On the systematic position of the large-sized deer from Apollonia,Early Pleistocene,Greece

The revision of the large-sized deer association from the early Pleistocene site Apollonia (Early Pleistocene; Greece), revealed the presence of two species,Praemegaceros pliotarandoides (De Alessandri, 1903) and a giant representative of the genusArvernoceros. P. pliotarandoides (=Psekupsoceros orientalis Radulesco & Samson, 1967) is characterized by advanced dental morphology, lack of the middle antler tine, and dichotomously branched distal part of the antlers and is regarded as the direct forerunner of middle PleistoceneP. verticornis. The species attribution of the ApollonianArvernoceros is not clear enough because of the incomplete data, and for this reason we keep this form under the nameArvernoceros cf.verestchagini. The presence ofArvernoceros in Apollonia certainly extends its chronological occurrence to early Pleistocene and a new generic definition is proposed. Several taxonomic and systematic questions on early Pleistocene large-sized deer of Europe are also discussed.     

Taxonomic status of the hominine cranium KNM-ER 1813 (primates: Homininae) from the Plio/Pleistocene of Koobi Fora

The hominine cranium KNM-ER 1813, from the late Plio/Pleistocene of Koobi Fora, has been regarded recently by some authors as a female ofHomo habilis Leakey, Tobias, andNapier, 1964 and by others as an enigma. Reassessment of its cranial morphology, dental metrics, proportions, and a new detailed determination of its sex indicates that it does not conform with the diagnosis forH. habilis, and is probably a male. It is sympatric withH. habilis yet shows more primitive features and rather a closer affinity to the smaller, more primitive chronospeciesH. antiquus Ferguson, 1984, and is thus the first, nearly complete skull of our oldest known human ancestor.     

The mechanical significance of the occlusal geometry of great ape molars in food breakdown

Analyses of dental function are an essential component of the study of human evolution. However, with few exceptions, they have utilized the traditional analogizing method of comparative anatomy, and have assumed rather than demonstrated that proposed adaptive characters confer a performance benefit. Since food reduction is a mechanical process, it is appropriate to measure performance using mechanical parameters, specifically the ability of a given morphology to induce failure in food particle by either of the two major regimes: crush and shear, corresponding to simple stresses (tensile and compressive) and shear stress, respectively. We apply finite elements stress analysis to model the relationship between the angulation of the intercuspal occlusal surfaces in a “puncture crushing” mode of mastication. On the basis of morphological data acquired from sectioned great ape molars, we have predicted the nature, magnitude and distribution of stress in a standard food particle by models representing each morphotype. Results indicate that the blunt-cusped molars ofHomo, the gradually-sloping supporting (buccal) cusps but high-angled guiding (lingual) cusps of the lower molars ofPan, and the high angled occlusal surfaces ofGorillaare all more likely to fracture small food particles by shear, while the gradually sloping occlusal surfaces ofPongomolars are more likely to break them down by “crush”. Mechanisms of food failure induced by molars ofPanandHomowill vary according to the orientation of the tooth–food contacting surfaces, which in turn will vary according to the size of the food particle. These genera may be able to break food down either by shear or by “crush”.     

Revision of fossil hominid jaws from the plio/pleistocene of hadar,in ethiopia including a new species of the genusHomo (hominoidea: homininae)

The assignment of fossil hominoid jaws from the Plio/Pleistocene of Hadar to a single genus,Australopithecus Dart, 1925, is a misnomer. They are morphologically unrestricted to and inconsistent with the diagnosis and evolutionary trend ofAustralopithecus. The morphological pattern of four large jaws is indeed australopithecine and similar toA. africanus Dart, 1925, but six small jaws reveal a pre-habilis stage of dental development early in theHomo lineage. On the basis of their unique hominine dentition, they are reinterpreted as representing a new species,Homo antiquus n.sp.     

