Pliopithecoids are an extinct group of catarrhine primates from the Miocene of Eurasia. More than... more Pliopithecoids are an extinct group of catarrhine primates from the Miocene of Eurasia. More than fifty years ago, they were linked to hylobatids due to some morphological similarities, but most subsequent studies have supported a stem catarrhine status, due to the retention of multiple plesiomorphic features (e.g., the ectotympanic morphology) relative to crown catarrhines. More recently, some morphological similarities to hominoids have been noted, raising the question of whether they could be stem members of this clade. To re-evaluate these competing hypotheses, we examine the morphology of the semicircular canals of the bony labyrinth of the middle Miocene pliopithecid Epipliopithecus vindobonensis. The semicircular canals are suitable to test between these hypotheses derived than Aegyptopithecus due to the possession of a crown catarrhine synapomorphy (i.e., the rounded anterior canal), combined with the lack of other catarrhine and any hominoid synapomorphies. Some similarities with hylobatids and atelids are interpreted as homoplasies likely related to positional behavior. The semicircular canal morphology of Epipliopithecus thus supports the common view that pliopithecoids are stem catarrhines.
This work has been funded by the Agencia Estatal de Investigación-European Regional Development F... more This work has been funded by the Agencia Estatal de Investigación-European Regional Development Fund of the European Union (CGL2016-76431-P and CGL2017-82654-P, AEI/FEDER-UE), the Generalitat de Catalunya (CERCA Program and consolidated research groups 2017 SGR 086 and 2017 SGR 116), and French CNRS. Fieldwork at ACM was defrayed by CESPA Gestión de Residuos S.A.U. Microtomographic scans of the fossil specimens were realized at the Multidisciplinary Laboratory of the "Abdus Salam" International Centre for Theoretical Physics (under the auspices of the SAPIENS Project funded by the Centro Fermi). We thank S. Llàcer for image processing, S. Calzada for the loan of specimens housed at the MGSB, C. Argot for access to specimens housed at the MNHN, N. Mémoire and M. Landreau for access to specimens housed at the MHNB, P. Bayle for the CT scans of the Harlé specimens, J. Braga and the MNHN for access to CT scans of HGP1, and Eileen Westwig for access to extant comparative material from the under her care at the AMNH. We further acknowledge the collaboration of the Centre de Restauració i Interpretació Paleontològica (CRIP; Ajuntament dels Hostalets de Pierola) and the Servei d'Arqueologia i Paleontologia of the Generalitat de Catalunya. We thank the Editor
Castell de Barberà, located in the Vallès-Penedès Basin (NE Iberian Peninsula), is one of the few... more Castell de Barberà, located in the Vallès-Penedès Basin (NE Iberian Peninsula), is one of the few European sites where pliopithecoids (Barberapithecus) and hominoids (cf. Dryopithecus) co-occur. The dating of this Miocene site has proven controversial. A latest Aragonian (MN7+8, ca. 11.88-11.18 Ma) age was long accepted by most authors, despite subsequent reports of hipparionin remains that signaled a Vallesian age. On the latter basis, Castell de Barberà was recently correlated to the early Vallesian (MN9, ca. 11.18-10.3 Ma) on tentative grounds. Uncertainties about the provenance of the Hippotherium material and the lack of magnetostratigraphic data precluded more accurate dating. After decades of inactivity, fieldwork was resumed in 2014-2015 at Castell de Barberà, including the original layer (CB-D) that in the past delivered most of the fossils. Here we report magnetostratigraphic results for the original outcrop and another nearby section. Our results indicate that CB-D is located in a normal polarity magnetozone at about midheight of a short (~20 m-thick) stratigraphic section. The composite magnetostratigraphic section (~50 m) has as many as four to six magnetozones. These multiple reversals, coupled with the in situ recovery of a Hippotherium humerus from CB-D in 2015, make it very unlikely the correlation of any of the sampled normal polarity magnetozones with the long normal polarity subchron C5n.2n (11.056-9.984 Ma), which is characteristic of the early Vallesian. Our results support instead a correlation of CB-D with C5r.1n (11.188-11.146 Ma), where the Aragonian/Vallesian boundary is situated, and therefore indicate an earliest Vallesian age of~11.2 Ma for Castell de Barberà. Our results settle the longstanding debate about the Aragonian vs. Vallesian age of this site, which appears roughly coeval with the Creu de Conill 20 locality (11.18 Ma), where hipparionins are first recorded in the Vallès-Penedès Basin.
