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101.
Michael J. Lauer 《Behavioral ecology and sociobiology》1996,38(2):89-96
The resolution of intersexual conflict over mating should be dependent on the current state of each individual. In this study,
I used a factorial design to examine the influence of two physiological factors, sperm depletion and food deprivation, on
resistance to mating by females of the water strider, Aquarius remigis. Females employ several different mate-resisting tactics during an encounter with a male. Five measures of female resistance
to mating were identified: jumping, rolling, dunking, time spent dunking, and struggle duration. Jump, roll, and dunk rates
were highly correlated with each other and combined into one metric of resistance to mating (PC1) using principal components
analysis. Time per dunk (T/D) and struggle duration were also analyzed. Discrete male behaviors during the struggle could
not be identified. Two measures of female resistance, PC1 and T/D, were significantly lower in sperm-depleted females than
in sperm-replenished females. Struggle duration did not differ between the two treatments. Starvation had no effect on any
of the measures of resistance. Sperm depletion significantly enhanced the probability of mating (54% vs. 24% for replenished
females), while starvation had no effect on the probability of mating. I pooled all the females and compared females that
mated with those that did not mate. Nonmating females resisted significantly more than mating females in all three measures
of resistance. Path analysis indicated that PC1 was the only measure of resistance that was significantly negatively related
to the probability of mating. Almost half (46%) of sperm-depleted females showed no resistance to males, while only 3% of
sperm-replenished females were nonresistant. When nonresisters were removed from the analysis, sperm depletion had no effect
on any of the measures of female resistance to mating and no effect on the probability of mating. In A. remigis, female resistance appears to be a yes/no phenomenon with respect to sperm depletion and not affected directly by starvation.
Received: 2 September 1994/Accepted after revision: 9 September 1995 相似文献
102.
Brady A. Porter Anthony C. Fiumera John C. Avise 《Behavioral ecology and sociobiology》2002,51(4):350-359
In a variety of fish species with paternal care of offspring, females prefer to spawn in nests that already contain eggs.
This female preference has been hypothesized to explain egg thievery in male sticklebacks, allopaternal care of eggs in minnows,
and the evolution of egg-mimicking body features in male cichlids and darters. Here we employ microsatellite-based parentage
analyses to evaluate the reproductive success of striped darter (Etheostoma virgatum) males that appear to utilize two of these functionally related tactics to entice females to spawn in their nests. In an
isolated population (Clear Creek, Ky.), we observed that breeding males develop conspicuous white spots on their pectoral
fins. If these spots are egg mimics, as we suspect, then this represents the fourth independent evolutionary origin of egg
mimicry documented to date in darters, the first based on pigmentation (as opposed to physical structures), and the first
in which the egg mimics vary greatly in number among males. From direct counts of microsatellite genotypes in clutches of
embryos, at least 3.8 females contributed to the progeny within a typical nest, and females tended to spawn preferentially
with males that were larger and displayed more egg-mimic spots. In another population (Hurricane Creek, Tenn.) without egg
mimics, the multi-locus genetic data document that allopaternal care is common, especially among the smallest males who sometimes
tend nests containing their own as well as an earlier sire's offspring. Thus, these foster males had adopted egg-containing
nests and then successfully spawned with subsequent females. Overall, the genetic data on paternity and maternity, in conjunction
with field observations, suggest that egg mimicry and allopaternal care are two mate-attracting reproductive tactics employed
by striped darter males to exploit female preferences for spawning in nests with 'eggs'.
Electronic Publication 相似文献
103.
Dickens JC 《Die Naturwissenschaften》2007,94(10):847-852
Chemical signals emitted by insects and their hosts are important for sexual communication and host selection. Plant volatiles
facilitate the location of suitable hosts for feeding and oviposition, and may moderate responses to sex and aggregation pheromones.
While mating has been shown to moderate behavioral responses to pheromones in a number of insects, little is known about the
effects of mating on behavioral responses of insects to plant attractants, and even less is known about the mechanisms involved.
In this study, mating was shown to decrease behavioral responses of the Colorado potato beetle to a host kairomone within
24 h, and attraction to the kairomone recovers only after 72 h. This decrease in responsiveness also occurs when only contact
with the opposite sex is allowed; the effect is not observed with contact among individuals of the same sex. Peripheral olfactory
responses to a component of the kairomone correlate with the observed behavioral responses and suggest involvement of antennal
receptors in the behavioral change. 相似文献
104.
