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1.
Spontaneous responses to the scent marks of male Saguinus fuscicolliswere tested in experiments where the subjects received a choicebetween scent of intact males and castrated males. Male tamarinsdiscriminated between the odors of intact and castrated males,both on the basis of fresh individual scent marks and on thebasis of marks from several donors pooled in methanol. Theirdiscriminatory response to pooled odors was more pronouncedthan that to individual odors. Females discriminated betweenintact and castrated male scents only on the basis of pooledsamples. This result shows that castration causes changes inthe odor of males. The difference in the response of the tamarinsto individual scent marks as compared to pooled samples is discussedin terms of quantitative changes caused by extraction and ofindividual recognition. 相似文献
2.
Sylvie Dandieu Cécile Rahuel Jacques Ruffié Gérard Lucotte 《Biochemical Systematics and Ecology》1984,12(2):237-244
Highly repeated DNA sequences from man, five other primate species and rat were compared using five restriction endonucleases. Calculations of a similarity index based on the mobility of various bands indicate that man, chimpanzee and baboons are very similar. The sequences of the genomes studied have apparently been reorganized during primate evolution. 相似文献
3.
4.
This study is an exercise to check the efficiency of the existing reserve system, and to show how systematic conservation
planning—using information available and the complementarity concept—can improve the basis for decisions and minimize costs.
We verified the performance, in number of cells and primate species representation, of the existing Atlantic Forest (Brazil)
reserve network with a quarter-degree resolution grid, with 1,884 cells. We used occurrence data of 20 endemic primate species,
and the maps of 237 existing reserves. Reserve networks were selected to represent primate species first considering no pre-existing
reserves in Atlantic Forest, and then, considering the existing reserve system, taking into account the minimum area for viable
population of the larger species (Northern muriqui Brachyteles hypoxanthus). Reserve selection was carried out using the complementarity concept implemented by a simulated annealing algorithm. Primate
species representation (at least one occurrence in the network) could be achieved with 8% of the existing reserve system (nine
cells in relation to the 120 in the existing reserve system). We found that today’s reserve system represents 89% of endemic
primate species, excluding the species Coimbra Filho’s titi monkey (Callicebus coimbrai) and Marcgraf’s capuchin (Cebus flavius). The networks selected without considering existing reserves contained nine cells. The networks selected considering existing
reserves (120 cells), had two new cells necessary to represent all the primates. This does not mean that a viable alternative
is to start from zero (i.e., nonexistent reserves). Identifying critical supplementary areas using biodiversity information
to fill the gaps and then starting “conservation in practice” in these areas should be priorities. 相似文献
5.
《Chronobiology international》2013,30(3):165-170
Groups of photosensitive, unstimulated or stimulated, male blackheaded buntings were subjected to photoregimes of 15 hr of green light of three intensities and 9 hr of dark per day. In some groups green light was interrupted with 90 min of bright fluorescent light at different times in the subjective day. While gonads did not develop or regressed in some groups, birds in others behaved as if exposed to long daylengths. The results besides suggesting the involvement of endogenous circadian rhythm during initiation and maintenance of gonadal growth indicate that the reproductive rhythms are entrained and induced by environmental photoperiod. 相似文献
6.
We examined the terminations of sensory afferents in the brainstem and spinal cord of squirrel monkeys and prosimian galagos 4-8 years after a therapeutic forelimb or hindlimb amputation within 2 months of birth. In each animal, the distributions of labeled sensory afferent terminations from remaining body parts proximal to the limb stump were much more extensive than in normal animals. These sprouted afferents extended into the portions of the dorsal horn of the spinal cord as well as the cuneate and external cuneate nuclei of the brainstem (forelimb amputees) or spinal Clarke's column (hindlimb amputee) related to the amputated limb. Such reorganization in sensory afferents along with reorganization of the motor efferents to muscles (Wu and Kaas, J Neurosci 19 : 7679-7697, 1999, Neuron 28 : 967-978, 2000) may provide a basis for mislocated phantom sensations of missing forelimb movements accompanying actual shoulder movements during cortical stimulation or movement imagery in patients with amputations. 相似文献
7.