In the Iberian Peninsula, Miocene apes (Hominoidea) are generally rare and mostly restricted to t... more In the Iberian Peninsula, Miocene apes (Hominoidea) are generally rare and mostly restricted to the Vallès-Penedès Basin. Here we report a new hominoid maxillary fragment with M from this basin. It was surface-collected in March 2017 from the site of Can Pallars i Llobateres (CPL, Sant Quirze del Vallès), where fossil apes had not been previously recorded. The locality of provenance (CPL-M), which has delivered no further fossil remains, is located very close (ca. 50 m) to previously known CPL outcrops, and not very far (ca. 500 m in NW direction) from the classical hominoid-bearing locality of Can Poncic 1. Here we describe the new fossil and, based on the size and proportions of the M, justify its taxonomic attribution to Hispanopithecus cf. laietanus, a species previously recorded from several Vallesian sites of the Vallès-Penedès Basin. Based on the associated mammalian fauna from CPL, we also provide a biochronological dating and a paleoenvironmental reconstruction for the site...
Miocene apes display a mosaic of primitive and derived hominoid features conferring them a body p... more Miocene apes display a mosaic of primitive and derived hominoid features conferring them a body plan with no modern locomotor analogs. Thus, the external morphology of the proximal femur in available fossil apes most closely approaches the extant ape condition. However, femoral mechanical properties and internal structure in extinct apes are less well known, even though they are essential to understand the evolution of loading regimes at the hominid hip joint. W e analyzed the biomechanical properties of the proximal femur IPS41724 from ACM/C3- Az (11.9 Ma, NE Iberian Peninsula), the oldest femur attributed to a fossil great ape (cf. Dryopithecus fontani). Externally, this femur combines primitive (e.g., laterally protruding greater trochanter and presence of third trochanter) and derived features (e.g., large and round head and high neck-shaft angle). Unlike in extant apes, the internal structure of the neck in IPS41724 exhibits a generalized monkey-like asymmetric distribution of ...
The chronology of the first human dispersal out of Africa and the ecological role of the genus Ho... more The chronology of the first human dispersal out of Africa and the ecological role of the genus Homo in Europe as a scavenger or an active hunter during the late Early Pleistocene are two of the paleoanthropological topics most hotly debated during the last decades. The earliest human occurrences in Western Europe are recorded in the Iberian Peninsula by the late Villafranchian (1.4e1.2 Ma), during a period of climatic stability. However, currently available taphonomic and paleoecological data suggest a direct and intense competition for food resources between these human populations and the large scavenging hyaenid Pachycrocuta brevirostris. The Villafranchian was followed by the Epivillafranchian (ca. 1.2e0.8 Ma), a period of climatic instability dominated by several strong glacial periods. The evidence from the Vallparadís Section reported here suggests that such unstable climatic conditions did not affect to a great extent the composition of the large mammal assemblages and, particularly, that of the carnivore guild. Based on the impressive record of carnivoran remains recovered from the Vallparadís Section and the taphonomic interpretation of this assemblage, we suggest that the putative direct competition between early Homo and large carnivores, especially P. brevirostris, persisted throughout the late Villafranchian and the Epivillafranchian.
