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Primate Taxa (primate + taxa)

Distribution by Scientific Domains

Life Sciences	80%

Selected Abstracts

Rarity, specialization and extinction in primates

JOURNAL OF BIOGEOGRAPHY, Issue 4 2002
A. H. Harcourt
Aim To determine and explain biological traits that distinguish rare from common primate taxa. Location Africa, Americas, Asia, Madagascar. Methods We compare the biology of rare primate taxa with the biology of common taxa. Rarity is defined by (1) small size of geographic range; (2) small geographic range plus low local population density; and (3) small geographic range plus low local density plus narrow habitat specificity. After a linear comparison of size of geographic range with various biological traits, globally and by realm, extremes of rarity and commonness per realm are identified, and then combined for a global analysis. Tests are done both with genera treated as independent data points (n=62), and also with phylogenetic control by use of an independent contrasts test. Extinction risk in vertebrates, including primates, often correlates with high resource requirements, slow population recovery rate, and specialization. The three indices of rarity are therefore compared with these three general traits. Measures of resource use are body mass, local density, annual range size, and group size; of recovery rate, interbirth interval, and maximum intrinsic rate of natural population increase; and of degree of specialization, variety of diet, of habitats, maximum latitude, and morphological variety. All data come from the literature. Because several measures are compared, probabilities are Bonferroni corrected. Results If rarity in primates correlates with any biological attribute, it consistently correlates with only measures of specialization, and not with measures of high resource use, or slow population recovery rate. Without phylogenetic correction, the first two indices of rarity associate significantly with all four measures of specialization, and the third with maximum latitude. With phylogenetic correction, the first index still associates with all four, the second with two (maximum latitude, number of species per genus), and the third shows no significant associations. While the four measures of specialization are strongly interrelated, stepwise regressions on geographic range indicate that maximum latitude has the strongest effect, followed by dietary variety and number of species per genus and, finally, habitat variety. Main conclusions The most commonly demonstrated traits of susceptibility to extinction are those of high resource use, slow recovery rate, and specialization. Yet, while rarity (almost however, it is defined) is an inevitable precursor to extinction, specialization is the only trait found to correlate with rarity in this study. We cannot explain this apparent contradiction. [source]

Technical note: Forearm pronation efficiency analysis in skeletal remains

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 3 2009
Ignasi Galtés
Abstract This work presents an original methodology for analyzing forearm-pronation efficiency from skeletal remains and its variation with regard to changes in the elbow position. The methodology is based on a biomechanical model that defines rotational efficiency as a mathematical function expressing a geometrical relationship between the origin and insertion of the pronator teres. The methodology uses humeral distal epiphysis photography, from which the geometrical parameters for the efficiency calculus can be obtained. Rotational efficiency is analyzed in a human specimen and in a living nonhuman hominoid (Symphalangus syndactylus) for a full elbow extension (180°) and an intermediate elbow position (90°). In both specimens, the results show that this rotational-efficiency parameter varies throughout the entire rotational range and show a dependency on the elbow joint position. The rotational efficiency of the siamang's pronator teres is less affected by flexion of the forearm than that of the human. The fact that forearm-pronation efficiency can be inferred, even quantified, allows us to interpret more precisely the functional and evolutionary significance of upper-limb skeletal design in extant and fossil primate taxa. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc. [source]

Primate communities: Past, present, and possible future

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue S39 2004
Kaye E. Reed
Abstract An understanding of the fundamental causes of the structure of primate communities is important for studies of primate evolutionary history, primate behavioral ecology, and development of conservation strategies. Research into these structuring factors has benefited from new perspectives such as consideration of primate phylogenetic history, metacommunities, and interactions with predators and nonprimate competitors. This review presents the underlying factors of primate community structure within the biogeographic regions of Madagascar, the Neotropics, Africa, and Asia. One of the major differences among these locations likely resulted from the initial primate taxa that colonized each region (a single colonization event in the case of Madagascar and South America, and multiple radiations of higher-level taxa in Africa and Asia). As most primates live in forests, the differences among the forests in these locations, caused by various climatic influences, further influenced speciation and the development of primate communities. Within these habitats, species interactions with different groups of organisms were also instrumental in developing community dynamics. Through an investigation of these fundamental factors, we identify some of the most important effects on primate communities in each region. These findings suggest that low primate richness in Asia may be caused by either the abundance of dipterocarp trees or high levels of monsoon rains. High numbers of frugivores and a lack of folivores in neotropical communities may be associated with competiton with sloths that were already present at the time of initial radiation. Climatic patterns which affect forest structure and productivity in Madagascar may be responsible for high numbers of folivorous lemurs. The identification of these factors are important for the conservation of existing primate communities, and indicate directions for future studies. Yrbk Phys Anthropol 47:2,39, 2004. © 2004 Wiley-Liss, Inc. [source]