Macrodontia in Pleistocene humans from Europe as a feature of physiological acromegalosis: association with geomagnetic dipole field intensity

In a continuing investigation of acromegalosis in Pleistocene humans, macrodontia of the cheek teeth, estimated by their average summed occlusal areas (posterior ASOA), is related to geomagnetic field intensity of the Earth's main dipole (GMFI), measured in dipole moment units (DMU). The odontometric baseline derives from 2,111 teeth published for Europe, dated ca. 3000,000–5,000 years BP, grouped into twelve databases according to independent archeological and geological criteria. Most of the dental measurements are fromFrayer (1978) andWolpoff (1971, 1979, 1982). The GMFI baseline is adapted from the North Pacific deep-sea core data ofWollin et al. (1971), as in previos papers on hyperostosis (Ivanhoe, 1979) and progressive hypercrania (Ivanhoe, 1982). Parametric statistical analysis of thin human Pleistocene bioenvironmental association reveals (1) that two distinct, noncontemporaneous macrodontia lineages are present; (2) that posterior ASOA is a direct linear function of mean DMU; and (3) that time depth is not, by itself, a good predictor of macrodontia. Together, the combined GMFI, geological time depth, and specific lineage variables account for nearly 90% of the total variance in posterior ASOA. The earlier lineage, dated ca. 300,000–60,000 years BP, corresponding to advancedHomo erectus, preneandertals and early neandertals, and subdivided into two populations at about 130,000 years BP, is much more macrodont than the later lineage, corresponding to late neandertals through Mesolithicsapiens, subdivided into ten sample.s Reflecting concurrent changes in mean DMU, posterior ASOA fell in the Riss-Wurm interglacial, rose again to a peak in the main Wurm glacial stage, and fell gradually thereafter to approximate modern normal tooth sizes by the beginning of the Holocene. GMFI dependent variability of Pleistocene human macrodontia in Europe parallels closely that observed for hyperostosis in the northern hemisphere (Ivanhoe, 1979). The theory of Pleistocene human acromegalosis is discussed within the context of paleoanthropology, including aspects of the proposed geomagnetotrophic-neuroendocrine mechanism, and the question of rickets in the neandertals (Ivanhoe, 1970) is updated.     

Morphometric analysis ofMacaca arctoides andM. thibetana in relation to other macaque species

As a first step in reviewing the classification of the two stump-tailed macaque species,Macaca arctoides andM. thibetana, as compared with other species of the genusMacaca, 72 linear dental and cranial variables of 11 macaque species were examined by morphometric analyses. The results indicate that the two stump-tailed species are the largest of the macaques and although rather similar overall, they exhibit significant differences in the pattern of variation in most of the five skull regions as shown by Principal Components and Canonical Variate Analyses. Euclidean Distances based on Canonical Variate scores indicate that the females ofM. arctoides andM. thibetana are more widely separated than eight other pairs of macaque species, and that the separations of the respective males are greater than those of three other pairs of species. These findings are consistent withFooden's classification of the stump-tailed macaques as two separate species (Fooden, 1976;Fooden et al., 1985). The present results suggest, as other researchers have proposed on the basis of external features, biochemistry and genetics, that the two stump-tailed macaque species andM. assamensis are closely related. The results also tentatively imply associations withM. fuscata andM. sylvanus but these require further study. The findings have implications for the assessment of the various Chinese Pleistocene macaque fossils.     

A new species of the genusHomo (primates: Hominidae) from the Plio/Pleistocene of Koobi Fora,in Kenya

Reassessment of the hominine cranium, KNM-ER 1813, from the Plio/Pleistocene of Koobi Fora, in Kenya, shows that it is not a small-brained, extreme female variant ofH. habilis Leakey, Tobias, & Napier, 1964. Its cranial and dental morphology, morphometrics, and proportions do not conform with eitherH. habilis orH. antiquus Ferguson, 1984. On the basis of its distinctive morphological pattern and mensural gaps which distinguish it fromH. habilis andH. antiquus, the cranium KNM-ER 1813 is described as a common variant representing a male of a small-brained, intermediate population linkingH. habilis 1.83 Myr BP withH. antiquus 2.9 Myr BP, and a new paleospecies of the genusHomo. A key to the Homininae is provided and the phylogenetic relationship of KNM-ER 1813 toH. habilis andH. antiquus is discussed. This paper is dedicated to the memory of my wife,Grace, whose assistance will be sorely missed.     

Post-Pleistocene facial reduction,biomechanics and selection against morphologically complex teeth: A rejoinder to macchiarelli and bondioli

Macchiarelli & Bondioli (1984, 1986) argue that post-Pleistocene cranio-facial reduction cannot be explained by biomechanical factors related to change in the diet (Carlson, 1974;Carlson & Van Gerven, 1977) or to facial reduction related to the selective advantages of smaller, morphologically simpler teeth (Greene, 1967;Van Gerven, Armelagos & Rohr, 1977). Instead, they maintain that facial reduction is a mere side-effect of a reduction in overall body size. Our analysis of skeletal and facial reduction in post-Pleistocene Sudanese Nubia suggests thatMacchiarelli & Bondioli's interpretation is incorrect for two reasons. First, the reduction in facial morphology (at least since Mesolithic times) is greater by several orders of magnitude than the reduction in general body size. Second, the dentition not only shows a greater size reduction than does general body size, but a shifting pattern of dental reduction rather than a general decrease across all teeth.     