Skinner and colleagues (Research Article, 23 January 2015, p. 395), based on metacarpal trabecula... more Skinner and colleagues (Research Article, 23 January 2015, p. 395), based on metacarpal trabecular bone structure, argue that Australopithecus africanus employed human-like dexterity for stone tool making and use 3 million years ago. However, their evolutionary and biological assumptions are misinformed, failing to refute the previously existing hypothesis that human-like manipulation preceded systematized stone tool manufacture, as indicated by the fossil record.
Here we describe the vertebral fragments from the partial skeleton IPS18800 of the fossil great a... more Here we describe the vertebral fragments from the partial skeleton IPS18800 of the fossil great ape Hispanopithecus laietanus (Hominidae: Dryopithecinae) from the late Miocene (9.6 Ma) of Can Llobateres 2 (Vallès-Penedès Basin, Catalonia, Spain). The eight specimens (IPS18800.5-IPS18800.12) include a fragment of thoracic vertebral body, three partial bodies and four neural arch fragments of lumbar vertebrae. Despite the retention of primitive features (moderately long lumbar vertebral bodies with slightly concave ventrolateral sides), these specimens display a suite of derived, modern hominoid-like features: thoracic vertebrae with dorsally-situated costal foveae; lumbar vertebrae with non-ventrally-oriented transverse processes originating from a robust pedicle, caudally-long laminae with caudally-oriented spinous process, elliptical end-plates, and moderately stout bodies reduced in length and with no ventral keel. These features, functionally related to orthograde behaviors, are ...
Información del artículo Intervención paleontológica en la Autovía Orbital de Barcelona B-40, tra... more Información del artículo Intervención paleontológica en la Autovía Orbital de Barcelona B-40, tramo Olesa de Montserrat - Viladecavalls: resultados preliminares.
The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional beh... more The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional behavior and locomotion of these taxa based on isolated elements only. The fossil great ape Pierolapithecus catalaunicus (IPS 21350 skeleton; 11.9 Ma) exhibits a relatively wide and shallow thorax with moderate hand length and phalangeal curvature, dorsally-oriented metacarpophalangeal joints, and loss of ulnocarpal articulation. This evidence reveals enhanced orthograde postures without modern ape-like below-branch suspensory adaptations. Therefore, it has been proposed that natural selection enhanced vertical climbing (and not suspension per se) in Pierolapithecus catalaunicus. Although limb long bones are not available for this species, its patella (IPS 21350.37) can potentially provide insights into its knee function and thus on the complexity of its total morphological pattern. Here we provide a detailed description and morphometric analyses of IPS 21350.37, which are based on four external dimensions intended to capture the overall patellar shape. Our results reveal that the patella of Pierolapithecus is similar to that of extant great apes: proximodistally short, mediolaterally broad and anteroposteriorly thin. Previous biomechanical studies of the anthropoid knee based on the same measurements proposed that the modern great ape patella reflects a mobile knee joint while the long, narrow and thick patella of platyrrhine and especially cercopithecoid monkeys would increase the quadriceps moment arm in knee extension during walking, galloping, climbing and leaping. The patella of Pierolapithecus differs not only from that of monkeys and hylobatids, but also from that of basal hominoids (e.g., Proconsul and Nacholapithecus), which display slightly thinner patellae than extant great apes (the previously-inferred plesiomorphic hominoid condition). If patellar shape in Pierolapithecus is related to modern great ape-like knee function, our results suggest that increased knee mobility might have originally evolved in relation to enhanced climbing capabilities in great apes (such as specialized vertical climbing).
