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At least 19 recordsLinked to original sources
PubMed1978

Middle ear morphology of Lemur variegatus. Some implications for primate paleontology.

The middle ear morphology of Lemur variegatus, a strepsirhine primate, is described. Although no promontory branch of the internal carotid artery appears, there is a well-developed "promontory canal" containing a nerve trunk. This structure, which is previously undescribed in strepsirhines, is made up of the tympanic nerve and the internal carotid nerve. The implications of this discovery for paleontology, systematics, and future research are discussed.

Animals↗
PubMed1979

[Goethe's own testimony about his involvement with "organic Nature." III. Letters (1818-1832)].

This third and last extract from GOETHE's letters between 1818 and 1832 follows the Sophien-Ausgabe of Weimar with the exception of the last two remarks which were drawn from other sources. In 1818, GOETHE riched the 69th year of his life. In this late life-time, he corresponded with scientists, literati, musicians, his son, and his grand-duke CARL AUGUST. The subjects of his correspondence are problems of the scientific investigations' organization as well as of true science, predominantly of paleontology and general morphology including the comparative anatomy.

Anatomy, Comparative↗
PubMed1979

Trends and developments in physical anthropology, 1978-1979.

Members of the American Association of Physical Anthropologists were asked to supply information about their current programs and their own graduate training in order to compile a training directory and to analyze certain aspects of the discipline. The data indicate that the majority consider their graduate training to have been deficient, mainly in statistics, genetics, chemistry, physiology, and mathematics. The areas though most important for future research in physical anthropology include fields such a genetics, anatomy, ecology, physiology, and paleontology, although a great many individuals are engaged in teaching and research in other areas. A brief analysis of relative growth in the field over the last few decades indicates a serious imbalance between the number of new Ph.D.'s and available employment opportunities.

Anthropology, Physical↗
PubMed1979

[The primary structure of the hemoglobin of the greylag goose (Answer anser) and the unequal evolution of the beta-chains (an experimental approach to a biochemical analysis of behaviour (author's transl)].

The primary structures of the alpha- and beta-chains from greylag goose (Anser anser) hemoglobin are given. The sequence was deduced automatically in the sequenator. They differ from chicken alpha-chains in the exchange of 30, from beta-chains in the exchange of only 8 amino acid residues, respectively. The contact points of inositol pentaphosphate with the beta-chains are identical in chicken and greylag goose. Unequal evolution of the beta-chains was found, which is published here for the first time. By comparing the sequences of chicken and greylag goose and considering paleontological data, we found the mutation rate of the alpha-chains to be normal, i.e. 6 million years/mutation. This corresponds to the values for other species. The mutation rate of beta-chains is reduced and was calculated at 25 million years/mutation. This is possibly due to a specific function of beta-chains. This paper is the basis of our attempt to explain on a molecular basis the ability of bar-headed goose (Anser indicus) to fly and breathe at high altitudes.

Altitude↗
PubMed1977

Morphometrics of the Neandertal talus.

A number of morphometric analyses of Neandertal tali since the turn of the century have failed to reach a consensus on the functional affinities of these fossil foot bones. To clarify the problem a univariate and multivariate analysis of the available Neandertal and Skhūl tali in relation to those of modern humans was performed using nine linear dimensions and four angles. Our analysis indicates that Neandertal tali are indistinguishable from modern human tali in the implied locomotor capabilities and similar in overall size and proportions. The primary differences between the fossil and modern tali involve the greater articular robustness of the fossils, probably to compensate for higher levels of biomechanical stress.

Anthropometry↗
PubMed1977

A gracile hominid cranium from upper member G of the Shungura formation, Ethiopia.