A new mobergellan (small shelly fossils) from the early middle cambrian of morocco and its significance

A new mobergellan genus and species,Tateltella ranoculata, is described from the early Middle Cambrian (Agdzian Stage) of Morocco. The new taxon is characterized by only four pairs of muscle scars and is furthermore distinguished from other mobergellans by its strongly concave shape and its distally rising muscle scars. The individual specimens ofTateltella ranoculata distinctly vary in size and display different ontogenetic stages. Juvenile, intermediate, and adult stages can be distinguished by means of the development of the muscle scars that differ in Position relative to the apex, size, and distinctness between individual stages. The shell ofT. ranoculata is composed of a succession of thin phosphatic lamellae separated by interlamellar gaps, presumably originally filled by organic material. The interlamellar gaps may be divided by septum-like structures producing discrete cavities. The specimens are the youngest mobergellans known so far and correlation of their stratigraphic position suggests a correspondence with the lower part of the Amgan stage of the Siberian Platform. In addition, they are the first reported mobergellans from the present day continent Africa. Other mobergellan taxa and mobergellan-like species are briefly reviewed and the genusHippoklosma Missarzhevsky, previously assigned to the Mobergellidae, is excluded from the family due to its different shell structure. An evolutionary trend of reduction in the number of muscle scars from 14 in the early Early Cambrian to only eight in the early Middle Cambrian is apparent among mobergellans.      

Revision of the subspecies ofAustralopithecus africanus (primates: Hominidae), including a new subspecies from the late pliocene of Ethiopia

The subspecies ofAustralopithecus africanus Dart, 1925 have been revised in a morphological and statistical analysis. Four subspecific names were previously proposed, but only one was found to be valid. The subspeciesA. africanus transvaalensis (Broom, 1936), from the Plio/Pleistocene of South Africa, cannot be sustained due to an insufficient sample, and is combined with the nominate race,A. a. africanus. The type ofA. africanus afarensis Tobias, 1980 is a mistake in identification and notA. africanus, but a pongid. The population ofA. africanus from the late Pliocene of Ethiopia does indeed represent a relatively small-toothed geographical race for which the nameA. africanus aethiopicus was conditionally proposed; and the lectotype for it, A.L. 288-1, is notA. africanus, but the type ofHomo antiquus Ferguson, 1984. The trinominalaethiopicus is thus unavailable for the Ethiopian race, which is redescribed as a new subspecies,A. africanus miodentatus n. ssp., and the mandible A.L. 266-1 is designated as the holotype.     

A new scolenaspidid (Osteostraci, Vertebrata) from the Lower Devonian of Podolia, Ukraine

Anew osteostracan genus and species,Victoraspis longicornualis n. gen., n. sp., is described based on material from Rakovets’, present day Ukraine. This new taxon shares characters with the two generaStensiopelta Denison, 1951 andZychaspis Janvier, 1985. A phylogenetic analysis supports the position ofVictoraspis as the sister group to a monophyleticStensiopelta, while the interrelationships of the various species ofZychaspis are poorly resolved. A morphometric analysis is carried out in an attempt to further resolve the taxonomic affinity. This analysis groups all examinedZychaspis species closely together, and further supports the establishment ofVictoraspis as separate genus.      

Reconstruction and re-evaluation of the skull ofHomo antiquus (hominoidea: Homininae) from Hadar

The skull ofHomo antiquus Ferguson, 1984, represented by cranial remains of a fossilized skeleton, A.L. 288-1, from the Plio/Pleistocene of Hadar in Ethiopia, is reconstructed and the procedure described. Re-evaluation of the skull shows that it is apparently the smallest, normal, unequivocal hominid skull known; and that its cranial morphology is not Australopithecine, but Hominine.     