Orrorin tugenensis (Kenya, ca. 6 Ma) is one of the earliest putative hominins. Its proximal femur... more Orrorin tugenensis (Kenya, ca. 6 Ma) is one of the earliest putative hominins. Its proximal femur, BAR 1002 0 00, was originally described as being very human-like, although later multivariate analyses showed an australopith pattern. However, some of its traits (for example, laterally protruding greater trochanter, medially oriented lesser trochanter and presence of third trochanter) are also present in earlier Miocene apes. Here, we use geometric morphometrics to reassess the morphological affinities of BAR 1002 0 00 within a large sample of anthropoids (including fossil apes and hominins) and reconstruct hominoid proximal femur evolution using squared-change parsimony. Our results indicate that both hominin and modern great ape femora evolved in different directions from a primitive morphology represented by some fossil apes. Orrorin appears intermediate between Miocene apes and australopiths in shape space. This evidence is consistent with femoral shape similarities in extant great apes being derived and homoplastic and has profound implications for understanding the origins of human bipedalism.
The first castorid remains from the area of els Hostalets de Pierola (l'Anoia, Catalonia, Spain),... more The first castorid remains from the area of els Hostalets de Pierola (l'Anoia, Catalonia, Spain), in the Valles-Penedes Basin, are described in this article. These fossil remains from Abocador de Can Mata (ACM), including a nearly complete hemimandible, two maxillary fragments, and several isolated teeth from locality C4-C2 (Late Arago nian, MN7+8), as well as an almost complete femur from the similarly-aged locality C3-Ak, are attributed to the genus Chalicomys (= Palaeomys). Taxonomic and nomenclatural issues regarding this genus are discussed. An emended diag nosis of this genus is provided, and a new species, Chalicomys batalleri sp. nov., is described on the basis of the ACM/C4-C2 specimens. The femur from ACM/C3-Ak is also tentatively included within the hypodigm of the newly erected species. Paleobiological inferences on the locomotor repertoire of Chalicomys are made on the basis of femoral anatomy. It is concluded that, like living Castor, these extinct beavers were efficient swimmers, highly committed to aquatic locomotion, which propelled mainly by means of hind feet paddling. The presence of an extinct beaver with Castor-like aquatic adaptations in this area, together with the sedimentological evidence, suggests more humid conditions than previously thought, at least for a restricted to a short time interval, given the rarity of castorid remains elsewhere in the ACM stratigraphic series.
Pliopithecoids are an extinct group of catarrhine primates from the Miocene of Eurasia. More than... more Pliopithecoids are an extinct group of catarrhine primates from the Miocene of Eurasia. More than fifty years ago, they were linked to hylobatids due to some morphological similarities, but most subsequent studies have supported a stem catarrhine status, due to the retention of multiple plesiomorphic features (e.g., the ectotympanic morphology) relative to crown catarrhines. More recently, some morphological similarities to hominoids have been noted, raising the question of whether they could be stem members of this clade. To re-evaluate these competing hypotheses, we examine the morphology of the semicircular canals of the bony labyrinth of the middle Miocene pliopithecid Epipliopithecus vindobonensis. The semicircular canals are suitable to test between these hypotheses derived than Aegyptopithecus due to the possession of a crown catarrhine synapomorphy (i.e., the rounded anterior canal), combined with the lack of other catarrhine and any hominoid synapomorphies. Some similarities with hylobatids and atelids are interpreted as homoplasies likely related to positional behavior. The semicircular canal morphology of Epipliopithecus thus supports the common view that pliopithecoids are stem catarrhines.