Chronology of primate discoveries in Myanmar: Influences on the anthropoid origins debate

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue S35 2002
Russell L. Ciochon
Abstract The history of primate paleontology in Asia is long and complex, beginning with the first discoveries of fossil primates on the Indian subcontinent in the early 1830s. The first Eocene mammals from Asia were collected in Myanmar and described in 1916, while the first primates, Pondaungia and Amphipithecus, were described in 1927 and 1937, respectively, both from the Pondaung Formation in Myanmar. For the next 60 years, these two Pondaung taxa remained as the only known Eocene primates from Myanmar and one of the few records of Eocene primates from all of Asia. Taxonomically, Pondaungia and Amphipithecus were linked with a number of different groups, including archaic, hoofed ungulates (condylarths), adapiform primates, omomyid primates, and anthropoids. While no consensus existed, Pondaungia and Amphipithecus were most commonly compared with anthropoids. Beginning in the late 1990s, new primates were discovered in Myanmar, including smaller-bodied forms such as Bahinia and Myanmarpithecus. Also, new and better specimens of the larger-bodied Pondaungia and Amphipithecus began to appear, including the first cranial and postcranial fragments. Evaluations based on these new specimens, especially the postcrania, indicate that the two larger-bodied Myanmar taxa are adapiform primates that show their closest affinities to North American notharctines. The smaller-bodied taxa remain enigmatic, but may share their closest affinities with North American and Asian omomyid primates and Asian Tarsius. None of the known Asian primate taxa appear closely related to African anthropoids, which suggests that true anthropoids did not reach Asia until the latest Oligocene or earliest Miocene. These facts make an Asian origin for Anthropoidea unlikely. Additional and earlier evidence from both Asia and Africa is required before the ultimate origin of anthropoids can be determined. It appears possible that true anthropoids were an ancient radiation that may have been part of a Gondwanan (southern hemisphere) community that is, at present, poorly sampled and little understood. Yrbk Phys Anthropol 45:2,35, 2002. © 2002 Wiley-Liss, Inc. [source]

Dental topography and diets of four old world monkey species

AMERICAN JOURNAL OF PRIMATOLOGY, Issue 6 2009
Jonathan M. Bunn
Abstract Dental topographic analysis allows comparisons of variably worn teeth within and between species to infer relationships between dental form and diet in living primates, with implications for reconstructing feeding adaptations of fossil forms. Although analyses to date have been limited mainly to the M2s of a few primate taxa, these suggest that dental topographic analysis holds considerable promise. Still, larger samples including a greater range of species and different tooth types are needed to determine the potential of this approach. Here we examine dental topography of molar teeth of Cercocebus torquatus (n=48), Cercopithecus campbelli (n=50), Colobus polykomos (n=50), and Procolobus badius (n=50). This is the first such study of large samples of Old World monkeys, and the first to include analyses of both M1s and M2s. Average slope, relief, and surface angularity were computed and compared among tooth types, wear stages, and species. Results suggest that (1) data for M1s and M2s cannot be compared directly; (2) slope and relief decline with wear on M2s of all taxa, and M1s of the colobines, whereas angularity does not generally change except in the most worn specimens; and (3) folivorous colobines tend to have more sloping surfaces and more relief than do frugivorous cercopithecines, though angularity does not clearly separate taxa by diet. Am. J. Primatol. 71:466,477, 2009. © 2009 Wiley-Liss, Inc. [source]