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Mating patterns and reproductive success in the bushy-tailed woodrat (Neotoma cinerea), as revealed by DNA fingerprinting 总被引:1,自引:0,他引:1
The mating patterns and reproductive success of the bushy-tailed woodrat (Neotoma cinerea) were investigated over a 3-year period (1992–1994) using DNA fingerprinting. Paternity was determined by genetic analysis
of 58 juveniles of known maternity from 35 litters. Analysis of DNA fingerprints revealed that all offspring within a litter
were fathered by a single male; the statistical probability of detecting multiple males mating with a female was high, indicating
that multiple paternity would have been detected had it occurred. However, individual males did not father more than one litter
from a given female either within or between years. At least 75% of females and 57% of males successfully produced offspring
each year. The finding that all littermates are first-order relatives may contribute to the high level of female cooperation
in this species.
Received: 28 May 1997 / Accepted after revision: 22 March 1998 相似文献
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TIMOTHY J. SMYSER SCOTT A. JOHNSON L. KRISTEN PAGE CASSIE M. HUDSON OLIN E. RHODES JR. 《Conservation biology》2013,27(4):752-762
Translocations are an important tool for wildlife conservation, although progress in the field of reintroduction biology has been hindered by the ad hoc and opportunistic nature of many translocations. We used an experimental translocation to elucidate the role of raccoon roundworm (Baylisascaris procyonis) and inbreeding depression in the decline of the Allegheny woodrat (Neotoma magister), an endangered species. We translocated woodrats from genetically diverse populations in the core of the species range to 4 previously occupied sites (reintroductions) and 2 sites supporting genetically depauperate populations (reinforcements) in Indiana (U.S.A.). In 2 reintroduction sites and 1 reinforcement site, we distributed anthelmintic baits to passively deworm raccoons and reduce the risk of woodrat exposure to roundworms. The remaining sites served as controls. We used raccoon latrine surveys and fecal flotation to monitor temporal variability in roundworm prevalence and effect of treatment. We used live trapping and microsatellite genotyping to monitor the demographic and genetic response of translocated populations over the following 54 months. At the conclusion of the study, 4 of 6 translocations were successfully maintaining abundance through local recruitment. The distribution of anthelmintic baits reduced levels of roundworm contamination, but levels of contamination were also low in 2 of 3 control sites. Reintroductions failed at control sites, one of which was due to high roundworm exposure. The other failed control reintroduction was likely attributable to demographic stochasticity and limited reproductive potential following initial mortality within the first 4 months. In both control and treatment reinforcements, increases in both allelic richness and heterozygosity were accompanied by increases in abundance, which is suggestive of genetic rescue. Our results demonstrate that mitigation of roundworm exposure through the distribution of anthelmintic baits can facilitate woodrat recovery and that diversity within genetically depauperate populations can be restored through the introduction of a limited number of individuals. El Uso de Reubicaciones Experimentales de Neotoma magister para Descifrar Agentes Causales de Disminución 相似文献
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R. S. Sikes 《Behavioral ecology and sociobiology》1996,38(5):303-310
The Trivers-Willard hypothesis of sex-biased maternal investment in response to fluctuations in resource availability has
provided a theoretical foundation for research on maternal investment for more than two decades. Their hypothesis holds that
mothers in poor condition as a result of poor resource availability should bias parental investment towards offspring with
the highest probability of reproducing. In the polygynous mating system of mammals where males compete for breeding access
to females, the hypothesis predicts investment favoring females. Although data from many systems have supported this hypothesis,
other systems do not follow the predicted patterns and have resulted in various alternative hypotheses. The present research
was designed to test whether differences in body condition of young reared by nutritionally stressed dams relative to young
reared by unstressed dams were maintained into adulthood, one of the fundamental assumptions underlying the Trivers-Willard
hypothesis. Post-weaning growth in eastern woodrats (Neotoma floridana) and northern grasshopper mice (Onychomys leucogaster) was examined relative to maternal nutritional plane. Individuals from undernourished dams were lighter than their unrestricted
counterparts at weaning but no difference was evident by the time they had reached adult size. Failure to maintain body condition
differences into adulthood violates one of the assumptions essential for application of the Trivers-Willard hypothesis of
maternal investment patterns. Although the Trivers-Willard model proposed that natural selection favors differential investment
in the sexes over the entire course of parental investment, evidence from this and other studies suggests that the Trivers-Willard
hypothesis might not be appropriate to address maternal investment questions in postnatally malnourished dams, but instead
should be restricted to systems concerned with prenatal maternal condition or resource availability.
Received: 22 February 1995/Accepted after revision: 30 December 1995 相似文献
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