This work has been funded by the Agencia Estatal de Investigación-European Regional Development F... more This work has been funded by the Agencia Estatal de Investigación-European Regional Development Fund of the European Union (CGL2016-76431-P and CGL2017-82654-P, AEI/FEDER-UE), the Generalitat de Catalunya (CERCA Program and consolidated research groups 2017 SGR 086 and 2017 SGR 116), and French CNRS. Fieldwork at ACM was defrayed by CESPA Gestión de Residuos S.A.U. Microtomographic scans of the fossil specimens were realized at the Multidisciplinary Laboratory of the "Abdus Salam" International Centre for Theoretical Physics (under the auspices of the SAPIENS Project funded by the Centro Fermi). We thank S. Llàcer for image processing, S. Calzada for the loan of specimens housed at the MGSB, C. Argot for access to specimens housed at the MNHN, N. Mémoire and M. Landreau for access to specimens housed at the MHNB, P. Bayle for the CT scans of the Harlé specimens, J. Braga and the MNHN for access to CT scans of HGP1, and Eileen Westwig for access to extant comparative material from the under her care at the AMNH. We further acknowledge the collaboration of the Centre de Restauració i Interpretació Paleontològica (CRIP; Ajuntament dels Hostalets de Pierola) and the Servei d'Arqueologia i Paleontologia of the Generalitat de Catalunya. We thank the Editor
Castell de Barberà, located in the Vallès-Penedès Basin (NE Iberian Peninsula), is one of the few... more Castell de Barberà, located in the Vallès-Penedès Basin (NE Iberian Peninsula), is one of the few European sites where pliopithecoids (Barberapithecus) and hominoids (cf. Dryopithecus) co-occur. The dating of this Miocene site has proven controversial. A latest Aragonian (MN7+8, ca. 11.88-11.18 Ma) age was long accepted by most authors, despite subsequent reports of hipparionin remains that signaled a Vallesian age. On the latter basis, Castell de Barberà was recently correlated to the early Vallesian (MN9, ca. 11.18-10.3 Ma) on tentative grounds. Uncertainties about the provenance of the Hippotherium material and the lack of magnetostratigraphic data precluded more accurate dating. After decades of inactivity, fieldwork was resumed in 2014-2015 at Castell de Barberà, including the original layer (CB-D) that in the past delivered most of the fossils. Here we report magnetostratigraphic results for the original outcrop and another nearby section. Our results indicate that CB-D is located in a normal polarity magnetozone at about midheight of a short (~20 m-thick) stratigraphic section. The composite magnetostratigraphic section (~50 m) has as many as four to six magnetozones. These multiple reversals, coupled with the in situ recovery of a Hippotherium humerus from CB-D in 2015, make it very unlikely the correlation of any of the sampled normal polarity magnetozones with the long normal polarity subchron C5n.2n (11.056-9.984 Ma), which is characteristic of the early Vallesian. Our results support instead a correlation of CB-D with C5r.1n (11.188-11.146 Ma), where the Aragonian/Vallesian boundary is situated, and therefore indicate an earliest Vallesian age of~11.2 Ma for Castell de Barberà. Our results settle the longstanding debate about the Aragonian vs. Vallesian age of this site, which appears roughly coeval with the Creu de Conill 20 locality (11.18 Ma), where hipparionins are first recorded in the Vallès-Penedès Basin.
In the Iberian Peninsula, Miocene apes (Hominoidea) are generally rare and mostly restricted to t... more In the Iberian Peninsula, Miocene apes (Hominoidea) are generally rare and mostly restricted to the Vallès-Penedès Basin. Here we report a new hominoid maxillary fragment with M from this basin. It was surface-collected in March 2017 from the site of Can Pallars i Llobateres (CPL, Sant Quirze del Vallès), where fossil apes had not been previously recorded. The locality of provenance (CPL-M), which has delivered no further fossil remains, is located very close (ca. 50 m) to previously known CPL outcrops, and not very far (ca. 500 m in NW direction) from the classical hominoid-bearing locality of Can Poncic 1. Here we describe the new fossil and, based on the size and proportions of the M, justify its taxonomic attribution to Hispanopithecus cf. laietanus, a species previously recorded from several Vallesian sites of the Vallès-Penedès Basin. Based on the associated mammalian fauna from CPL, we also provide a biochronological dating and a paleoenvironmental reconstruction for the site...
