摘要:

Following the studies on Nycticebus coucang, Lemur catta and Tupaia glis, the Visual Discrimination Learning Set was tested on the nocturnal prosimian thick-tailed bush babies (Galago crassicaudatus). Their performance occupied a position between that of Lemur and Tupaia, and was almost the same as that of Nycticebus. The hypothesis behavior analysis was made on the performance of the 4 species. The species differences in performance showed a strong relationship with the degree of neocortex development and eco-ethological characteristics.

ISSN:0015-5713    

DOI:10.1159/000156282

出版商:S. Karger AG    

年代:1987

数据来源: Karger

摘要:

Allometric scaling relationships between body weight, bone length, and cross-sectional dimensions of the lower limb bones which measure structural strength and rigidity (area, second moments of area) are investigated in Homo, Gorilla, Pan, Pongo, and Macaca. Cross-sectional dimensions are slightly positively allometric and highly correlated with body weight; within-bone proportional differences are largely a result of differences in relative bone length to body weight. Orangutans show the greatest deviation from general scaling relationships between lower limb bone structural strength and weight, probably due to habitual upper limb suspension. Formulas for the prediction of weight from cross-sectional dimensions are presented.

ISSN:0015-5713    

DOI:10.1159/000156283

出版商:S. Karger AG    

年代:1987

数据来源: Karger

摘要:

A new subspecies of Hapalemur griseus has been discovered in the area of Fort-Dauphin, Madagascar. It is proposed to name it H.g. meridionalis. The animals resemble the other gentle lemurs except that they are slightly bigger. Chromosomal study shows that their karyotype differs from those of the other gentle lemurs, and a comparison permits the construction of a phylogenetic tree for the genus Hapalemur. Thus, this new subspecies is characterized by its morphology, its karyology and its geographical distribution.

ISSN:0015-5713    

DOI:10.1159/000156284

出版商:S. Karger AG    

年代:1987

数据来源: Karger

摘要:

A comparison of the 44-chromosome gibbons (27 animals from the taxa H. agilis, H. lar, H. klossii, H. muelleri, H. moloch and H. pileatus) shows that these species have a nearly identical, if not identical, G-banding pattern. Two chromosomes, No. 8 and the marker chromosome bearing the nucleolar organizing region, show intraspecific polymorphism. There are three forms of chromosome 8 (8a, 8b, 8c). Chromosome 8a can be derived from 8b by a single pericentric inversion while to derive chromosome 8c from 8b requires at least two pericentric inversions. Apparently, the 44-chromosome gibbons are chromosomally conservative or have only recently differentiated. The presence of a polymorphism of chromosome 8 in four of the six taxa studied in wild-caught animals makes it likely that this polymorphism occurs in natural populations and was the ancestral condition for all the taxa studied. However, the possible existence of natural karyomorphs has conservation implications because animals heterozygous for different forms of chromosome 8 may have lowered fertility due to the production of unbalanced gametes. The exact implications of these chromosomal polymorphisms could be further clarified by a population level study of animals of known provenance.

ISSN:0015-5713    

DOI:10.1159/000156285

出版商:S. Karger AG    

年代:1987

数据来源: Karger

摘要:

New platyrrhine fossils have been recovered from early Miocene deposits near the Pinturas River in Santa Cruz Province, Argentina. Soriacebus ameghinorum is a saki-sized monkey with a deep V-shaped mandible, large procumbent incisors and small marmoset-like cheek teeth. Several other primate taxa are represented by dental, cranial, and post-cranial remains from the same deposits. These fossils document the presence of a phyletically and adaptively diverse fauna of primates in southernmost Argentina during the early Miocene.

ISSN:0015-5713    

DOI:10.1159/000156286

出版商:S. Karger AG    

年代:1987

数据来源: Karger

摘要:

The habitat and plant feeding of 64 well-habituated, individually identified adult male and female yellow baboons was studied for 5 years at Mikumi National Park, Tanzania. Variation across the years showed that a study of only one or two years would have been incomplete and misleading. The list of baboon food species obtained from Mikumi is considerably larger and more diverse than any previously reported. One to six plant parts were eaten from each of more than 180 species. The 25 most common tree genera all contained species used for food. Of the 50 most common grass, shrub and herb genera, 93% included plant foods. Using months in which a species was eaten during at least one year of the study, 21 staple species were eaten during a mean of 8.86 months and 7 were eaten in all 12 months. Although many foods were from commonly available plant species, 15 such species were only rarely eaten. The number of parts of a species eaten per month and an estimate of the amounts eaten per month both varied with temperature and rainfall, being lowest near the end of the cool, dry season. There were substantial differences from year to year in the timing and amount of food production of many species; nevertheless, the same broad feeding pattern was repeated in each of the 5 years of the study. Despite yearly variation in food availability, 14 or more staples and other common foods were eaten in any given month. If crops of many of these foods were to fail, a large number of less commonly eaten species could be substituted. Baboons are eclectic feeders that appear to be optimizing their diet by selective feeding from among a wide array of available foods in an ever-changing floristic environment.

ISSN:0015-5713    

DOI:10.1159/000156287

出版商:S. Karger AG    

年代:1987

数据来源: Karger