Reproductive performance of three species of Callitrichidae

The reproductive performance of three species of Callitrichidae housed under identical conditions, including relatively spacious caging and visual screening, was compared. The three species were Callithrix jacchus, Saguinus fuscicollis, and Saguinus oedipus. Callithrix jacchus was the most reliable breeder, with the lowest percentage of stillborn and the highest post-weaning survival. While the reproductive performance of S oedipus was better than that generally reported for other colonies, the reproductive performance of the Saguinus species was still poorer than that of C jacchus. The two Saguinus species did not differ significantly in either percentage of stillborn or post-weaning survival. None of the species showed infertility due to lactation, but the mean inter-birth interval was significantly longer for S oedipus than for either C jacchus or S fuscicollis.     

Species differences in response to conspecific intruders inCallithrix jacchus andSaguinus oedipus

In this study, the first performed on two species of callitrichid primates under identical conditions, the responses elicited in newly mated individuals by conspecific intruders were compared in four pairs of Callithrix jacchusand four pairs of Saguinus oedipus.Intruders were systematically varied in terms of sex and the social context in which they were met. Clear sexual dimorphism was observed in the behavior of Saguinus oedipus,but the behavior of males and females was less dimorphic in Callithrix jacchus.Males and females of both species showed an increase in agonistic and display behavior in the presence of same-sex intruders, but the mode of behavior varied both with sex and species. Social facilitation, as indicated by increased frequencies of agonistic and display responses in the presence of a mate, was observed only in males of both species. Neither C. jacchusnor S. oedipusdisplayed clear evidence of a monogamous mating system like that of Callicebusor of a polygynous mating system like that of Saimiri.Observed differences in the responses to conspecifics between these two species in the laboratory may be explained by facultative differences in mating systems resulting from differences in ranging and foraging behavior under freeranging conditions.     

Patterns of positional behavior in mixed-species troops of Callimico goeldii, Saguinus labiatus, and Saguinus fuscicollis in northwestern Brazil

We present the results of a 4-month field investigation of positional behavior, vertical ranging, and species differences in limb proportions and body mass in a mixed-species troop of Saguinus fuscicollis, Saguinus labiatus, and Callimico goeldii in northwestern Brazil. Despite certain similarities in overall positional repertoire, patterns of positional behavior varied significantly between species. Travel in Callimico occurred principally in the lowest levels of the canopy, and was characterized by an exaggerated form of hindlimb-dominated bounding (bounding-hop), and leaping to and from vertical trunks (55.1% of leaps). In contrast, saddle-back tamarins traveled in the lower and middle levels of the canopy, and engaged in a range of leaping behaviors, including stationary leaps (37.3%), acrobatic leaps (31.3%), and trunk-to-trunk leaps (20%). Red-bellied tamarins exploited the highest levels of the arboreal canopy. Travel in this species was dominated by quadrupedal bounding and acrobatic leaps (67% of leaps) that began and ended on thin, flexible supports. Species differences in positional behavior correlated with species differences in limb proportions and locomotor anatomy, and provide a framework for understanding niche partitioning in mixed-species troops of Saguinus and Callimico.     

Chromosome banding patterns and nucleolar organizing regions in three species of Callithricidae (Saguinus oedipus, Saguinus fuscicollis, and Callithrix jacchus).

Chromosome complements of three species of Callithricidae, Saguinus oedipus, Saguinus fuscicollis and Callithrix jacchus, were analyzed by various banding techniques. Morphometric data are presented. A diploid chromosome number of 2n = 46 is reconfirmed for all three species. Several interesting interspecies chromosomal variations were demonstrated by G- and C-band patterns. Active nucleolar organizing regions (NORs) were revealed by the Ag-AS silver histochemical stain.     

Genetic variations in albumin and transferrin as species markers in plasma of Callithricidae

Albumin (Alb) and transferrin (Tf) polymorphism in plasma of Callithricidae was investigated by means of starch gel electrophoresis. In 52 blood samples of three species (Saguinus mystax, S. oedipus and S. labiatus), four Alb phenotypes (Alb 1, Alb 2, Alb 3 and Alb 2-3) and two Tf phenotypes (Tf 1 and Tf 2) were observed. No Alb variant was found in S. oedipus and S. mystax.     

