Showing papers by "Robert S. Corruccini published in 1978"
TL;DR: It is concluded that dwarfism is an adaptive process which is probably the result of a density-dependent factor(s) (i.e. a resource limited system) and a pattern of dwarfing allometry is broadly similar to within-species allometry, and is quite dissimilar to synchronous interspecific allometry.
Abstract: Evolutionary "dwarfism" or "nanism" is the phenomenon in which a significant de- crease in mean body size of a lineage (an ancestral-descendant sequence of populations) occurs through time. A detailed analysis of several Late Quaternary dwarfed marsupial lineages from Australia is given. Based on linear tooth dimensions of the dwarfed lineages, four points are considered: 1) percent dwarfing; 2) evolutionary rates of change of tooth dimensions; 3) varia- tion within lineages before and after dwarfing; and 4) several aspects of multivariate dental allometry. (The lineages include Macropus titan (fossil)-M. giganteus (Recent) and Osphranter cooperi (fossil)-O. robustus (Recent) in the family Macropodidae (kangaroos), and Sarcophilus laniarius (fossil)-S. harrisii (Recent) in the family Dasyuridae (Tasmanian- devil).) Dental measurements led to these conclusions: 1) Species with the largest body size show the greatest size reduction, and the species with the smallest body size change the least. 2) Evo- lutionary rates for this reduction in Australian lineages are similar to comparable Post- Pleistocene dwarfed lineages in Europe. 3) Tooth width, especially posterior width, changes more rapidly than length. The first molar changes relatively slowly, especially in length. 4) Variability is higher in the dwarfed forms than in the larger ancestors. 5) Multivariate allometric rates of dwarfing are consistent with results for rates of change calculated in darwins for the relation between change in length and maximum width (and less so for the relation between Ml and M4 reduction). This pattern of dwarfing allometry is broadly similar to within-species allometry, and is quite dissimilar to synchronous interspecific allometry. Brief consideration is also given to taxonomy of dwarfing lineages and to problems of concur- rent megafaunal extinctions. It is concluded that dwarfism is an adaptive process which is probably the result of a density-dependent factor(s) (i.e. a resource limited system).
103 citations
TL;DR: Morphometric data on the wrist joints of hominoid taxa have been compared and man is relatively similar to African apes in this factor while Asian apes are at the opposite extreme; cercopithecoids appear to be roughly intermediate.
77 citations
TL;DR: A cross-primate survey of dental scaling relative to skull (and inferred body) size is given in this study, using a principal component technique to measure the multivariate growth relation between two sets of data: dental size and cranial size.
Abstract: Disagreement is current over the question of whether relatively large teeth in some large primates are a natural outcome of growth trends instead of an indication of intrinsic differences. A cross-primate survey of dental scaling relative to skull (and inferred body) size is given in this study, using a principal component technique to measure the multivariate growth relation between two sets of data: dental size and cranial size. Cheek teeth are strongly positively allometric in restriced taxonomic groups, especially in cercopithecoids. Conversely, the allometry drops to an almost linear proportional growth relation when variation in diet is controlled.
43 citations
TL;DR: This study is based upon 48 3-dimensional coordinates taken on 4 fossil hominid and 127 extant hominoid coxal bones and shows a high degree of agreement between the methods.
Abstract: This study is based upon 48 3-dimensional coordinates taken on 4 fossil hominid and 127 extant hominoid coxal bones. The follis include Sts 14, SK 3155, MLD 7, and MLD 25. The comparative sample consists of 42 Homo sapiens, 27 Pan troglodytes, 29 Gorilla gorilla and 29 Pongo pygmaeus. The coordinates improve the metrical representation of the bone beyond what can be done with linear measurements because the shape complexity of the os coxae is so great. The coordinates are rotated and translated so that all bones are in a standard position. The coordinates are then standardized for each specimen by dividing all coordinates by the pooled standard deviation of X, Y, and Z coordinates. These data are treated to standard statistical analyses including analysis of variance, Penrose size and shape statistics, principal coordinates and components, and canonical variates analysis. The data are then further altered by using some specimen as a standard and rotating each specimen until the total squared distance between its coordinates and those of the standard are minimized. The same statistics are applied to these "best fit" data. The results show a high degree of agreement between the methods. The hominid os coxae are dundamentally different from the other hominoids and the fossil hominids share the basic hominid configuration but with some unique differences.
28 citations
TL;DR: Compared to the conventional measures of maximum dental length and breadth, the new measurements were a better source of taxonomic discrimination.
24 citations
TL;DR: The results do not support biomechanical assumptions of strongly positive allometry of the femur head, which have been used to argue that the australopithecine hip joint was not relatively small.
Abstract: Relative growth of the human femur head is studied by a logarithmic principal components method. Growth rates differ according to the population sampled and the other body dimensions being compared, and especially according to sex. The results do not support biomechanical assumptions of strongly positive allometry of the femur head, which have been used to argue that the australopithecine hip joint was not relatively small.
19 citations
TL;DR: A metrical test supports the view that hominoid distinctions are monophyletic in origin and the primates that are behaviorally and functionally convergent on hominoids are only partially convergent or not convergent in shoulder morphology.
Abstract: A morphocline in the organization of the shoulder joint is demonstrated among anthropoid primates. This metrical test supports the view that hominoid distinctions are monophyletic in origin. The primates that are behaviorally and functionally convergent on hominoids are only partially convergent or are not convergent in shoulder morphology.
18 citations
TL;DR: Hinoid morphology and proportions are seen as having developed from parallel increase in body size and necessarily associated allometry, suggesting that more than one kind of locomotor pattern could have given rise to their distinctive shape.
Abstract: Since the time of Darwin and Huxley, it has been a common opinion that extant hominoids (apes and man) are unified by a manner of locomotion and posture, and associated derived functional morphology, indicating a closely related and distinct group. Haeckel (1868), Keith (1923) and Gregory (1928) early documented the body proportion synapomorphies supporting the monophyly of hominoids. Schultz (e.g., 1950; 1963) provided large amounts of confirmatory data. Simons (1972), Simons and Pilbeam (1965), Simons and Fleagle (1973), Pilbeam (1969), Conroy and Fleagle (1972) and Zwell and Conroy (1973) have spread the idea that long-term parallelism is the cause of hominoid similarities. More recently, the hypothesis of hominoid parallel evolution has been proposed more rigorously in terms of allometry-the differential growth of body segments. Thus, hominoid morphology and proportions are seen as having developed from parallel increase in body size and necessarily associated allometry, suggesting that more than one kind of locomotor pattern could have given rise to their distinctive shape. Three specific hypotheses have been proposed in this regard. Biegert and Maurer (1972) show that arm length, and less markedly leg length, is positively allometric among cercopithecoid (Old World) monkeys and that some hominoids lie on the regression line extrapolated from the monkey sample indicating "generalized proportions" in a larger size range. Their regressions are of skeletal segment length ratios versus a vertebral measure of trunk
17 citations
TL;DR: Multivariate shape analysis of 15 palato-facial measurements of the RusingaD.
Abstract: Multivariate shape analysis of 15 palato-facial measurements of the RusingaD. africanus and MorotoD. major specimens in comparison with apes and monkeys fails to support the hypothesis of special relationship between the dryopithecine species and extant African pongids. TheD. africanus shares with gibbons and cercopithecoids the primitive catarrhine metrical pattern, while chimpanzees and gorillas show a different, derived pattern. TheD. major shows partial convergence on the shape pattern typifying gorillas.
7 citations