middle to Late Miocene hominoids based on 274 dental and skeletal traits found dryopithecines (excluding Ouranopithecus, Graecopithecus, and Oreopithecus) to be no more closely to hominines than to pongines and supported the Middle Miocene dryopithecins as being less derived than the Late Miocene hispanopithecins [START_REF] Pugh | Phylogenetic analysis of Middle-Late Miocene apes[END_REF]. A study investigating the phylogenetic signal of the inner ear morphology in primates indicated that the hispanopithecin genera Hispanopithecus and Rudapithecus show closest affinities in vestibular morphology with Pan but also with the inferred morphology for the last common ancestors of crown hominines and crown hominids, suggesting that such morphology is plesiomorphic (Urciuoli et al., 2021b). Another study based on the EDJ of primate M1s showed that this structure holds a very strong phylogenetic signal and can be used, in addition to the inner ear, to investigate evolutionary relationships (Zanolli et al., 2022b).

Posterior probabilities computed for the dryopithecine specimens in the bgPCA and CVA of the present study indicate closer shape similarities with Pongo for most taxa and tooth positions, even if a few specimens are closer to Pan (Table 1). However, as in the case of the aforementioned inner ear similarities with Pan, the EDJ results cannot be taken as suggesting a closer phylogenetic link with pongines without a proper phylogenetic analysis evaluating the polarity of change so as to discern if these features are primitive for hominids or derived for pongines. The study of the EDJ in other European dryopithecine taxa, such as Rudapithecus and Danuvius [START_REF] Begun | Dryopithecins, Darwin, de Bonis, and the European origin of the African apes and human clade[END_REF][START_REF] Begun | Fossil record of Miocene hominoids[END_REF][START_REF] Böhme | A new Miocene ape and locomotion in the ancestor of great apes and humans[END_REF], or specimens of doubtful taxonomic allocation (such as the holotype of N. brancoi), will be required to better understand the evolution of this group during the Miocene. Abbreviations: A = Anoiapithecus; D = Dryopithecus; P = Pierolapithecus; So = 'Sivapithecus' occidentalis species inquirenda.

a Variation in dryopithecines exceeds that seen in extant apes when p < 0.05. Probabilities lower than 0.05 are bolded.

  CVA analyses are consistent with each other and confirm that the groups observed in the bgPCA and CVA are not spurious. In both the bgPCA and CVA, the first component separates taxa based on EDJ height (and in particular dentine horn elevation), with Gorilla showing the highest dentine horns, Pongo the lowest, and Pan being intermediate (Figs. 2 and 3). The second component tends to discriminate the more centrally-positioned dentine horns of Pongo and Gorilla from those of Pan. The bgPCA and CVA plots show that the Miocene specimens are distributed in a distinct part of the morphospace, generally near Pongo, but sometimes intermediate between Pongo and Pan, and less frequently close to Pan (Figs. 2

  , permutation tests indicate that the single-genus hypothesis can be rejected for Anoiapithecus-Dryopithecus based on the M 2 and for Dryopithecus-Pierolapithecus (and Anoitapithecus-Pierolapithecus except when compared with Pongo in the bgPCA results) based on the M 3 . Permutation tests based on lower molars are of less utility because they are unknown for Pierolapithecus and only the M1 is available for Anoiapithecus, but they indicate that the variation of composite samples including Dryopithecus and 'S.' occidentalis do not exceed that of extant great ape genera for either the M2 or the M3.

Figure 1 .

 1 Figure 1. Main nonmetric features distinguishing between the Miocene dryopithecine genera at

Figure 2 .

 2 Figure 2. Bivariate plot of the between-group principal component 2 (bgPC2) against the

Figure 3 .

 3 Figure 3. Bivariate plot of the between-group principal component 2 (bgPC2) against the

Figure 4 .

 4 Figure 4. Plots of the Euclidian distances between specimens of the Miocene dryopithecines

Figure 5 .

 5 Figure 5. Plots of the Euclidian distances between specimens of the Miocene dryopithecines

Table 2

 2 Results of permutation tests, given as both probabilities (interpreted as p-values) and frequencies (within parentheses), based on the between-group principal component analysis (bgPCA) and canonical variate analysis (CVA) comparing the intrageneric variation of dryopithecine genera with that of extant great apes. a