Microcebus ravelobensis is an endangered nocturnal primate endemic to northwestern Madagascar. This part of the island is subject to extensive human
intervention leading to massive habitat destruction and fragmentation. We investigated the degree of genetic differentiation
among remaining populations using mitochondrial control region sequences (479–482 bases). Nine populations were sampled from
the hypothesized geographic range. The region is composed of three inter-river systems (IRSs). Samples were collected in three
areas of continuous forests (CFs) and six isolated forest fragments (IFFs) of different sizes. We identified 27 haplotypes
in 114 animals, with CFs and IFFs harbouring 5–6 and 1–3 haplotypes, respectively. All IFFs were significantly differentiated
from each other with high ΦST values and sets of unique haplotypes. The rivers constitute significant dispersal barriers with over 82% of the molecular
variation being attributed to the divergence among the IRSs. The data suggest a deep and so far unknown split within the rufous
mouse lemurs of northwestern Madagascar. The limited data base and the lack of ecological and morphological data do not allow
definite taxonomic classification at this stage. However, the results clearly indicate that M.
ravelobensis consists of three evolutionary significant units, possibly cryptic species, which warrant urgent and separate conservation
efforts. 相似文献
8.
Geometric morphometric studies are increasingly becoming common in systematics and palaeontology. The samples in such studies
are often small, due to the paucity of material available for analysis. However, very few studies have tried to assess the
impact of sampling error on analytical results. Here, this issue is addressed empirically using repeated randomized selection
experiments to build progressively smaller samples from an original dataset of ∼400 vervet monkey (Cercopithecus aethiops) skulls. Size and shape parameters (including mean size and shape, size and shape variances, angles of allometric trajectories)
that are commonly used in geometric morphometric studies, are estimated first in the original sample and then in the random
subsamples. Estimates are then compared to give an indication of what is the minimum desirable sample size for each parameter.
Mean size, standard deviation of size and variance of shape are found to be fairly accurate even in relatively small samples.
In contrast, mean shapes and angles between static allometric trajectories are strongly affected by sampling error. If confirmed
in other groups, our findings may have substantial implications for studies of morphological variation in present and fossil
species. By performing rarefaction analyses like those presented in our study, morphometricians can be easily provided with
important clues on how a simple but crucial factor like sample size can alter results of their studies. 相似文献
9.
W. W. Socha J. Moor-Jankowski A. S. Wiener D. R. Risser H. Plonski 《American journal of physical anthropology》1976,45(3):485-491
The human-type A-B-O blood groups of 52 bonnet macaques (Macaca radiata) were determined. Application of method of population genetics indicated the gene frequences to be O = 0.173, A = 0.480 and B = 0.347. Cross testing of sera and red cells of the bonnet macaques revealed two blood-type-specific isoagglutinins, one of them strong enough for use as a blood typing reagent. No blood group polymorphism was revealed by testing bonnet macaque red cells with isoantisera produced in rhesus monkeys (M. mulatta) and in crab-eating macaques (M. fascicularis). The rhesus and crab-eating macaque isoantisera reacted either with all or with none of the bonnet macaque red cells tested. 相似文献
10.
B. Ehinger 《Cell and tissue research》1971,116(2):157-177
Summary The distribution of adrenergic terminals to the anterior eye segment of humans, Cynomolgue monkeys, squirrel monkeys, owl monkeys, Cebus monkeys, vervets, tamarins, and baboons has been investigated. The cornea is normally devoid of adrenergic terminals, except in a plexus near the limbus. The trabecular meshwork contains varying numbers of adrenergic terminals: usually none in Cynomolgus monkeys, patas monkeys, vervets, and humans, although fibres have very rarely been observed in Cynomolgus monkeys, vervets, and humans; a few in owl monkeys, squirrel monkeys, and tamarins; and moderate numbers in Cebus monkeys and baboons. From the evidence, however, it seems premature to presume an adrenergic innervation of the trabecular mechanism regulating the outflow resistance. The dilatator pupillae is regularly supplied with numerous adrenergic terminals and in the iris stroma there is probably an adrenergic innervation of the melanophores. The sphincter pupillae regularly contains adrenergic terminals with notable species differences; most fibres occur in baboons and fewest in humans, with the remaining species forming a middle class. The ciliary processes in all species contain a moderate number of adrenergic terminals, presumably primarily associated with the epithelium. Intraepithelial adrenergic terminals have been observed on the pars plana of the ciliary body of humans, Cebus monkeys, vervets, baboons, and patas monkeys. The ciliary muscle of baboons and Cynomolgus monkeys contains numerous adrenergic terminals. Moderate numbers occur in Cebus monkeys and vervets, and still less in (in falling order) tamarins, squirrel monkeys, humans, and patas monkeys. 相似文献