A case of syndactyly in the white-lipped tamarin Saguinus nigricollis.

A case of syndactyly in a captive bred white-lipped tamarin (Saguinus nigricollis) is reported which involved the fusion of metacarpals 3 and 4 of both hands. Variations in the vertebral formula among the parents and offspring were also found.     

A field study of the ecology and behavior of the black-mantle tamarin (Saguinus nigricollis)

The author made an ecological study of the black-mantle tamarin (Saguinus nigricollis) in the primary forest in the basin of the River Caquetá in the upper Amazon in Colombia for 88 days during a study period from August 1975 to February 1976. The tamarin group repeats three activity patterns — feeding, resting, and moving — regularly in a day. In their feeding activity, the tamarins preferred to eat small insect and resin. They showed a special liking for large grasshoppers, 6–8 cm long, and spent much of the day to capture them. Moving in search of the grasshoppers, which are hard to capture in the forest, is closely related to the tamarin group's daily nomadism. From this evidence it can be concluded that the behavior which forms the basis of the tamarins' daily activity is the hunting of grasshoppers. In the transition time from the feeding activity, principally the hunting of grasshoppers, to the resting activity, a fruit eating behavior was always observed. At this time the tamarins ate well-ripened sweet fruit intensively for a short time. This behavior is thought to have the effect, in one respect, of easing strained relations arising among group members during the grasshopper hunting activity. It was also observed that mother tamarins shared their hard-to-capture grasshoppers with their offspring although the latter had already become independent of their mothers. In general, the tamarins lived in a small and compact group consisting of an adult male, an adult female, and their offspring. Some of these small groups had amicable interrelationships and often moved together, whereas other groups kept aloof from each other. These facts indicate that, besides the groups as the social units, large-groups comprising some of these unit groups moving together, exist in the social structure of the tamarins, and form the upper structure of the social unit. See the note added to the end of this article.     

The skin of primates. XXXIX. The skin of the white-browed capuchin (Cebus albifrons)

The skin of the white-browed capuchin (Cebus albifrons), although basically similar to that of the squirrel monkey (Saimiri sciureus), contains several outstanding peculiarities: (1) both the epidermis and dermis of the general body surface are devoid of melanotic melanocytes; (2) the skin of the prehensile tail has no modified, glabrous friction surface; (3) the prehensile surface of the tail has no specialized nerve end-organs; (4) cholinesterase-positive, papillary nerve end-organs rest beneath the epidermal ridges of volar skin; and (5) both the clear cells and dark cells of the eccrine glands contain glycogen but neither shows phosphorylase activity.     

The skin of primates. XXXVII. The skin of the pig-tail macaque (Macaca nemestrina)

The skin of the pig-tail macaque is basically similar to that of the rhesus monkey and the stump-tail macaque. The epidermis is thin and contains occasional basal melanocytes. The dermis, rich in elastic fibers, is practically free of pigment-containing cells. The upper dermis is highly vascular in the perianal region and sex skin. Cholinesterase-reactive nerve endings are plentiful beneath the friction surfaces of the pes and manus, mucous membranes, and junction of the hairy gluteus and glabrous ischial callosity. Hederiform-like endings are present in the eyelid, pinna, and frontal scalp. Apocrine and eccrine sweat glands occur throughout the hairy skin in a 2–3: 1 ratio. Both types are invested by nerves reactive for acetyl- and butyrylcholinesterase.     

The skin of primates. XXX. The skin of the woolly monkey. (Lagothrix lagotricha)

The anatomical and histochemical features of the skin of the woolly monkey are intermediate between those of the Cercopithecoidea and the Pithecoidea. The animal has a prehensile tail, the glabrous, friction surface of which is similar to that of the fingers. The epidermis is heavily pigmented. The dermal vascularization is relatively well-developed and similar to that of the skin of the Cercopithecoidea. Hair follicles grow in groups of 4 to 15, as in the skin of the Pithecoidea. In the hairy skin, eccrine sweat glands occur only in the tail and genitalia. The woolly monkey, like the green monkey, possesses only acetylcholinesterase-containing nerve fibers around its eccrine sweat glands.     

The skin of primates. 28. The stump-tail macaque (Macaca speciosa)

Though having some similarities to that of the rhesus monkey, the skin of the stump-tail macaque has several unique features. The epidermis has a sparse population of active melanocytes, and there is practically no pigmentation in the dermis. The dermis is rich in elastic fibers, the function of which seems to be to anchor the hair follicles and the arrectores pilorum muscles, and the superficial blood vessels. Large numbers of eccrine and apocrine sweat glands in the forehead and scalp are reminiscent of the axillary organ in the Hominioidea. The very large sebaceous glands on the face and bald forehead and scalp resemble those of man. The forehead and anterior portion of the scalp are bald in the adult but not in juvenile animals. In spite of an apparently rich pelage, these animals seem to show a trend toward nakedness.     

The skin of primates. XLIII. Further observations on the Philippine tarsier (Tarsius syrichta)

Underneath the volar friction surfaces is a highly developed, anastomosing system of alkaline phosphatase-reactive capillaries; numerous cholinesterase-positive hederiform nerve end-organs are present in the scalp, forehead, lower abdomen, back, and perianal region; sinus hair follicles occur on the flexor surface of the antebrachium; and a dense field of gigantic sebaceous and admixed apocrine glands constitutes the epigastric gland.     

