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1.
Play behavior and stress-associated behavior of a captive juvenile gorilla were observed before and after his transfer to a larger and more natural environment. The gorilla was observed for 4 months after the transfer and at 1 and 4 years after the transfer. Throughout his first month in the new environment play decreased dramatically. Although play subsequently increased again 2 months and 1 year after the transfer, it never reached the levels of play in the old environment. Four years after the move his play had decreased again to the low level of his first month in the new environment. Two of his stress-associated behaviors, coprophagy and regurgitation/reingestion, decreased after the transfer. Self-clasping behavior increased initially in the new environment and remained at high levels 1 year after the move. Four years after the move his self-clasping behavior was significantly less than at 1 year after the move; however, it continued to be significantly greater than in the old environment. These findings suggest that larger and more natural environments do not necessarily result in more play activity or a reduction in all stress-associated behavior. 相似文献
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Additional Restriction Endonuclease Cleavage Sites on the Bacteriophage P22 Genome 总被引:7,自引:0,他引:7 下载免费PDF全文
We present complete restriction endonuclease cleavage site maps of the bacteriophage P22 chromosome for 16 enzymes with six base recognition sequences, thereby positioning 116 new sites on the chromosome. Twenty-four such restriction maps for P22 DNA, containing 162 sites, have now been completed, and three enzymes were found that did not cut P22 DNA. Our results are consistent with the ideas that ClaI does not cleave the methylated recognition sequence ATCGA(me)T or A(me)TCGAT and StuI does not cleave the methylated recognition sequence AGGCC(me)T. 相似文献
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Dispersal by young mammals away from their natal site is generallythought to reduce inbreeding, with its attendant negative fitnessconsequences. Genetic data from the dwarf mongoose, a pack-livingcarnivore common in African savannas, indicate that there areexceptions to this generalization. In dwarf mongoose populationsin the Serengeti National Park, Tanzania, breeding pairs arecommonly related, and close inbreeding has no measurable effecton offspring production or adult survival. Inbreeding occursbecause average relatedness among potential mates within a packis high, because mating patterns within the pack are randomwith respect to the relatedness of mates, and because dispersaldoes little to decrease the relatedness among mates. Young femalesare more likely to leave a pack when the dominant male is aclose relative but are relatively infrequent dispersers. Youngmales emigrate at random with respect to the relatedness ofthe dominant female and tend to disperse to packs that containgenetically similar individuals.[Behav Ecol 7: 480489(1996)] 相似文献
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Failures of reproductive suppression in dwarf mongooses (Helogale parvula): accident or adaptation? 总被引:1,自引:0,他引:1
In many communally breeding species, only the dominant femalenormally breeds, while subordinates tolerate reproductive suppression(these are "despotic" species, in the terminology of Brown,1987; Macdonald and Moehlman, 1983; Vehrencamp, 1983). Yet inmany species for which reproductive suppression is the norm(across a wide variety of taxa), subordinates do occasionallybreed. Because reproduction by subordinates is atypical forthese species, it is often regarded as simple failure of thenormal mechanisms of suppression. An alternate hypothesis isthat subordinate pregnancies represent an evolutionary compromisebetween dominant and subordinate, in which dominants concedetheir monopoly on reproduction in order to retain helpers. Weuse data from a long-term study of dwarf mongooses (Helogaleparvula) in Serengeti National Park, Tanzania, to test thishypothesis, using an inclusive fitness model adapted from oneby Vehrencamp (1983). We find that the incidence of subordinatepregnancy closely matches that predicted by the model, suggestingthat the mechanisms that underlie reproductive suppression indwarf mongooses are finely adjusted to the social and demographicenvironment. [Behav Ecol 1991; 2: 715] 相似文献
6.
Mutation analysis of the cystic fibrosis transmembrane regulator gene in native American populations of the southwest 下载免费PDF全文
Theresa A. Grebe Winifred W. Doane Sarah F. Richter Carol Clericuzio R. A. Norman William K. Seltzer Susan N. Rhodes Bruce E. Goldberg Lucy S. Hernried Melody McClure Gail Kaplan 《American journal of human genetics》1992,51(4):736-740
We report DNA and clinical analyses of cystic fibrosis (CF) in two previously unstudied, genetically isolated populations: Pueblo and Navajo Native Americans. Direct mutation analysis of six mutations of the CFTR gene--namely, delta F508, G542X, G551D, R553X, N1303K, and W1282X--was performed on PCR-amplified genomic DNA extracted from blood samples. Haplotype analyses with marker/enzyme pairs XV2c/TaqI and KM19/PstI were performed as well. Of the 12 affected individuals studied, no delta F508 mutation was detected; only one G542X mutation was found. None of the other mutations was detected. All affected individuals have either an AA, AC, or CC haplotype, except for the one carrying the G542X mutation, who has the haplotype AB. Clinically, six of the affected individuals examined exhibit growth deficiency, and five (all from the Zuni Pueblo) have a severe CF phenotype. Four of the six Zunis with CF are also microcephalic, a finding not previously noted in CF patients. Our DNA data have serious implications for risk assessment of CF carrier status for these people. 相似文献
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Estimates of population size are critical for conservation and management, but accurate estimates are difficult to obtain for many species. Noninvasive genetic methods are increasingly used to estimate population size, particularly in elusive species such as large carnivores, which are difficult to count by most other methods. In most such studies, genotypes are treated simply as unique individual identifiers. Here, we develop a new estimator of population size based on pedigree reconstruction. The estimator accounts for individuals that were directly sampled, individuals that were not sampled but whose genotype could be inferred by pedigree reconstruction, and individuals that were not detected by either of these methods. Monte Carlo simulations show that the population estimate is unbiased and precise if sampling is of sufficient intensity and duration. Simulations also identified sampling conditions that can cause the method to overestimate or underestimate true population size; we present and discuss methods to correct these potential biases. The method detected 2–21% more individuals than were directly sampled across a broad range of simulated sampling schemes. Genotypes are more than unique identifiers, and the information about relationships in a set of genotypes can improve estimates of population size. 相似文献
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Gary G. Bennett Dori M. Steinberg Michele G. Lanpher Sandy Askew Ilana B. Lane Erica L. Levine Melody S. Goodman Perry B. Foley 《PloS one》2013,8(8)