A comparative study of positional behavior in three species of tamarin monkeys

Tamarins of the genusSaguinus are small-bodied New World monkeys that exhibit clawlike or modified nails. Patterns of positional behavior and habitat utilization are presented for three species,Saguinus fuscicollis, S. geoffroy, andS. mystax. These data were collected on free-ranging tamarin populations in Panama and Peru. Despite considerable differences in body weight, all three species exhibited very similar patterns of positional behavior, with quadrupedal bounding and running accounting for 43 – 52% of travel time. Leaping was the second most common locomotor activity and accounted for 31 – 41% of travel. Although each species leaped principally on small supports in the perimeter of the tree crown, approximately 20% of all leaps inS. fuscicollis involved moderate to large sized vertical trunks located in the undercanopy. Leaping between trunks was rare in the two larger tamarin species. Measurements taken on live wild-trapped adults reveal that compared toSaguinus geoffroyi andS. mystax, S. fuscicollis is characterized by a long legspan and an especially long armspan. It is proposed that inS. fuscicollis, elongated forelimbs play an important role in maneuvering and rotating the body during the in-air phase of trunk-to-trunk leaping, and increase the breaking distance needed to decelerate the body upon impact. Additional relationships between body size, substrate preference, and positional behavior in callitrichines are discussed.     

Relationship between social interactions and sexual maturation in female Saguinus oedipus oedipus

4 female Saguinus oedipus oedipus were paired with strange, unrelated males while 5 remained in their natal family groups. A comparison of the frequency of selected social interactions involving these females when sexually immature versus mature was made. The frequency of sexual and affiliative interactions in male-female pairs was basically unchanged by the female's maturation. Mother-daughter interactions were also not changed in a consistent fashion by the daughters' maturation. Females with strange, unrelated males, either alone or as part of their natal group, displayed increases in marking behavior in association with sexual maturation.     

Arboreal locomotion in small new-world monkeys

The postural and locomotor activity and its relation to substrates was observed in 3 Saguinus oedipus, and 3 Saimiri sciureus for comparison, during a period of 10 h for each individual. The animals moved freely in cages of 3.40 m x 3.40 m x 2.40 m (height) on rather diverse substrates. Observations were made according to the focal-animal-method, with combined instantaneous and continuous sampling. They were protocoled in schematic form and video-recorded. In addition, 3 further Saguinus oedipus were subjected to an X-ray cinematographic study on a modified treadmill to unveil metric parameters of the locomotor pattern preferred on slender and compliant ("arboreal") substrates, the walk. Independent from the substrates, the postures of the two species differed in details, as do the preferred substrates. Horizontal, comfortable substrates are favored most. Walking ranked top in frequency, followed by jumping and galloping (in a strict sense). All other locomotor modes described for primates played a minor role or lacked entirely, like the trot. Average distance of leaps was only 0.60 m, landings were mainly on the same level as take-offs. In Saguinus, the movements of both limbs, including the shoulder blade, followed the pattern common to small mammals in general: At the end of the stance phase, humerus and tibia are nearly parallel to the substrate, while just before touchdown ulna and femur are in this position. The walk in both species was surprisingly fast (1 m/s), reaching the speed of much larger cursorial animals, like humans.     

Isolation of a cytomegalovirus from salivary glands of white-lipped marmosets (Saguinus fuscicollis).

Minced salivary glands from seven white-lipped marmosets (Saguinus fuscicollis and Saguinus nigricollis) and one cotton-topped marmoset (Saguinus oedipus) were cocultivated with marmoset cell cultures. A viral agent, designated SSG, was isolated from two Saguinus fuscicollis. Slowly progressing foci of rounded, vacuolated, refractile cells were first observed at 40-43 days incubation. Electron microscopy revealed intranuclear herpesvirus nucleocapsids and intracytoplasmic and extracellular enveloped particles. Infected cells stained with hematoxylin and eosin contained eosinophilic intranuclear and cytoplasmic inclusion bodies. SSG could be passaged in cell cultures only using viable whole cells; infectious cell-free virus was not detected in either culture supernatants or cell lysates. SSG replicated in marmoset fibroblastic but not in marmoset epithelioid or human fibroblastic cell cultures. Plasma antibodies to SSG were detected by indirect immunofluorescence assays in 16 of 56 (28.6%) adult wild-caught marmosets but were absent in 40 colony-born, hand-reared marmosets. Antigenic cross-reactivity of SSG with a rhesus monkey (Macaca mulatta) cytomegalovirus (bidirectional) and with a human cytomegalovirus (unidirectional) was also demonstrated by indirect immunofluorescence assays. SSG was identified as a herpesvirus by morphology and was classified as a cytomegalovirus by its site of isolation, biologic properties in vitro, and antigenic characteristics.     