Evolution of the second orangutan: phylogeny and biogeography of hominid origins

Aim To resolve the phylogeny of humans and their fossil relatives (collectively, hominids), orangutans (Pongo) and various Miocene great apes and to present a biogeographical model for their differentiation in space and time. Location Africa, northern Mediterranean, Asia. Methods Maximum parsimony analysis was used to assess phylogenetic relationships among living large‐bodied hominoids (= humans, chimpanzees, bonobos, gorillas, orangutans), and various related African, Asian and European ape fossils. Biogeographical characteristics were analysed for vicariant replacement, main massings and nodes. A geomorphological correlation was identified for a clade we refer to as the ‘dental hominoids’, and this correlation was used to reconstruct their historical geography. Results Our analyses support the following hypotheses: (1) the living large‐bodied hominoids represent a monophyletic group comprising two sister clades: humans + orangutans, and chimpanzees (including bonobos) + gorillas (collectively, the African apes); and (2) the human–orangutan clade (dental hominoids) includes fossil hominids (Homo, australopiths, Orrorin) and the Miocene‐age apes Hispanopithecus, Ouranopithecus, Ankarapithecus, Sivapithecus, Lufengpithecus, Khoratpithecus and Gigantopithecus (also Plio‐Pleistocene of eastern Asia). We also demonstrate that the distributions of living and fossil genera are largely vicariant, with nodes of geographical overlap or proximity between Gigantopithecus and Sivapithecus in Central Asia, and between Pongo, Gigantopithecus, Lufengpithecus and Khoratpithecus in East Asia. The main massing is represented by five genera and eight species in East Asia. The dental hominoid track is spatially correlated with the East African Rift System (EARS) and the Tethys Orogenic Collage (TOC). Main conclusions Humans and orangutans share a common ancestor that excludes the extant African apes. Molecular analyses are compromised by phenetic procedures such as alignment and are probably based on primitive retentions. We infer that the human–orangutan common ancestor had established a widespread distribution by at least 13 Ma. Vicariant differentiation resulted in the ancestors of hominids in East Africa and various primarily Miocene apes distributed between Spain and Southeast Asia (and possibly also parts of East Africa). The geographical disjunction between early hominids and Asian Pongo is attributed to local extinctions between Europe and Central Asia. The EARS and TOC correlations suggest that these geomorphological features mediated establishment of the ancestral range.     

Skeletal anatomy of the Late Cretaceous shark,Squalicorax (Neoselachii: Anacoracidae)

The paleobiology of the Cretaceous neoselachian shark,Squalicorax, has largely been based on isolated teeth. We examined partial and nearly complete skeletons of three species ofSqualicorax, S. falcatus (Aoassiz),S. kaupi (Agassiz), andS. pristodontus (Agassiz), that were collected from the U.S.A. These specimens suggest that the total body length (TL) ofS. falcatus typically measured 1.8–2.0 m, and probably did not exceed 3 m. Moderatesized individuals ofS. kaupi andS. pristodontus perhaps measured about 3 m TL. AlthoughS. pristodontus was the largest form among the three species examined, this taxon possessed a set of large jaws (with large but fewer teeth) relative to its body size compared toS. falcatus orS. kaupi. This suggests that tooth size is not an accurate indicator of the TL if one compares oneSqualicorax species to another. Neurocranial features suggest that the vision ofSqualicorax was not as acute as that of a contemporaneous macrophagous lamniform shark,Cretoxyrhina mantelli (Agassiz) , but olfaction ofSqualicorax may have been better thanC. mantelli. The morphology of placoid scales suggests thatSqualicorax was capable of fast swimming. New skeletal data support the view that the feeding dynamics ofSqualicorax was similar to the modern tiger shark (Galeocerdo Müller & Henle). The present data do not allow for exact ordinal placement, but, contrary to some previous interpretations,Squalicorax can be excluded from the Hexanchiformes and Orectolobiformes. The taxon should more appropriately be placed within the Lamniformes or Carcharhiniformes.      

Reappraisal of the taxonomic status of the cranium Stw 53 from the Plio/Pleistocene of Sterkfontein,in South Africa

A fossil skull, Stw 53, from the Plio/Pleistocene of Sterkfontein, in South Africa, has been referred toHomo habilis Leakey, Napier, andTobias, 1964. Reappraisal of its putative hominine affinity reveals a closer resemblance toAustralopithecus africanus Dart, 1925. The skull, as reconstructed, is too small forH. habilis; with no indication of brain expansion overA. africanus; has a facial angle outside the hominine range, but identical with that ofA. africanus; and whose teeth are not elongated but display buccolingual expansion. Although it was found in the same strata (Member 5) as stone tools, there is no causal connection. It has been dated faunistically at 2–1.5 my BP, but due to an unconformity it is suggested that it could be older. In spite of its late date, Stw 53 shows no intermediate characters which could support a trend towardsH. habilis orA. robustus Broom, 1938. It may, therefore, represent a relict population ofA. africanus.     

