摘要:

Comparison of the dental morphology of the Middle Paleocene paromomyid primate Plesiolestes problematicus with that of the Early Eocene microsyopid Cynodontomys latidens indicates that Plesiolestes and Cynodontomys are closely related and that the Microsyopidae are derived from paromomyid primates. The Microsyopidae are, therefore, considered to be primates also. The diagnostic primate molar morphology apparently evolved before the petrosal bulla characteristic of most primates was acquired. Evidence presented here supports a derivation of Primates from leptictid insectivores.

ISSN:0015-5713    

DOI:10.1159/000155511

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

Analysis of brain-body size relationships in australopithecines based on the regression equation y (brain weight) = b·x (body weight)0·23 indicates that graeile and robust australopithecines were equally advanced in the degree of encephalization and clearly above the pongid level of brain evolutio

ISSN:0015-5713    

DOI:10.1159/000155512

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

The premaxillary-frontal articulation has been reported as a common feature in Old World monkeys, while the absence of this contact has been described in bone New World monkeys. In the present study, it was observed in only 2 of 551 Old World monkey skulls and was never found in the New World specimens. The nasomaxillary bone described by Ashley-Montagu in 1935 was absent in all monkeys studied. The premaxillary-frontal articulation is shown to have limited taxonomic value in separating Old and New World monkeys.

ISSN:0015-5713    

DOI:10.1159/000155513

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

The finding of elevated plasma gonadotropin concentrations in an intact rhesus monkey led to the discovery of an X-O chromosomal anomaly. The monkey had skeletal, endocrine, and ovarian histologic characteristics closely resembling those described in human phenotypic females with an X-O karyotype (Turner’s syndrome

ISSN:0015-5713    

DOI:10.1159/000155514

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

Chromosomal evolution was examined in a long-term cell culture derived from Macaca mulatta eye tissue. In addition to the ‘marked’ chromosome that characterizes the rhesus karyotype, other chromosomes that may have originated from it by inversions and translocations were identified at each subculture sampled. Our observations do not warrant the conclusion that all the achromatically distinguished chromosomes observed were ‘marked’ rather than ‘marker’ chromosomes; some, however, resembled the ‘marked’ chromosomes found in Aotus and Ce

ISSN:0015-5713    

DOI:10.1159/000155515

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

No differences in social behavior during the first year of life were found in comparisons of two quadrats of each macaque type when controlling for adult-related differences by rearing infants with one another. No support was found for reports of feral stumptails being more affiliative or less assertive. Another group of rhesus tested in a larger enclosure were more assertive and more fearful when compared with rhesus in a small test cage.

ISSN:0015-5713    

DOI:10.1159/000155516

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

The relation between the reproductive cycles of Presbytis senex and P. s. monticola and environmental factors were studied in two climatically different areas of Ceylon: Polonnaruwa and Horton Plains, respectively. At Polonnaruwa, which is a seasonally dry area, the peak mating period coincided with the period of high rainfall, food abundance, decreasing temperatures and day length, giving rise to a birth peak during the dry season. The gestation period of P. s. senex was estimated, and intratroop breeding synchrony was noted within troops that underwent replacement of the leader male. At Horton Plains, where climatic variations were less marked, a distinct birth peak was not found. The attenuated peaks seemed to be due to intratroop breeding synchrony within established troops. The interbirth interval was 16-17 months, whereas at Polonnaruwa, it was extended to about 24 months.

ISSN:0015-5713    

DOI:10.1159/000155517

出版商:S. Karger AG    

年代:1973

数据来源: Karger

摘要:

Rank order hierarchy was evaluated in four adult female squirrel monkeys in a variety of situations. Dominance relationships were first determined for pairs of monkeys before and after deafening the subordinate monkey. Three of the four monkeys were deafened in this manner. Deafening had no apparent permanent effect on social behavior. The four monkeys were then observed as a group in a large cage, isolated from all other monkeys. The frequency distributions of food stealing, body grasping, and sexual behaviors were consistent with a linear rank order interpretation. For some behavioral units dyadic relationships between monkeys were found to be more reliable predicators of linear hierarchy than frequency distribution. Homosexual encounters appeared to resemble the heterosexual pattern. Linear hierarchy has been observed by others in adult male squirrel monkey groups but not among subadult females.

ISSN:0015-5713    

DOI:10.1159/000155519

出版商:S. Karger AG    

年代:1973

数据来源: Karger