Miocene apes display a mosaic of primitive and derived hominoid features conferring them a body p... more Miocene apes display a mosaic of primitive and derived hominoid features conferring them a body plan with no modern locomotor analogs. Thus, the external morphology of the proximal femur in available fossil apes most closely approaches the extant ape condition. However, femoral mechanical properties and internal structure in extinct apes are less well known, even though they are essential to understand the evolution of loading regimes at the hominid hip joint. W e analyzed the biomechanical properties of the proximal femur IPS41724 from ACM/C3- Az (11.9 Ma, NE Iberian Peninsula), the oldest femur attributed to a fossil great ape (cf. Dryopithecus fontani). Externally, this femur combines primitive (e.g., laterally protruding greater trochanter and presence of third trochanter) and derived features (e.g., large and round head and high neck-shaft angle). Unlike in extant apes, the internal structure of the neck in IPS41724 exhibits a generalized monkey-like asymmetric distribution of ...
The chronology of the first human dispersal out of Africa and the ecological role of the genus Ho... more The chronology of the first human dispersal out of Africa and the ecological role of the genus Homo in Europe as a scavenger or an active hunter during the late Early Pleistocene are two of the paleoanthropological topics most hotly debated during the last decades. The earliest human occurrences in Western Europe are recorded in the Iberian Peninsula by the late Villafranchian (1.4e1.2 Ma), during a period of climatic stability. However, currently available taphonomic and paleoecological data suggest a direct and intense competition for food resources between these human populations and the large scavenging hyaenid Pachycrocuta brevirostris. The Villafranchian was followed by the Epivillafranchian (ca. 1.2e0.8 Ma), a period of climatic instability dominated by several strong glacial periods. The evidence from the Vallparadís Section reported here suggests that such unstable climatic conditions did not affect to a great extent the composition of the large mammal assemblages and, particularly, that of the carnivore guild. Based on the impressive record of carnivoran remains recovered from the Vallparadís Section and the taphonomic interpretation of this assemblage, we suggest that the putative direct competition between early Homo and large carnivores, especially P. brevirostris, persisted throughout the late Villafranchian and the Epivillafranchian.
Skinner and colleagues (Research Article, 23 January 2015, p. 395), based on metacarpal trabecula... more Skinner and colleagues (Research Article, 23 January 2015, p. 395), based on metacarpal trabecular bone structure, argue that Australopithecus africanus employed human-like dexterity for stone tool making and use 3 million years ago. However, their evolutionary and biological assumptions are misinformed, failing to refute the previously existing hypothesis that human-like manipulation preceded systematized stone tool manufacture, as indicated by the fossil record.
Here we describe the vertebral fragments from the partial skeleton IPS18800 of the fossil great a... more Here we describe the vertebral fragments from the partial skeleton IPS18800 of the fossil great ape Hispanopithecus laietanus (Hominidae: Dryopithecinae) from the late Miocene (9.6 Ma) of Can Llobateres 2 (Vallès-Penedès Basin, Catalonia, Spain). The eight specimens (IPS18800.5-IPS18800.12) include a fragment of thoracic vertebral body, three partial bodies and four neural arch fragments of lumbar vertebrae. Despite the retention of primitive features (moderately long lumbar vertebral bodies with slightly concave ventrolateral sides), these specimens display a suite of derived, modern hominoid-like features: thoracic vertebrae with dorsally-situated costal foveae; lumbar vertebrae with non-ventrally-oriented transverse processes originating from a robust pedicle, caudally-long laminae with caudally-oriented spinous process, elliptical end-plates, and moderately stout bodies reduced in length and with no ventral keel. These features, functionally related to orthograde behaviors, are ...
Información del artículo Intervención paleontológica en la Autovía Orbital de Barcelona B-40, tra... more Información del artículo Intervención paleontológica en la Autovía Orbital de Barcelona B-40, tramo Olesa de Montserrat - Viladecavalls: resultados preliminares.