M. J. Freake 《Behavioral ecology and sociobiology》1998,43(4-5):339-344
Sleepy lizards are monogamous skinks which show high pair fidelity. This study reveals inter- and intrasexual differences
in homeward orientation performance in this lizard. Male and female lizards were displaced during three phases of the spring
activity period, the pre-pairing, pairing/mating, and post-pairing periods. All groups (with the exception of post-pairing
males) were significantly oriented homewards, but males were significantly better oriented towards home than females during
the pairing period. Furthermore, males were significantly better homeward oriented during the pre-pairing and pairing periods
than in the post-pairing period. Similar results were observed for rate of movement away from the release site. In sleepy
lizards, sex-based differences in homing behaviour are unlikely to be attributable to differences in the area of familiarity,
or availability of orientation mechanisms. However differences in homing motivation may explain these differences. Males may
miss mating if absent from the home range during the pre-pairing and pairing periods, while females may still be able to obtain
a mating even when absent. Females however may be more motivated than males to return to the familiar home range during the
post-pairing period to ensure efficient feeding during internal embryo development.
Received: 16 February 1998 / Accepted after revision: 28 March 1998 相似文献
105.
Dina K. N. Dechmann Elisabeth K. V. Kalko Gerald Kerth 《Behavioral ecology and sociobiology》2007,61(8):1219-1228
In polygynous mammals, males are usually responsible for gene flow while females are predominantly philopatric. However, there
is evidence that in a few mammalian species female offspring may disperse to avoid breeding with their father when male tenure
exceeds female age at maturity. We investigated offspring dispersal and local population structure in the Neotropical bat
Lophostoma silvicolum. The mating system of this species is resource defense polygyny, with the resource being active termite nests, excavated
by single males, which are then joined by females. We combined field observations of 14 harems during 3 years and data about
the genetic structure within and between these groups, calculated with one mitochondrial locus and nine nuclear microsatellite
loci. The results show that both male and female offspring disperse before maturity. In addition, we estimated life span of
excavated termite nests and the duration they were occupied by the same male. Our findings suggest that long male tenure of
up to 30 months is indeed a likely cause for the observed dispersal by female offspring that can reach maturity at a low age
of 6 months. We suggest that dispersal by offspring of both sexes may occur quite frequently in polygynous tropical bats and
thus generally may be more common in mammals than previously assumed. 相似文献
106.
O. Anne E. Rasa 《Behavioral ecology and sociobiology》1998,43(2):105-113
Parastizopus armaticeps is a nocturnal subsocial detritivorous desert tenebrionid that produces very few offspring per brood. The two environmental
factors that constrain reproduction, rapid sand desiccation rate and food scarcity, are countered by biparental effort. Males
dig and extend breeding burrows, maintaining their moisture level; females forage on the surface at night for high-quality
detritus, the larval food. This was shown to be a scarce and unpredictable resource for which there is high competition. When
food was supplemented in a field experiment, offspring number and survivorship doubled and burrow failure due to desiccation
dropped from approximately half, the typical failure rate for unsupplemented burrows, to zero. Food supplementation did not,
however, increase larval foodstore size and there was no difference in the size of the offspring produced. Supplemented females
reallocated their time, foraging less and digging more with the male. This change in maternal behaviour patterns resulted
in deeper burrows which remained moist longer, thus extending the larval production period. Female foraging efficiency, particularly
food retrieval speed, determined how much time females could allocate to digging, consequently increasing the reproductive
success of the pair. Burrow depth and sand moisture level at the burrow base were the major correlates of reproductive success,
but the scarcity and unpredictability of high-quality food on the surface and the competition for this resource influenced
the number of offspring indirectly through their effect on female behaviour.
Received: 29 November 1996 / Accepted after revision: 7 December 1997 相似文献
107.
Operational sex ratio versus gender density as determinants of copulation duration in the walnut fly,Rhagoletis juglandis (Diptera: Tephritidae) 总被引:5,自引:0,他引:5
In laboratory and field studies of the walnut fly, Rhagoletis juglandis Cresson (Diptera: Tephritidae), we assessed the effect of operational sex ratio on copulation duration and partitioned the
sex ratio effect into component effects due to male density and female density. In our first laboratory experiment, results
were clearly consistent with theoretical expectation: increases in male density were associated with significant increases
in copulation duration while increases in female density were associated with significant decreases in copulation duration.
These component effects yielded a striking composite effect of operational sex ratio (OSR) on copulation duration in which
male-biased ratios were associated with low frequencies of short copulations and female-biased ratios were associated with
high frequencies of short copulations. Consistent with a priori expectations concerning costs of territorial behavior, the
effect of male density on copulation duration was stronger than that of female density. There was no significant interaction
between the effects of gender density on copulation duration: each gender density contributed additively to the composite
OSR effect on copulation duration. In contrast to the effect of OSR, overall density had little effect. Field data corroborated
these findings fully and showed additionally that OSR in the vicinity of fruit tended in nature to be male-biased. In a second
laboratory experiment, we measured copulation duration for individuals exposed alternately to male-biased and female-biased
ratios. Individual flies consistently copulated for longer in male-biased environments than in female-biased ones. We propose
that this plasticity permits individuals to track changes in local sex ratio over space and time and respond appropriately.