The Late Pleistocene Orangutan from Tham Prakai Phet: New discoveries

This paper describes the collection of isolated orangutan fossil teeth identified in the newly excavated material from Tham Prakai Phet, a site located in the Chaiyaphum Province in northeast Thailand. The collection is composed of 18 isolated teeth belonging to Pongo. The morphology of the upper and lower teeth is similar to that of fossil and extant orangutans from mainland Indochina and Indonesia. Only the wrinkles on the occlusal surface are less pronounced and sometimes simpler than extant orangutans. The dimensions of the teeth fall in the range of variation of fossil and extant specimens, but the distribution of the crown areas of the Tham Prakai Phet specimens fall above the mean value observed for extant orangutans. This new collection of continental orangutans confirms the persistence of this taxa in this part of Thailand up to the late Pleistocene, and provides new data useful for understanding the evolution of this hominoid and advance in the reconstitution of the evolutionary lineage of Pongo. The size of the sample from Tham Prakai Phet is not sufficient to determine an accurate taxonomic attribution; pending the increase of the current sample, we attribute the material to Pongo sp. (Pongo aff. weidenreichi).     

Model of a hypothetical protohominid dentition and its implications for hominid phylogeny

The complete dentition of the common ancestor ofAustralopithecus andHomo, intermediate between that of a pongid and a hominid, is virtually unknown. The maxillary dentition (P3-M2) ofRamapithecus brevirostris Lewis, 1934, a pongid from the Early Pliocene, and that of hominids from the Late Pliocene and Plio/Pleistocene is known. SinceR. brevirostris is probably ancestral to the hominids, a model of intermediate maxillary dentition (P3-M2) is extrapolated and described. The model represents a hypothetical protohominid dentition. It does not conform with the teeth ofAustralopithecus, but shows greater morphological affinity to hominine dentition and to 5 myo hominids. TheHomo lineage, therefore, may go back to the Middle Pliocene. According to the normal sequence of evolution, it is most unlikely thatAustralopithecus gave rise toHomo, but much more probable that a very early, generalizedHomo evolved into an advanced, specializedAustralopithecus.     

Dental agenesis as evidence of possible genetic isolation in the colobine monkey,Rhinopithecus roxellana

In a sample of 24 skulls of the rare colobine monkey of China,Rhinopithecus roxellana, agenesis of the permanent upper third premolar was observed in 8 specimens (33%). Two of the individuals (8% of the sample) showed unilateral agenesis, while six (25%) showed bilateral agenesis. All of the affected individuals appear to have originated from two areas in central Sichuan Province in China, Moupin (Baoxing) and Wen Chuan, that lie approximately 120 km apart on the western rim of the Sichuan Basin. In this species agenesis of the upper third premolar was generally accompanied by rotation of the upper fourth premolar, but not by any other observable variation in tooth size, morphology, or number. Further, dental agenesis in this species appears to have had no effect craniofacial morphology. In certain human populations, a high prevalence of dental agenesis has been associated with small population effects and genetic isolation. Premolar agenesis inR. roxellana can probably be traced to a similar origin. Reconstruction of the evolutionary history of the species indicates that a severe reduction of the geographic range of the species occurred as a result of climatic deterioration during the Late Pleistocene. Although large numbers of populations appear to have become extinct, others survived to give rise to the modern populations of the species that inhabit China today. The two populations showing a high prevalence of premolar agenesis appear to have originated from one that passed through a population bottleneck and suffered the consequences of founder effect in the Late Pleistocene. This interpretation is supported by evidence of dental agenesis in a population of an insectivore species from the same region and by the fact that premolar agenesis is not found in any of the other species ofRhinopithecus. There is no evidence to support the interpretation that dental agenesis inR. roxellana is due to natural selection, mutation or an evolutionary force other than a small population effect.     

Influence des toxines deBacillus thuringiensis sur divers caractères physiologiques de Drosophiles adultes

Summary The effects of culture extracts ofB. thuringiensis Serotype I have been analysed on adult Drosophiles. The thermostable toxin, administered every day, causes a reduction of longevity and fecundity as well as a decrease in the size of the eggs. The various characteristics studied are not sensitive to the toxic effects to the same extent. The method used also made it possible to demonstrate differences in toxicity between the preparations. The signification of these observations is discussed.

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Avec le concours de MlleM. F. Clavel, biologiste adjointe au C.N.R.S.