The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional beh... more The mosaic nature of the Miocene ape postcranium hinders the reconstruction of the positional behavior and locomotion of these taxa based on isolated elements only. The fossil great ape Pierolapithecus catalaunicus (IPS 21350 skeleton; 11.9 Ma) exhibits a relatively wide and shallow thorax with moderate hand length and phalangeal curvature, dorsally-oriented metacarpophalangeal joints, and loss of ulnocarpal articulation. This evidence reveals enhanced orthograde postures without modern ape-like below-branch suspensory adaptations. Therefore, it has been proposed that natural selection enhanced vertical climbing (and not suspension per se) in Pierolapithecus catalaunicus. Although limb long bones are not available for this species, its patella (IPS 21350.37) can potentially provide insights into its knee function and thus on the complexity of its total morphological pattern. Here we provide a detailed description and morphometric analyses of IPS 21350.37, which are based on four external dimensions intended to capture the overall patellar shape. Our results reveal that the patella of Pierolapithecus is similar to that of extant great apes: proximodistally short, mediolaterally broad and anteroposteriorly thin. Previous biomechanical studies of the anthropoid knee based on the same measurements proposed that the modern great ape patella reflects a mobile knee joint while the long, narrow and thick patella of platyrrhine and especially cercopithecoid monkeys would increase the quadriceps moment arm in knee extension during walking, galloping, climbing and leaping. The patella of Pierolapithecus differs not only from that of monkeys and hylobatids, but also from that of basal hominoids (e.g., Proconsul and Nacholapithecus), which display slightly thinner patellae than extant great apes (the previously-inferred plesiomorphic hominoid condition). If patellar shape in Pierolapithecus is related to modern great ape-like knee function, our results suggest that increased knee mobility might have originally evolved in relation to enhanced climbing capabilities in great apes (such as specialized vertical climbing).
Orrorin tugenensis (Kenya, ca. 6 Ma) is one of the earliest putative hominins. Its proximal femur... more Orrorin tugenensis (Kenya, ca. 6 Ma) is one of the earliest putative hominins. Its proximal femur, BAR 1002 0 00, was originally described as being very human-like, although later multivariate analyses showed an australopith pattern. However, some of its traits (for example, laterally protruding greater trochanter, medially oriented lesser trochanter and presence of third trochanter) are also present in earlier Miocene apes. Here, we use geometric morphometrics to reassess the morphological affinities of BAR 1002 0 00 within a large sample of anthropoids (including fossil apes and hominins) and reconstruct hominoid proximal femur evolution using squared-change parsimony. Our results indicate that both hominin and modern great ape femora evolved in different directions from a primitive morphology represented by some fossil apes. Orrorin appears intermediate between Miocene apes and australopiths in shape space. This evidence is consistent with femoral shape similarities in extant great apes being derived and homoplastic and has profound implications for understanding the origins of human bipedalism.
The first castorid remains from the area of els Hostalets de Pierola (l'Anoia, Catalonia, Spain),... more The first castorid remains from the area of els Hostalets de Pierola (l'Anoia, Catalonia, Spain), in the Valles-Penedes Basin, are described in this article. These fossil remains from Abocador de Can Mata (ACM), including a nearly complete hemimandible, two maxillary fragments, and several isolated teeth from locality C4-C2 (Late Arago nian, MN7+8), as well as an almost complete femur from the similarly-aged locality C3-Ak, are attributed to the genus Chalicomys (= Palaeomys). Taxonomic and nomenclatural issues regarding this genus are discussed. An emended diag nosis of this genus is provided, and a new species, Chalicomys batalleri sp. nov., is described on the basis of the ACM/C4-C2 specimens. The femur from ACM/C3-Ak is also tentatively included within the hypodigm of the newly erected species. Paleobiological inferences on the locomotor repertoire of Chalicomys are made on the basis of femoral anatomy. It is concluded that, like living Castor, these extinct beavers were efficient swimmers, highly committed to aquatic locomotion, which propelled mainly by means of hind feet paddling. The presence of an extinct beaver with Castor-like aquatic adaptations in this area, together with the sedimentological evidence, suggests more humid conditions than previously thought, at least for a restricted to a short time interval, given the rarity of castorid remains elsewhere in the ACM stratigraphic series.
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