The skin of primates. XLIV. Numerical taxonomy of primate skin

Data on 84 characteristics of the skin of 36 species of primates were extracted from a series of articles describing the histological and histochemical properties of the skin of primates. The data were subjected to a cluster analysis. The results were in reasonably good agreement with orthodox primate taxonomies although some exceptions were apparent. The species clustered into four main groups approximately comparable to Prosimii, Cercopithecoidea, Ceboidea, and Hominoidea. The internal arrangements of the Prosimii, Cercopithecoidea, and Hominoidea are commensurate with standard taxonomic practice. Within the Ceboidea, however, the Atelinae and Alouattinae tend to group with the Hominoidea, Aotus and Saimiri show variable placements, and Callimico groups with the Callithricidae.     

The skin of primates. XL. The skin of the cottontop pinché Saguinus (=Oedipomidas) oedipus

The skin of Saguinus (= Oedipomidas) oedipus Linnaeus, is basically similar to that of the red-mantled tamarin, Saguinus (= Tamarinus) fuscicollis Spix; it has several peculiarities: (1) a circumscribed tuft of vibrissae on the ulnar aspect of the wrist; (2) an accumulation of apocrine glands over the sternum; and (3) an extensive posterior abdominal field of gigantic sebaceous glands admixed with large apocrine glands, better developed in the female. The epidermis, dermis, hair follicles, sebaceous ducts, and apocrine excretory ducts are all heavily pigmented. Hairs are arranged in linear perfect sets; the epithelial sac of quiescent follicles is devoid of glycogen and phosphorylase. Eccrine sweat glands are restricted to the volar friction surfaces and contain no glycogen. Only the coiled excretory ducts of the eccrine glands contain phosphorylase. All cutaneous nerve fibers are more reactive for acetylthan butyrylcholinesterase.     

Locomotor behavior and feeding ecology of the panamanian tamarin (Saguinus oedipus geoffroyi,callitrichidae, primates)

The Callitrichidae are a family of New World primates that exhibit a complex of behavioral and morphological characters reputedly similar to those of tree squirrels of the genus Sciurus.In particular, the locomotor behavior of tamarins and marmosets has been described as “squirrel-like. ” In this paper I describe a field investigation of the locomotor behavior and ecology of the Panamanian tamarin (Saguinus oedipus geoffroyi)and the redtailed squirrel (Sciurus granatensis).From January through August 1978, a total of 1200 hr was spent observing freeranging populations of tamarins and tree squirrels in an area of secondary forest on the Pacific Coast of Panama. Observations were made using an instantaneous time sampling technique. Individual activity records were collected on focal animals and recorded at 2.5-min intervals throughout the day. The following information was collected: (a) nature and structure of the substrate exploited, (b) activities on these supports and/or types of resources procured, and (c) body posture involved in the use of these supports. Data presented indicate major differences in substrate preference and positional behavior in tamarins and tree squirrels. Unlike squirrels, tamarins avoid vertical and sharply inclined supports during travel. Movements through the canopy is accomplished by a series of long leaps which begin and end on thin terminal supports. However, the Panamanian tamarin spent numerous hours clinging to large vertical trunks while feeding on plant exudate. Gums comprise 23.O% of the noninsect portion of the tamarin diet. The relationships between small body size, claw-like nails, substrate preference, and positional behavior are discussed. Claw-like nails enable this primate to exploit a food resource that would otherwise be inaccessible. The interrelationship between environment, behaviour, and morphology provides a frameworks from which to understand callitrichid adaptations. These adaptations are not convergent with those of the sciurid rodents. An earlier draft of this paper was presented at the 48th Annual Meeting of the American Association of Physical Anthropologists, San Francisco, April 1979.     

Adrenal myelolipoma in the cottontop tamarin (Saguinus o. oedipus)

Two cases of myelolipoma in the cottontop tamarin (Saguinus o. oedipus) were found unequivocally within the adrenal gland, supporting an earlier suggestion that the adrenal gland was the possible origin of a juxtarenal myelolipoma in the same species. In the present study a 30-mm-diameter myelolipoma was present in the adrenal gland in case 1, whereas in case 2 the myelolipoma was only detected on histological examination. In case 1, changes in the adrenal gland were considered to be of minor clinical significance, whereas in case 2 the myelolipoma was an incidental finding.     

Rearing of conventional and gnotobiotic nonhuman primates (Pan troglodytes, Papio cynocephalus, Saguinus nigricollis).

Rearing techniques for conventional and gnotobiotic nonhuman primates are described. Up to four months of age there was no significant difference in weight gain between conventionally and gnotobiotically reared chimpanzees or baboons. After four months, gnotobiotic chimpanzees exceeded their conventional counterparts in weight gain, whereas conventional baboons showed higher weight gain than gnotobiotic baboons. Gnotobiotic chimpanzees and baboons had significantly lower absolute numbers of neutrophils than their conventional counterparts, but the absolute numbers of lymphocytes were not different. The gnotobiotic rearing of marmosets is also reported.