	Miocene				bgPCA			CVA
		Tooth n
	genus			Gorilla	Pan	Pongo	Gorilla	Pan	Pongo
	A	M 1	4 0.67 (140/210) 0.98 (206/210) 0.99 (208/210) 0.67 (141/210) 0.99 (208/210)	1 (209/210)
	H	M 1	3 0.48 (58/120) 0.88 (106/120) 0.93 (112/120) 0.54 (65/120) 0.94 (113/120) 0.97 (116/120)
	D	M 2	2	0.47 (21/45)	0.40 (18/45)	0.47 (21/45)	0.96 (43/45)	0.76 (34/45)	0.87 (39/45)
	H	M 2	4 0.76 (159/210) 0.71 (148/210) 0.69 (145/210) 0.86 (180/210) 0.50 (105/210) 0.64 (135/210)
	P	M 2	2	0.64 (29/45)	0.62 (28/45)	0.62 (28/45)	0.87 (39/45)	0.71 (32/45)	0.80 (36/45)
	H	M 3	5	0 (0/252)	0 (0/252)	0.39 (97/252)	0 (0/252)	0 (0/252)	0.65 (164/252)
	A	M1	2	0.80 (36/45)	0.80 (36/45)	0.82 (37/45)	0.73 (33/45)	0.73 (33/45)	0.87 (39/45)
	H	M1	3 0.93 (112/120) 0.98 (118/120) 0.98 (117/120) 0.52 (62/120)	0.65 (78/120) 0.84 (101/120)
	D	M2	2	0.22 (10/45)	0.49 (22/45)	0.49 (22/45)	0.38 (17/45)	0.58 (26/45)	0.64 (29/45)
	H	M2	6	0 (0/210)	0.02 (5/210)	0.33 (69/210)	0 (0/210)	0 (0/210)	0 (0/210)
	So	M2	2	0.93 (42/45)	0.96 (43/45)	0.93 (42/45)	0.82 (37/45)	0.89 (40/45)	0.93 (42/45)
	D	M3	2	0.09 (4/45)	0.11 (5/45)	0.22 (10/45)	0.24 (11/45)	0.53 (24/45)	0.53 (24/45)
	H	M3	3 0.18 (21/120)	0.28 (33/120)	0.45 (54/120)	0.23 (27/120)	0.47 (56/120)	0.43 (51/120)

Table 3

 3 Results of permutation tests, given as both probabilities (interpreted as p-values) and frequencies (within parentheses), based on the between-group principal component analysis (bgPCA) and canonical variate analysis (CVA) comparing the variation of combined dryopithecine samples with the intrageneric variation of extant great apes. a

	Miocene	bgPCA
	Tooth	n
	genera

Acknowledgments

For access to comparative material, we sincerely thank P. Bayle, A. Beaudet, J. Braga, E.

Gilissen, M. Landreau, A. Mazurier, N. Mémoire, R. Macchiarelli. We thank Sergio Llácer for image processing, and Sebastià Calzada for the loan of specimens housed at the MGSB. We gratefully acknowledge support from the CNRS/IN2P3 Computing Center (Lyon, France) for providing computing and data-processing resources needed for this work. This research benefited from the scientific framework of the University of Bordeaux's IdEx "Investments for the Future" program / GPR "Human Past". This paper is part of R+D+I projects PID2020-116908GB-I00, PID2020-117118GB-I00 and PID2020-117289GB-I00, funded by the Spanish Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033/), as well as a Ramón y Cajal grant to J.F. (RYC2021-032857-I) financed by the Spanish Agencia Estatal de Investigación (MCIN/AEI/10.13039/501100011033) and the European Union "NextGenerationEU" / PRTR. Research has also been funded by the French CNRS, CERCA Programme/Generalitat de Catalunya, predoctoral fellowship (Agència de Gestió d'Ajuts Universitaris i de Recerca, Generalitat de Catalunya) to Fl.B., and the Regione Friuli-Venezia Giulia (ICTP/Elettra EXACT Project) in the frame of the SAPIENS Project funded by the Centro Fermi. J.F. and D.M.A. are members of consolidated research groups 2017 SGR 086 and 2017 SGR 116, respectively.

Finally, we thank the co-Editor-in-Chief (Andrea Taylor), the Associate Editor, and three anonymous reviewers for their comments that helped improve a previous version of this manuscript.

Table 1

Typicality probabilities of the investigated dryopithecine specimens with respect to the extant great apes based on the between-group principal component analysis (bgPCA) Abbreviations: L = left; R = right; A = Anoiapithecus; D = Dryopithecus; P = Pierolapithecus; So = 'Sivapithecus' occidentalis species inquirenda.

a These probabilities denote the likelihood that the score of each fossil specimen fits with a particular group, not the likelihood of group membership in each of the a priori defined groups given a particular score. The highest probabilities (above statistical threshold of 0.05) are highlighted in bold for each fossil specimen.

Abbreviations: A = Anoiapithecus; D = Dryopithecus; P = Pierolapithecus; So = 'Sivapithecus' occidentalis species inquirenda.

a Variation in dryopithecines exceeds that seen in extant apes when p < 0.05. Probabilities lower than 0.05 are bolded.