The karyotype of Galago alleni Waterhouse 1837 (2N=40), compared with that of Galago senegalensis Geoffroy 1796 (2N=38) (primates,prosimii, Galagidae)

In a broader project on the cytogenetics of the Galagidae the chromosomal complement of a female Galago alleni was studied. The karyotype, consisting of 40 chromosomes, is described and compared with the karyotype found in three individuals of Galago senegalensis with 38 chromosomes.This study was supported by Grant No. 82-34 of the Netherlands Organization for the Advancement of Pure Research (Z.W.O.).     

Acacia gum and its use by bushbabies,Galago senegalensis (Primates: Lorisidae)

Lesser bushbabies (Galago senegalensis moholi)were studied by radiotracking over a 2-year period (August 1975 to August 1977)at a thornveld study site in the Northern Transvaal, South Africa. It was confirmed that the diet consisted exclusively of plant exudates (gums) and arthropods;available fruits were never eaten. The gums were taken from the trunks and branches of Acaciatrees, particularly from Acacia karroo(the major source), from A. tortilis,and to a small extent from A. nilotica.Chemical analysis shows that gums consist predominantly of carbohydrates and water, with small quantities of fiber, protein, and minerals (notably calcium, magnesium, and potassium). Thus, the gums probably present first and foremost a source of carbohydrate in the diet of the lesser bushbaby, though it seems likely that special mechanisms must exist for digestion of the polymerized pentose and hexose sugars. The calcium content of the gums (approx. 1% by weight) is probably significant in offsetting the low calcium content of the arthropod prey, and their high calcium:phosphorus ratio may well counterbalance the low calcium:phosphorus ratio of the arthropods. The gums are apparently produced largely in response to insect activity. Larvae of beetles (families Cerambycidae,Buprestidae, and Elateridae) and of moths (family Coccidae) bore channels beneath the tree surface, and gum is liberated through apertures made during invasion of the host Acacia.Fly larvae (family Odiniidae) may also develop in the gumfilled cavities. Gum exuding onto the surface is collected by the bushbabies on regular nightly visits, and firm evidence was obtained, in the form of characteristic marks on trap baseboards and certain gum sites, that the toothscraper in the lower jaw is used to scoop away gum from tree surfaces. Foraging for, and feeding upon, gum increased during the winter months, which may be particularly harsh in certain years. In the especially cold winter covered by the study, insect availability was minimal and the lesser bushbabies fed mainly on gum, with some of them reducing their total activity period during the night. Gums are available throughout the year and detailed records indicated no clearcut seasonal pattern of gum production. They are therefore an important yearround food resource for the lesser bushbabies. Feeding on gums has been reported for a wide range of primate species in recent years (especially for various species of the families Cheirogaleidae, Lorisidae, and Callitrichidae), and these plant exudates must now be regarded as an important dietary category within the order Primates.     

Ultrasonographic aspects of the Leontopithecus gestation (Lesson, 1840—Callitrichidae,Primates)

Background

There is a concern about conservation of endangered species today. Among this species, the Leontopithecus (Lesson, 1840) is outstanding. Its population has been whirling reduced. So far the reproductive physiology of Leontopithecus has few studies, it is fundamental requisite to preserve this species. Obstetric sonography has become an essential method in reproductive management of primates.

Method

This method is very helpful to detect early pregnancy and evaluate some deficiency of fetal growth. In this study, 14 pregnancies were monitored using real‐time abdominal sonography. During each evaluation, the number of fetus was recorded, gestational sac and heart beats were observed, and biparietal diameter was measured.

Results

The results showed that abdominal sonography is a reliable method for observation of gross morphological changes during pre‐natal development and to estimate gestational age. No statistically differences were observed between twins and singletons. This study is the first investigation of pre‐natal growth in Leontopithecus.     

Field and laboratory studies of social organization in Bushbabies (Galago senegalensis)

During the course of a one year field study of the Lesser Bushbaby (Galago senegalensis moholi), using a technique of direct observation with red light, it was discovered that family groups which slept together during the daytime split up at night, with each member spending most of the time alone. During the night individuals would come into contact with one another or with members of adjacent groups and the resulting social behaviour varied considerably. An interpretation has been made of more than 120 interactions observed in the field based on the behaviour of bushbabies introduced to one another under controlled semi-natural conditions.     

Male Territoriality in the Bumblebee Wolf,Philanthus bicinctus (Mickel) (Hymenoptera,Sphecidae): Observations on the Behaviour of Individual ♂♂

Observations were made on the behaviour of male Philanthus bicinctus (Mickel) which defend territories around the nesting burrows of ♀♀. ♂♂ were individually identified with small number tags and focal-animal samples were taken of the behaviour of these ♂♂. Intense interactions were observed between territorial ♂♂ and 1) conspecifics and 2) intruding insects which resembled conspecifics. Evidence is presented which suggests that ♂♂ scent mark their territories.     

