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901.
Debra S. Judge 《Human nature (Hawthorne, N.Y.)》1995,6(4):291-323
Sex differences in behavior are most interesting when they are the result of inherent differences in the operational rules
motivating behavior and not merely a reflection of differing life history experiences. American men and women exhibit a few
differences in testamentary patterns of property allocation that appear to be due to inherently different rules of allocation.
Even when analyses control for resources and surviving kin configurations, women distribute their property among a greater
number of individual beneficiaries than do men. The most striking differences in property allocation between men and women
occur within the nuclear family and reflect differences in reproductive life span and the resulting reproductive conflicts
between spouses that can endure beyond death.
The initial research for this paper was funded by a grant to Sarah Blaffer Hrdy and the author from the Rockefeller Foundation
Program in Changing Gender Roles.
Debra Judge is associated with the Ecology Graduate Group and the Department of Anthropology at the University of California
at Davis. Her interests focus on human demography, reproductive strategies, and the ecological conditions influencing human
mating and parenting strategies—especially intergenerational resource transfer. 相似文献
902.
《Journal for Nature Conservation》2014,22(5):405-412
Translocation, or the purposeful movement of organisms from one location to another for conservation, is currently being used to bolster populations of the endangered greater prairie-chicken (Tympanuchus cupido). We used radiotelemetry to compare survival between 58 resident birds and 54 newly translocated greater prairie-chickens that were sourced from a location more than 325 km away. Model averaged survival estimates were lower in translocated birds (0.42; 95% CI: 0.17–0.66) than in resident prairie-chickens (0.65; 95% CI: 0.46–0.79) through the breeding season. Habitat, sex and year were each included in at least 1 of the top 4 models, but the model averaged confidence intervals for each parameter encompassed zero. Survival of both resident and translocated prairie-chickens increased throughout the breeding season. Both translocated and resident prairie-chickens selected for core prairie habitat over agriculture, and birds tended to avoid surrounding private grasslands and wooded areas. We suggest that future translocation projects account for reduced survival of translocated birds when determining the appropriate release cohort sizes and sex ratios. We also recommend that future management for greater prairie-chicken habitat focus on the expansion of core protected patches of prairie to promote elevated survival and better chances of conservation success. 相似文献
903.
A. Yamauchi 《Journal of Ethology》2000,18(2):115-121
A mathematical model is proposed to explain energy resource allocation between sperm production and territoriality in male
reef fishes (Labridae species) from the point of view of optimization. Labridae species are typically characterized by both
TP (terminal phase) and IP (initial phase) males. The former are considered to release a lower amount of sperm but show aggressive
territoriality. In the model, TP male reproductive success is considered as depending upon both fertilization probability
(depending on sperm density) and the individual's own territorial activities. Between these factors, a trade-off exists by
which the fertilization probability can be enhanced only by reducing territoriality. Therefore, the male has to decide how
much of the total available energy resource should be allocated to each. The model showed that under high fertilization efficiency
the male can achieve high success by spending less of the resource on sperm production and correspondingly more for territoriality.
The TP male reproductive success increases with decreasing male density in the habitat. Nevertheless, when intruding males
cannot be excluded completely by territorial behavior of the TP male, females prefer high male density. If females can control
the number of intruding males to some degree, conflict may arise between the sexes.
Received: December 8, 1999 / Accepted: May 24, 2000 相似文献
904.
Larry A. Greenberg 《Environmental Biology of Fishes》1991,31(4):389-401
Synopsis The densities, habitat use, and feeding behaviors of 13 fish species belonging to the benthic invertebrate-feeding guild were studied by snorkeling at three localities in the Little River of eastern Tennessee, U.S.A. Resource partitioning occurred by habitat, feeding behavior and time of activity. Differences were also found at the generic level.Cottus was a nocturnal feeder, whereasPercina andEtheostoma were, for the most part, diurnally active.Percina moved about rapidly and spent most of its time above the bottom. In contrast,Etheostoma varied considerably in the amount of time spent under cover, spent little time above the bottom, and exhibited low levels of swimming activity. Nearly all species sought cover at night, suggesting they may be particularly sensitive to predation at night. Species with small adult sizes (Etheostoma, Cottus andP. evides) were concentrated in shallow water habitats, whereas species with large adult sizes (Percina) were more abundant in deep water habitats. The habitat use data are consistent with the hypothesis that size-selective predation by centrarchid bass may cause smaller fish to avoid deep water areas. Large species should have a lower risk of predation due to their size and behavior. 相似文献