A fragmentary hominid cranium with teeth, specimen L.894-1, dating from 1.84 m.y. BP in the Shungura Formation at Omo, is described. From its dental and cranial morphology and because of similarities to Olduvai Hominids 24 and 13 and Sangiran 4, among others, it is concluded that the specimen represents a member of an early species of the genus Homo (Homo habilis or Homo modjokertensis). The specimen shows approximal grooving on the premolars, pre-mortem chipping of the molar enamel, foramina ovale and spinosum divided by the sphenosquamosal suture, limited pneumatization of the mastoid region, and a possible interparietal bone. Sedimentological, ostracod, pollen, macrofloral, and taphonomic data indicate that the paleo-environmental context was a savanna/grassland or savanna woodland on the margin of a saline lake.

Cephalometry↗
PubMed1977

New fossil hominids from Laetolil, Tanzania.

New fossil hominid specimens from the Laetolili fossil locality in Tanzania are described. The material includes mandibles and teeth derived from reliably-dated deposits of Pliocene age. Preliminary descriptions, measurements and illustrations are presented.

Dentition↗
PubMed1977

Some notes on the Vértesszöllös occipital.

An examination of the Vértesszöllös occipital bone indicates the need for takings its condition and preservation as well as certain aspects of its morphology into account prior to a metric assessment of its features. This analysis confirms the presence of extrasutural bones on the lambdoidal suture as well as some distortion in the sagittal curvature of this region. The advisability of using the endocranial sutures as well as other data for defining lambda in cases such as this is discussed, and a procedure for determining the position of opisthion is indicated. A metric and morphological analysis is used to support the claim that the specimen can be considered a large late representative of Homo erectus in Europe.

Cephalometry↗
PubMed1978

Mineral analysis of ancient Peruvian hair.

Ancient Peruvian hair has been excavated from a series of archaeological sites on the Peruvian coast. After careful cleaning, examination by scanning electron microscopy revealed most of the samples to be in a state of preservation comparable to modern hair. No evidence of pathological conditions was observed. Trace metal composition was determined by atomic absorption and flame emission spectrophotometry and nitrogen by Kjeldahl analysis, producing the following results: (1) nitrogen is lost with time, while all other tested minerals except zinc and copper showed irregular increases; (2) relatively high chromium levels may indicate that diabetes was not present in the samples; and (3) no consistent trend in the ratio of calcium to strontium was found through time and across corresponding dietary shifts.

Adolescent↗
PubMed1978

Florisbad and human population succession in Southern Africa.

The human cranium recovered at Florisbad in 1932 is compared with other Sub-Saharan African hominid remains from Broken Hill, the Omo and Klasies River Mouth. The Florisbad frontal is very broad, but despite this breadth and differences in zygomatic form, there is a definite resemblance to archaic Homo sapiens from Broken Hill. There is also some similarity to both Omo I and Omo II, while fragmentary remains from Klasies River are more lightly built and hence more modern in appearance. These impressions are strengthened by measurement and statistical analysis, which demonstrates that Florisbad and Broken Hill are distant from recent African populations. Even if Florisbad is less archaic than the earlier (Middle Pleistocene?) hominid, it is not noticeably Bushman-like. New dates suggestive of early Upper Pleistocene antiquity also place Florisbad securely in a lineage containing Broken Hill, and there is no evidence to support special ties with any one group of living Africans.

Biological Evolution↗
PubMed1978

Evolutionary significance of the mandibular foramen area in Neandertals.

An unusual morphology of the mandibular foramen area is described, and its incidence determined for several fossil and modern hominid skeletal samples. This morphology, designated the horizontal-oval type mandibular foramen, is found in 46.2% of the 26 Neandertal foramina examined and in 23.1% of a European Upper Paleolithic sample of 13 foramina. In a total of 747 foramina from five modern skeletal samples, the highest incidence is 3.72%. Possible explanations for the presence of the H-0 trait and its unusually high incidence in Neandertals are examined. It is concluded that this feature is probably a genetic trait which either (1) might be selected for in Neandertals as a part of a massive masticatory apparatus, or (2) represents a discrete cranial trait without functional significance that simply reflects the high incidence of certain genes in Neandertal gene pools.

Biological Evolution↗
PubMed1978

The vermiculate surface pattern of brow ridges in Neandertal and modern crania.