Received: 15 November 1995/Accepted after revision: 27 April 1996 相似文献
108.
M. Polak Larry L. Wolf William T. Starmer J. S. F. Barker 《Behavioral ecology and sociobiology》2001,49(2-3):196-205
The mating plug in Drosophila hibisci Bock is a firm, gelatinous structure that forms within the female’s uterus during copulation. Two non-mutually exclusive
hypotheses for the function of the plug were evaluated. The plug may serve as a nutritional gift that females digest, using
the constituents for somatic maintenance or to provision eggs as they mature within the ovaries. Alternatively, the plug may
act as a chastity enforcement device by preventing subsequent copulations, and thereby reducing sperm competition. Plug size
did not decrease within females over a period of 2 days, and dietary treatment in females did not affect plug size. The extent
of ovarian provisioning was also not related to plug size. These results weaken the nutritional gift hypothesis. In contrast,
the probability of a second copulation increased sharply with an experimental decrease in plug size. Moreover, females with
plugs experimentally reduced in size were courted significantly more and mated significantly faster than females with larger
plugs. These results support the chastity enforcement hypothesis. The plug retains the ejaculate and concentrates sperm at
the anterior end of the uterus near the apertures of the sperm storage organs. The presence of the plug thus probably facilitates
the movement of sperm into storage by retaining sperm at the anterior end of the uterus near the apertures of the sperm storage
organs, which may be especially important for D. hibisci, in which sperm length is nearly twofold greater than ventral receptacle length. Matings with newly eclosed virgin females
were significantly shorter than with older virgins, and copulations with the younger virgins ended more often without any
sperm having yet entered into storage. The effectiveness of the plug in safeguarding a male’s ejaculate may have favoured
the evolution of shortened copula durations with young virgins. One fitness advantage of shortened copula duration could be
time liberated for the pursuit of further mating opportunities.
Received: 12 May 2000 / Revised: 22 September 2000 / Accepted: 15 October 2000 相似文献
109.
Mating strategies and mating success of fallow (Dama dama) bucks in a non-lekking population 总被引:2,自引:0,他引:2
N. P. Moore P. F. Kelly J. P. Cahill T. J. Hayden 《Behavioral ecology and sociobiology》1995,36(2):91-100
The rutting behaviour of bucks in an enclosed population was investigated between 1988 and 1990. A substantial proportion of the matings were observed. After preliminary observations in the 1987 rut we categorised bucks into one of four rutting strategies based mainly on their degree of territoriality. We investigate the effects of age, dominance and mating strategy on mating success. Territories were aggregated in an area of oak woods and mating success was highly skewed. Bucks of between 5 and 7 years old achieved the majority (over 90%) of observed matings. Mating success was highly correlated with dominance but only weakly related to fighting success. The possession of a territory was crucial to achieving high reproductive success, with a 38-fold difference between the most and least successful strategies. Bucks pursuing the different strategies also differed in the time they commenced groaning, timing of matings, mating interference and the locations where they achieved their matings. Although high-ranking males devoted considerable effort to obtaining and defending a territory only 36% of each buck's matings were achieved on his territory and males tended to abandon these sites when the tendency of females to visit them decreased. 相似文献
110.
Random denominators and the analysis of ratio data 总被引:2,自引:0,他引:2
Liermann Martin Steel Ashley Rosing Michael Guttorp Peter 《Environmental and Ecological Statistics》2004,11(1):55-71
Ratio data, observations in which one random value is divided by another random value, present unique analytical challenges. The best statistical technique varies depending on the unit on which the inference is based. We present three environmental case studies where ratios are used to compare two groups, and we provide three parametric models from which to simulate ratio data. The models describe situations in which (1) the numerator variance and mean are proportional to the denominator, (2) the numerator mean is proportional to the denominator but its variance is proportional to a quadratic function of the denominator and (3) the numerator and denominator are independent. We compared standard approaches for drawing inference about differences between two distributions of ratios: t-tests, t-tests with transformations, permutation tests, the Wilcoxon rank test, and ANCOVA-based tests. Comparisons between tests were based both on achieving the specified alpha-level and on statistical power. The tests performed comparably with a few notable exceptions. We developed simple guidelines for choosing a test based on the unit of inference and relationship between the numerator and denominator. 相似文献