Standardized karyotypes for the greater Galagos,Galago crassicaudatus E. Geoffroy, 1812 and G. garnettii (Ogilby, 1838) (Primates: Prosimii)

Karyotypes were analyzed of 21 greater galagos, usign classical, G-banding, C-banding and silver nitrate staining techniques. A composite G-banded karyotype and high resolution idiogram are presented for each species. Areas of possible rearrangement are identified. The results support the interpretations derived from earlier, unbanded studies, rather than a more recent proposal from G-banded data. Failure of repeated attempts to obtain C-bands, despite success in human controls, indicates that the heterochromatic bands generally revealed by these staining methods are either absent or extremely small in greater galagos. Silver staining revealed a single pair of NOR-bearing autosomes in both species, as shown by previous authors.     

The Equivocal Relationship Between Territoriality and Scent Marking in Wild Saddleback Tamarins (<Emphasis Type="Italic">Saguinus fuscicollis</Emphasis>)

Researchers have often assumed that scent marking serves a territorial function in callitrichines, although some controversy exists. To fulfill such a function, scent marks should 1) prevent intrusions, 2) ensure access to feeding resources, 3) enable avoidance of intergroup encounters, or 4) play an important role in the aggressive encounters between groups. We studied 13 saddleback tamarins (Saguinus fuscicollis) belonging to 3 free-ranging groups, which formed mixed-species troops with moustached tamarins (S. mystax) in the Amazonian rain forest of Peru. None of the predictions were confirmed. The tamarins used a border-marking strategy, marking more on the periphery of their territory. However, feeding trees in overlap and encounter areas received more scent marking but were still visited by neighboring groups. Intergroup encounters occurred more often than expected, and scent-marking frequency was not higher during them than when no other group was present. It appears that instead of defending a territory in the classic sense, the tamarins are optimizing signal transmission by depositing their scents where the probability of detection by neighbors is higher. Saddleback tamarins may use shared areas of their home ranges to exchange information with neighboring groups, perhaps regarding reproductive opportunities.     

Functional morphology of the feeding system in the ruff — Gymnocephalus cernua (L. 1758) — (Teleostei,Percidae)

The ruff, Gymnocephalus cernua, is a European freshwater fish that feeds by sucking up small invertebrates from the bottom of ponds and slow flowing rivers. The feeding movements have been studied by simultaneous electromyography of seventeen muscles of the head and cinematographic techniques. A theoretical model of movements imposes the functional demands of suction upon an abstraction of the form of a teleost head. Three phases in the feeding act, a preparatory phase, a suction phase and a transport phase, could be correlated with the observed movements and EMGs. Differences between the predicted and the actual movement are discussed. Two different types of feeding occur. The direction, magnitude and duration of the suction forces during feeding are modified, according to the position of the prey. A mechanism preventing early mandibular depression allows sudden and strong suction. Retardation of the suspensorial abduction during the overall expansion of the buccal cavity is ascribed to kinetic interrelations with the hyoid arch. Protrusion of the upper jaws also permits an earlier closure of the mouth and directs the food-containing waterflow posteriorly. When the fish is feeding on sinking prey, protrusion occurs later in the sequence of movements than when it is feeding from the bottom. As the protruded jaws produce a downwardly pointed mouth this retardation aims the suction force.     

Field observations on scent-marking behaviour in saddle-back tamarins, Saguinus fuscicollis (Callitrichidae, Primates)

The scent-marking behaviour of a group of six saddle-back tamarins, Saguinus fuscicollis nigrifrons , was studied in the Amazon rain forest of north-eastern Peru. Three types of scent marking were recognized: anogenital marking, suprapubic marking and sternal marking. Anogenital marking was the most frequent type. Two or more scent-marking acts of the same or different type were generally combined into sequences. Most scent-marking was performed on branches and lianas; trunks were infrequently used. The tamarins mainly marked on horizontal or inclined substrata with diameters between 3 and 10 cm and a height between I and 10 m. The temporal distribution of scent-marking exhibited a maximum in the early morning between 06:00 and 07:00h and a minimum between 16:00 and 17:00h. The majority of scent-marking occurred in the peripheral areas of the home-range. The spatial distribution of scent-marking was correlated with the intensity of home-range use. No elevated frequencies of scent-marking were observed during intergroup encounters. The results of this field study are compared with findings from laboratory studies, and hypotheses concerning the function of scent-marking are discussed.     

A new karyotype in Callicebus torquatus (Cebidae, Primates)

We describe a new karyotype of Callicebus torquatus using conventional staining, G-banding with Wright Stain, CBG, Ag-NOR staining and fluorescence in situ hybridization (FISH) with human telomere probes and comparative analysis with the previously reported karyotype of C. torquatus torquatus (2n = 20). We studied a female specimen maintained in captivity at the Centro Nacional de Primatas (Para, Brazil). This titi monkey presented 2n = 22, with four large biarmed and six acrocentric autosome pairs; the X chromosome is a medium submetacentric. C-bands were revealed at the centromeric region of all acrocentrics and X chromosome; punctual C-bands also are visualized at the centromeric region in the large biarmed pairs. The NOR site was located at the long arm of pair 4, at the position of a conspicuous secondary constriction. Hybridization signals were detected exclusively at the terminal region of all chromosomes. The karyotype described here has one acrocentric pair more than that found in the literature and also differs by amount and distribution of constitutive heterochromatin. Our data support the notion that the torquatus group may be composed of distinct species, each with its own karyotype.     