Adrenal gland tumours in two cotton-top tamarins (Saguinus oedipus oedipus)

Two adrenal gland tumours in captive born cotton-top tamarins (Saguinus oedipus oedipus) are described. One was a pheochromocytoma in a 14-year-old male, the other one a cortical adenoma in a 7.5-year-old female. Both were associated with morphological signs of myocardial damage and circulatory problems. The findings are discussed and compared to adrenal gland tumours in man.     

Field Techniques for Monitoring Cotton-Top Tamarins (Saguinus oedipus oedipus) in Colombia

We present reliable field techniques for capturing, anesthetizing, and Iidentifying individual cotton-top tamarins (Saguinus oedipus oedipus). A new technique is presented for radio-tracking small bodied primates. A backpack-style harness was designed to carry a transmitter. This system appears effective in minimizing potential injury and does not appear to interfere with the normal behavior of the animal. © 1993 Wiley-Liss, Inc.     

Congenital anomalies in two neonatal tamarins (Saguinus oedipus and Saguinus fuscicollis)

Congenital anomalies were seen at necropsy of two neonatal tamarins. The defects included achondroplastic-like dwarfism, polydactyly and syndactyly in a Saguinus oedipus, and scoliosis and uterus didelphys in a S. fuscicollis. Both infants were the offspring of incestuous matings between twin siblings.     

The Effect of the Captive Environment on Activity of Captive Cotton-Top Tamarins (Saguinus oedipus)

This study examined captive cotton-top tamarin (Saguinus oedipus) behavior across 3 different exhibits: (a) a rainforest (30.5 m in diameter), where tamarins free-ranged with other species; (b) a caged outdoor exhibit (5 m in diameter); and (c) a caged enclosure, with access indoors (6 × 9m) and outdoors (2.5 × 2.5 m). The study observed tamarins using focal animal scan sampling in 10 min blocks. Scoring was on the percentage of intervals in which they engaged in 12 behaviors. The findings show significant differences in activity, inactivity, and visibility across exhibits and have important implications for reintroduction efforts.     

The effect of the captive environment on activity of captive cotton-top tamarins (Saguinus oedipus)

This study examined captive cotton-top tamarin (Saguinus oedipus) behavior across 3 different exhibits: (a) a rainforest (30.5 m in diameter), where tamarins free-ranged with other species; (b) a caged outdoor exhibit (5 m in diameter); and (c) a caged enclosure, with access indoors (6 × 9m) and outdoors (2.5 × 2.5 m). The study observed tamarins using focal animal scan sampling in 10 min blocks. Scoring was on the percentage of intervals in which they engaged in 12 behaviors. The findings show significant differences in activity, inactivity, and visibility across exhibits and have important implications for reintroduction efforts.     