A convoluted surface pattern of ridges and grooves characterizes the frontal torus in adult Neandertal fossils. Modern human skulls rarely have the pattern well developed. It is not observed in postcranial bones, nor in skulls of Neandertal children. This vermiculate bone is resistant to oriented cracking from weathering or fractures. Structural characteristics of the bone give evidence on the problem of the function of hominid brow ridges.

Cephalometry↗
PubMed1978

Fore- and hindlimb proportions in Plio-Pleistocene hominids.

Associated fore- and hindlimb parts of five individuals are known from the hominid Plio-Pleistocene fossil collections in Africa. Four of these have been classified as Australopithecus and show definite evidence that in comparison with humans, forelimbs were relatively large and hindlimbs were relatively small. The fourth individual, placed in the genus Homo, has human proportions. These findings do not necessarily imply locomotor differences: the forelimbs may have been relatively long in Australopithecus simply because they were as yet not completely reduced from their generalized hominoid ancestral state.

Animals↗
PubMed1978

The functional significance of the squamosal suture in Australopithecus boisei.

A juvenile Australopithecus boisei specimen from the Omo basin, southern Ethiopia, is found to exhibit and extraordinarily large overlap of the temporal squama on the parietal, a phenomenon shared with at least two adult specimens of A. boisei. An attempt is made to interpret the overlap as a structural (bony/ligamentous) adaptation necessitated by the unique combination of certain components of the masticatory system of A. boisei. These are: (1) the massiveness and strength of the temporalis muscle, (2) its relatively anterior location, and (3) the lateral position of the masseter muscle due to the flaring of the zygomatic arches. The effect of the temporalis muscle is to create excessive pressure on the portion of the squamosal suture along the parietal, while the lateral placement of the masseter and the resultant increase of pressure on the temporal squama via the zygomatic arch tend to "loosen" the contact between the temporal and parietal bones.

Animals↗
PubMed1978

Micropithecus clarki, a small ape from the Miocene of Uganda.

Micropithecus clarki, from Miocene sediments of Napak, Uganda, is the smallest known hominoid primate, living or fossil. In facial morphology it is very similar to extant gibbons. Dentally, it is most similar to the small apes from the Miocene of Kenya, Dendropithecus and Limnopithecus. All of the apes from the early Miocene of East Africa seem to represent a single phyletic group that could be easily derived from the Oligocene apes known from the Fayum of Egypt. Pliopithecus from the Miocene of Europe is more closely allied with the Oligocene radiation than with the later East African radiation.

Animals↗
PubMed1978

The femur in early human evolution.

Uni- and multivariate analyses of 5 fossil and 215 extant hominoid femora show that two morphological patterns of hominid femora existed about two million years ago. Femora classified as Homo sp. indet. (KNMER 1472 and 1481) are more like Homo sapiens although not identical. Those classified as Australopithecus robustus (SK 82 and 97) and A. boisei (KNM-ER 1503) are similar to one another but uniquely different from any living hominoid. The strong mophological constrasts imply biomechanical and possible locomotor differences, although these are as yet unknown.

Animals↗
PubMed1979

Computed tomography and biomechanical analysis of fossil long bones.

Computerized transverse axial scanning (computed tomography) is a relatively new radiographic technique designed to recover precise cross-sectional images (tomograms) of 3-dimensional objects. This highly sensitive process permits tissues of similar density to be separated and displayed unambiguously. These special features are, therefore, ideal for analyzing the cross-sectional geometry of intact fossil long bones, even when they are highly mineralized and their medullary cavities are occluded by matrix. In order to demonstrate the utility of this method in assessing the complex relationship between fossil structure and probable function, geometrical and biomechanical properties of midshaft tomograms of femora and tibiae have been analyzed for a comparative primate sample consisting of Megaladapis edwardsi (an extinct giant prosimian from Madagascar), Indri indri (the largest extant prosimian), and Homo sapiens.

Animals↗