Primates and Plesiadapiformes from Cos (Eocene; Quercy,France)

A new fauna has been collected from a fissure filling named Cos in the Quercy region, southwestern France. It includes four primate species and a plesiadapiform. The cercamoniine adapiform Protoadapis andrei Godinot and Vidalenc, nov. sp., is represented by material that adds to our knowledge of the genus Protoadapis for the upper canine, upper molars and other morphological details. It appears more primitive than P. brachyrhynchus from the Old Quercy Collections. The other cercamoniine Pronycticebus cosensis Godinot and Vidalenc, nov. sp., offers insight on intraspecific variations and other details of the genus. Both species suggest a bushy evolution within these genera. Two teeth document the presence of a third cercamoniine, Anchomomys sp. indet. The new microchoerid Quercyloris eloisae Godinot and Vidalenc, nov. gen., nov. sp., has very primitive characters and seems to document a primitive member of the Pseudoloris clade. A poorly documented paromomyid plesiadapiform is distinct enough to be named Arcius moniquae Godinot and Vidalenc, nov. sp. It represents the first discovery of a plesiadapiform in the Quercy fossil record and makes a link with paromomyids surviving until the late Lutetian European Mammal Paleogene MP 13 reference level. The primates indicate a broad age interval between MP 10 (late Ypresian) and MP 12 (mid-Lutetian). The identification of the same species of Pronycticebus and of the new genus in the Vielase fauna suggests more precisely the MP 10–MP 11 (late Ypresian–early Lutetian) time interval.     

Agonistic Behaviour and Development of Territoriality During Ontogeny of the Sea Anemone Dwelling Crab Allopetrolisthes Spinifrons (H. Milne Edwards, 1837) (Decapoda: Anomura: Porcellanidae)

Allopetrolisthes spinifrons is an ectosymbiotic crab of the sea anemone Phymactis clematis . As a consequence of low host abundance, these represent a scarce and limited resource for the crab. Additionally, the relatively small size of the sea anemone host suggests that few symbiotic crabs can cohabit on one host individual, forcing crabs to adopt a territorial behaviour. In order to examine the potential presence and ontogenetic development of territoriality, the agonistic behaviour between crabs of various ontogenetic stages (adults, juveniles, and recruits) was studied in the laboratory. Laboratory experiments demonstrated that adult or juvenile crabs aggressively defended their sea anemone hosts against adult or juvenile intruders, respectively, but both adult and juvenile crabs tolerated recruits. Adult crabs behaved indifferently towards juvenile crabs, sometimes tolerating them, sometimes expelling them. Recruits never showed agonistic behaviour among themselves. The agonistic interactions observed in the laboratory and the uniform population distribution pattern on sea anemones recently described for A . spinifrons indicate that this species exhibits territorial behaviour, which develops during ontogeny. Territoriality in this species and other symbiotic decapods may function as a density-dependent mechanism of population regulation, being mediated by the availability of hosts. Resource monopolisation behaviours may be common among other symbiotic and free-living marine invertebrates inhabiting discrete habitats that represent a limiting resource.     

Agonistic Behaviour and Development of Territoriality During Ontogeny of the Sea Anemone Dwelling Crab Allopetrolisthes Spinifrons (H. Milne Edwards, 1837) (Decapoda: Anomura: Porcellanidae)

Allopetrolisthes spinifrons is an ectosymbiotic crab of the sea anemone Phymactis clematis. As a consequence of low host abundance, these represent a scarce and limited resource for the crab. Additionally, the relatively small size of the sea anemone host suggests that few symbiotic crabs can cohabit on one host individual, forcing crabs to adopt a territorial behaviour. In order to examine the potential presence and ontogenetic development of territoriality, the agonistic behaviour between crabs of various ontogenetic stages (adults, juveniles, and recruits) was studied in the laboratory. Laboratory experiments demonstrated that adult or juvenile crabs aggressively defended their sea anemone hosts against adult or juvenile intruders, respectively, but both adult and juvenile crabs tolerated recruits. Adult crabs behaved indifferently towards juvenile crabs, sometimes tolerating them, sometimes expelling them. Recruits never showed agonistic behaviour among themselves. The agonistic interactions observed in the laboratory and the uniform population distribution pattern on sea anemones recently described for A. spinifrons indicate that this species exhibits territorial behaviour, which develops during ontogeny. Territoriality in this species and other symbiotic decapods may function as a density-dependent mechanism of population regulation, being mediated by the availability of hosts. Resource monopolisation behaviours may be common among other symbiotic and free-living marine invertebrates inhabiting discrete habitats that represent a limiting resource.