Hand specialization, sympatry, and mixed-species associations in callitrichines

Hand morphology in callitrichines (i.e., tamarins, marmosets, and Goeldi's monkey) is correlated with positional and foraging behaviors. This study examines hand shape in callitrichines using an allometric approach. It addresses a series of questions relating hand anatomy, insect foraging behavior, and resource partitioning in callitrichines. The main questions are: 1. Do the hands of Leontopithecus differ in shape from all other callitrichine taxa allowing it to perform highly manipulative prey foraging behaviors? 2. Are the hands of Saguinus fuscicollis adapted to manipulative foraging, and are they functionally similar to Leontopithecus' hands? 3. Is hand morphology in S. fuscicollis more similar to the hand morphology of sympatric tamarin species with whom it does not form mixed species troops (S. nigricollis and S. tripartitus) than to those sympatric tamarin species with whom it does form mixed troops (S. mystax, S. labiatus, and S. imperator)? Measurements of hand length (HL), width (HW), and thickness (HT) were taken from 1350 museum specimens of callitrichines (Callithrix, Cebuella, Leontopithecus, Saguinus, and Callimico), squirrel monkeys (Saimiri), and owl monkeys (Aotus). The analysis indicates that hand shape covaries with foraging strategy. Specifically, the hands of Leontopithecus are adapted for manipulative foraging and are relatively longer and more slender than the hands of other callitrichines. A similar pattern is observed in the hands of S. fuscicollis, S. tripartitus and S. nigricollis. These latter species, however, differ significantly in shape from all other tamarin species. Large differences in hand morphology are observed among tamarin species that form mixed-species troops. These anatomical differences may permit resource partitioning and coexistence among these closely related taxa. Hand shape, expressed as log HLGM (logged hand length divided by the geometric mean of all measurements), is a good predictor of manipulative and non-manipulative prey foraging techniques employed by callitrichines.     

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.     

The involucrin genes of the white-fronted capuchin and cottontop tamarin: the platyrrhine middle region.

In all anthropoid species, the coding region of the involucrin gene contains a segment of short tandem repeats that were added sequentially, beginning in a common anthropoid ancestor. The involucrin coding region of each of two platyrrhine species, the white-fronted capuchin (Cebus albifrons) and the cottontop tamarin (Saguinus oedipus), has now been cloned and sequenced. These genes share with the genes of the catarrhines the repeats added in the common anthropoid lineage (the early region). After their divergence, the platyrrhines, like the catarrhines, continued to add repeats vectorially 5' of the early region, to form a middle region. The mechanism that was established in the common anthropoid lineage for the addition of repeats at a definite site in the coding region was transmitted to both platyrrhines and catarrhines, enabling each to generate its middle region independently. The process of vectorial repeat addition continued in two platyrrhine sublineages after their divergence from each other.     

Pregnancy weight gain: marmoset and tamarin dads show it too

Paternal behaviour is critical for the survival of offspring in many monogamous species. Common marmoset (Callithrix jacchus) and cotton-top tamarin (Saguinus oedipus) fathers spend as much or more time caring for infants than mothers. Expectant males of both species showed significant increases in weight across the pregnancy whereas control males did not (five consecutive months for marmoset males and six months for cotton-top tamarin males). Expectant fathers might be preparing for the energetic cost of fatherhood by gaining weight during their mate's pregnancy.     

Sexual dimorphism in responses to unfamiliar intruders in the tamarin, Saguinus oedipus

Aspects of social structure in group-living species can be inferred by observing the responses of individuals to unfamiliar animals. This study examined the responses of mated pairs of cotton-top tamarins (Saguinus oedipus oedipus) to presentation of either unfamiliar conspecifics or members of a related tamarin species, the saddle-back tamarin (Saguinus fuscicollis fuscicollis). Male and female responses to intruders differed: resident males threatened, displayed piloerection, approached, and attacked intruders, especially males, while resident females showed increases in suprapubic scentmarking in the presence of intruders. Both males and females discriminated between the species of intruders, exhibiting more threats, scent-marking, piloerection, and approaches in the presence of conspecific intruders. There are pronounced sex differences in the signals and behaviour patterns that are elicited in an aggressive or territorial encounter with unfamiliar conspecifics in this monogamous primate.     

The units of perception in the antiphonal calling behavior of cotton-top tamarins (Saguinus oedipus): playback experiments with long calls

We investigated how the acoustic structure of the cotton-top tamarin monkey's (Saguinus oedipus) combination long call relates to the antiphonal calling behavior of conspecifics. Combination long calls can function as contact calls and are produced by socially isolated individuals. Often conspecifics respond to these calls with their own long calls. Structurally, these calls are always composed of one or more 'chirps' followed by two or more 'whistles'. We compared the antiphonal calling responses to playbacks of complete, naturally produced long calls versus single whistles or single chirps. Subjects responded significantly more to whole calls than to either syllable-type alone. Thus, our data suggest that, in terms of the antiphonal calling behavior of socially isolated conspecifics, the whole long call is the unit of perception.