Which of the following correctly describes the general trend in the evolution of hominid teeth?
On this page... Show Examining the skulls of living apes and our extinct ancestors allows us to explore characteristics which reflect the evolutionary relationships in our family tree. These skulls are all casts of original fossils. The ancestors of today's modern apes (gorillas, orangutans, gibbons, chimpanzees and humans) first appeared in the fossil record about 27 million years ago. By
examining their skulls we can explore characteristics which reflect their evolutionary relationships. Australopithecines: hominins characterized by relatively small brains, large cheek teeth, a skeleton with some ape-like features and little evidence of culture. Cranial capacity: the capacity or size of the brain case and therefore the brain. Dental arcade: the shape made by
the rows of teeth in the upper jaw. Foramen magnum: the great hole in the underside of the skull that forms a passage from the brain cavity to the spinal canal. Homo species: hominins characterised by relatively and absolutely large brains, a modern skeleton, reduced tooth and jaw size and an involvement in cultural activities. Inferred culture: the material evidence that indicates that a species had developed a way of living that was passed on from one generation to another. mya: million years ago unifacial: having one worked side ya: years ago Back to top of main content Go back to top of page journal article Tooth Size and Shape and their Relevance to Studies of Hominid Evolution [and Discussion]Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences Vol. 292, No. 1057, The Emergence of Man (May 8, 1981) , pp. 65-76 (12 pages) Published By: Royal Society https://www.jstor.org/stable/2398644 Read and download Log in through your school or library Read Online Read 100 articles/month free Read Online (Free) relies on page scans, which are not currently available to screen readers. To access this article, please contact JSTOR User Support. We'll provide a PDF copy for your screen reader.With a personal account, you can read up to 100 articles each month for free. Get StartedAlready have an account? Log in Abstract Teeth have the potential to provide evidence about both the patterns of diversity of fossil hominids and the functional adaptations of early hominid taxa. Comparative studies of dental function and the direct examination of wear patterns in fossil teeth are now providing data for testing hypotheses that major differences in dietary adaptations underlie lineage diversity in the early hominids. However, this review focuses on the contributions that dental evidence can make to hominid systematic studies. Attention is drawn to the value of tooth enamel as a morphological marker and the major contribution that teeth make to the hominid fossil sample. Systematic analysis of hominid remains must start with the identification of patterns of morphological variation. Only then can the taxonomic significance of the morphological differences be assessed and attempts made to link designated taxa in a phylogenetic scheme. The preliminary results of a detailed metrical survey of early hominid premolar and molar teeth are presented. As part of this study cusp areas of first mandibular molars were measured by planimetry. Analysis of these data, without any prior assumptions about taxonomic groups, has demonstrated that the major axis of variation separates the pooled sample into morphological subgroups. These methods provide a systematic and rigorous way of identifying patterns of tooth crown morphology and will allow a more objective assessment of the affinities of individual specimens. Fossil taxa are described in terms of both absolute and relative tooth size. If canine base area and molar crown area are considered there is considerable overlap between Australopithecus africanus and Australopithecus (Paranthropus) robustus whereas there is little or no overlap between the ranges of Australopithecus africanus and Australopithecus (Paranthropus) boisei. Differences in relative tooth size among fossil taxa are taken as an example of how to attack the problem of assessing the taxonomic significance of morphological differences. Analogues from modern primates are used to derive tooth-body size relations for three relative growth models. The results suggest that increases in body size are usually accompanied by a more rapid rate of increase in canine size than in molar size. This suggests that the relatively smaller canines of the 'robust' australopithecines are not the result of simple scaling, but represent the result of selection against an allometric trend. Preliminary results of a survey of the subocclusal morphology of fossil teeth are presented to indicate the potential of radiographic studies and to demonstrate that changes in root morphology can be correlated with crown shape and relative size. Publisher Information The Royal Society is a self-governing Fellowship of many of the world's most distinguished scientists drawn from all areas of science, engineering and medicine, and is the oldest scientific academy in continuous existence. The Society’s fundamental purpose, reflected in its founding Charters of the 1660s, is to recognise, promote, and support excellence in science and to encourage the development and use of science for the benefit of humanity. The Society has played a part in some of the most fundamental, significant, and life-changing discoveries in scientific history and Royal Society scientists continue to make outstanding contributions to science in many research areas. Rights & Usage This item is part of a JSTOR Collection. What describes the general trend in hominid evolution?Hominin evolution is characterized by two main trends, transition to bipedality and increase in brain size. Fossil evidence shows that both trends had a major impact on the structure and function of the hominin skull.
Which of the following correctly describes the trend in the evolution of the hominid jaw?Which of the following correctly describes the evolutionistic view of the trend in the evolution of the hominid jaw that took place over millions of years, from early ancestors to modern humans? The jaw became less rectangular and more arched.
Which of the following best describes trends in hominid?Which of the following best describes trends in hominid evolution that took place over millions of years, from early ancestors to modern humans? Their jaw became more parabolic in shape, their gestation period increased, and they evolved to walk upright.
Which of the following trends appeared earliest in hominid evolution?Which of the following trends appeared earliest in hominid evolution? The ability to walk upright on two legs. had to occur for humans to be mobile and eyesight to improve.
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