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At least 883 records · Page 49Linked to original sources
PubMed2004

Barking up the wrong ape--australopiths and the quest for chimpanzee characters in hominid fossils.

With the shift during the 1980s from a human-great ape ultimately to an orangutan-(gorilla-(human-chimp)) theory of relatedness, the search for chimpanzee-like features in early hominids intensified. Reconstructions of early hominids became caricatures of chimpanzees, not only in soft tissue features (e.g. the nasal region), but in supposed bony structures (e.g. an anteriorly and especially superiorly protruding a supraorbital torus with a distinct posttoral sulcus behind). In spite of rampant >>Panophilia,<< actual morphologies of the majority of early hominid specimens are those cited as uniting an orangutan clade. Those specimens that are >>chimpanzee-like<< are probably not cladistically hominid.

Africa↗
PubMed2005

The fossil fallacy.

Explore the source record for details and available documents.

Biological Evolution↗
PubMed1991

X-ray microanalysis of fossil dinosaur bone: age differences in lead, iron, and magnesium content.

Bones of dinosaurs, Gallimimus bullatus, belonging to selected age groups, were studied using an X-ray microanalyser. The content of lead, iron, and magnesium, as well as the distribution of those elements in the investigated bone areas were determined. The results showed, that bones of old animals contained the highest level of lead and iron, whereas in young dinosaurs the respective values were lowest. The obtained data were compared with the results of X-ray microanalysis of the contemporary bone.

Aging↗
PubMed1991

Intraspecific variation and sexual dimorphism in cranial and dental variables among higher primates and their bearing on the hominid fossil record.

The extent and nature of dental and cranial sexual dimorphisms in extant hominoids have been investigated using reliably sexed samples of Homo sapiens (n = 75), Pan troglodytes (n = 51), Gorilla gorilla (n = 64) and Pongo pygmaeus (n = 43). Seventy nine measurements (35 dental, 16 mandibular and 28 cranial) formed the basis of the study. The patterns of mean differences and dispersions between the taxa were compared across the anatomical regions and the group structures of the separate sex samples were analysed using multivariate (PCA and CVA) analysis. Within and between group variations were compared across the taxa to investigate whether any variables were consistently effective sex or taxonomic discriminators. The study confirmed that there were differences in degree and pattern of sexual dimorphism between the extant higher primates, but the results did not substantiate the distribution of patterns as suggested by Oxnard et al. (1985); in particular there was no evidence of the dispersion differences noted by those authors. There were sufficient consistencies in the behaviour of variables across the four taxa to suggest that all canine dimensions, postcanine crown buccolingual dimensions and mandibular and cranial breadths are generally good sex discriminators, whereas some incisor dimensions, postcanine crown mesiodistal dimensions and facial heights are more effective at discriminating between the four extant taxa included in this study.

Animals↗
PubMed1991

Porotic hyperostosis on fossil skulls. A study, using scanning electron microscopy.

Fine structural alterations of cancellous bone in all three forms of porotic hyperostosis (porotic, cribrotic, and trabecular) were examined by the authors. The architecture of cancellous bone was altered, resulting in extended and dilated medullary spaces. Single-bone trabeculae, too, differed from normal by alteration of internal collagen structure and lamellae.

Fossils↗
PubMed1990

Morphological variation in the nasal region of extant and fossil hominids.

We describe here the mid-facial region of a skull of anatomically modern Homo sapiens (FAI 3/2/1) that exhibits upwardly divergent nasal bones. In previous literature, that pattern has been described as a diagnostic character state for the robust early hominid taxon Paranthropus. This specimen supports our viewpoint that nasal region morphology varies extensively within and between living hominoid primate taxa, in patterns that provide a basis for understanding how microevolutionary variation serves as the basis for macroevolutionary transformations.

Animals↗
PubMed1987

Replication technique for studying microstructure in fossil enamel.

The present paper describes a two stage impression technique using a silicone elastomer suitable for field replication studies; which requires high dimensional stability, defined resolution, and being capable of reproducing inaccessible details. A test object consisting of etched pearlite possessed fine detail [greater than 1 micron to less than 0.1 micron] which was suitable for testing negative/positive replica combinations. Coltene President light-body impression material was capable of resolving parallel side depressions of widths greater than or equal to 0.2 micron, and it possesses very good dimensional stability with time, allowing the production of positive casts to be deferred for several months. Low viscosity Spurr resin reproduced this detail, and flowed into inaccessible sites. Although there was evidence of bulk contraction on curing, there was no significant shrinkage on flat [linear] surfaces or in vertical relief dimensions. Replicas of fractured hominid teeth showed good surface detail, and reproduction of inaccessible three-dimensional features on enamel surfaces. Enamel prism shape was pattern 3.

Animals↗