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Roman M. Wittig Catherine Crockford Robert M. Seyfarth Dorothy L. Cheney 《Behavioral ecology and sociobiology》2007,61(6):899-909
Theory predicts that females in species with matrilineal dominance hierarchies should use nepotistic support systems to maintain
their family’s rank. Female Old World monkeys, however, form alliances against other females at surprisingly low rates. Nonetheless,
in many species, females utter threat vocalizations when observing others’ disputes, suggesting that these vocalizations may
function as ‘vocal alliances’. We describe a playback experiment testing the efficacy of vocal alliances in free-ranging female
baboons. Subjects were played the same female’s threat-grunts under three separate conditions: after being threatened by the
signaller’s close relative to mimic kin support, after being threatened by a female maternally unrelated to the signaller
to mimic non-kin support, and after a friendly interaction with the signaller’s close relative as a control. Subjects responded
more strongly to the playback and avoided the signaller and her matrilineal relatives for a longer period of time in kin support
trials than in either non-kin support or no aggression trials. In contrast, there was no difference in subjects’ behaviour
between non-kin support and no aggression trials. These results corroborate observational data showing that vocal support
occurs at a higher rate than physical support in female baboons, and that kin are more likely to provide vocal support than
non-kin. We conclude that vocal support plays a similar role as physical support in the alliances of female baboons. 相似文献
3.
Maternal investment in rhesus macaques (Macaca mulatta): reproductive costs and consequences of raising sons 总被引:1,自引:0,他引:1
Maternal investment in offspring is expected to vary according to offspring sex when the reproductive success of the progeny
is a function of differential levels of parental expenditure. We conducted a longitudinal investigation of rhesus macaques
to determine whether variation in male progeny production, measured with both DNA fingerprinting and short tandem repeat marker
typing, could be traced back to patterns of maternal investment. Males weigh significantly more than females at birth, despite
an absence of sex differences in gestation length. Size dimorphism increases during infancy, with maternal rank associated
with son’s, but not daughter’s, weight at the end of the period of maternal investment. Son’s, but not daughter’s, weight
at 1 year of age is significantly correlated with adult weight, and male, but not female, weight accounts for a portion of
the variance in reproductive success. Variance in annual offspring output was three- to fourfold higher in males than in females.
We suggest that energetic costs of rearing sons could be buffered by fetal delivery of testosterone to the mother, which is
aromatized to estrogen and fosters fat accumulation during gestation. We conclude that maternal investment is only slightly
greater in sons than in daughters, with mothers endowing sons with extra resources because son, but not daughter, mass has
ramifications for offspring sirehood. However, male reproductive tactics supersede maternal investment patterns as fundamental
regulators of male fitness.
Received: 23 July 1999 / Received in revised form: 23 February 2000 / Accepted: 13 March 2000 相似文献
4.
Chaoyang DU Jingjie YU Huaping ZHONG Dandan WANG 《Frontiers of Environmental Science & Engineering》2015,9(2):288
There is no alternative to the world’s water resources, and their increasing scarcity is making it difficult to meet the world population’s water needs. This paper presents a sustainable water resources system (SWRS) and analyzes the operating mechanism that makes it possible to evaluate the status of such a system. A SWRS can be described as a complex coupling system that integrates water resources, social, economic and ecological systems into a whole. The SWRS’s operating mechanism is composed of dynamic, resistance and coordination components, and it interacts with and controls the system’s evolution process. The study introduces a new approach, set pair analysis theory, to measure the state of a SWRS, and an evaluation index system is established using the subsystems and operating mechanism of a SWRS. The evaluation index system is separated into three levels (goal level, criteria level and index level) and divides the index standard into five grades. An evaluation model of the SWRS based on set pair analysis theory is constructed, and an example of SWRS evaluation in Shanghai is presented. The connection degrees of the index in the three levels are calculated, and the connection degree of the goal index is calculated to be 0.342, which classifies the city’s SWRS condition as grade 2. The sustainable use of water resources in the region is determined to be at a relatively adequate level that meets the requirements of sustainable development. 相似文献
5.
B. H. King 《Behavioral ecology and sociobiology》2000,48(4):316-320
In the parasitoid wasp Spalangia endius more offspring and a greater proportion of daughters were oviposited in, and emerged from 0-day-old versus 3-day-old hosts.
Offspring that developed on the younger hosts (1) were larger at adulthood, (2) developed more quickly, (3) had higher survivorship
to adulthood, and (4) were more often able to chew their way out of the host. Sons and daughters did not differ in how host
age affected their size, development rate, or survivorship. The greater proportion of daughters from the younger hosts may
be adaptive, as described by the host quality model (a variant of the Trivers and Willard hypothesis). It is adaptive if greater
size or more rapid development has a more positive effect on a daughter’s than a son’s fitness and the positive effect is
large enough to compensate for sons being trapped disproportionately to daughters in the older hosts. Despite greater success
at drilling the younger hosts, mothers did not try to drill them sooner or more often. Having previously oviposited on the
older rather than the younger hosts had no detrimental effect on the mother’s subsequent longevity or offspring production.
Received: 8 March 2000 / Revised: 9 June 2000 / Accepted: 24 June 2000 相似文献
6.
Cassiduloids are currently rare irregular echinoids with a highly conserved adult morphology. Aristotle’s lantern is present
only during the post-metamorphic stage, and little is known about the early development of species in this group. Cassidulus mitis produces eggs of about 375 μm in diameter, lecithotrophic larvae with four reduced arms with skeletal fenestrated rods, cilia
along the body surface, and a ciliated band on arms and lobes. Offspring is brooded among the female spines from embryo to
settler’s stage. The echinopluteus larval stage is reached 6 days after fertilization, and the settler’s stage is formed at
the age of 17 days. Aristotle’s lantern appears around the thirteenth day of development. The lantern is well developed and
functional in settlers. It remains until at least 62 days after fertilization and can be used to acquire food from the environment.
The early development of C. mitis is unusual concerning features of typical lecithotrophic larvae (such as reduced arms), but retains some features of planktotrophic
larvae (such as skeletal rods and a ciliated band). Regarding egg size, early development in C. mitis seems to be transitioning from facultative lecithotrophic to typical obligate lecithotrophic pattern in echinoid larval evolution. 相似文献
7.
Aaron Christ Jay Ver Hoef Dale L. Zimmerman 《Environmental and Ecological Statistics》2008,15(1):27-38
Wildlife biologists are often interested in how an animal uses space and the habitat resources within that space. We propose
a single model that estimates an animal’s home range and habitat selection parameters within that range while accounting for
the inherent autocorrelation in frequently sampled telemetry data. The model is applied to brown bear telemetry data in southeast
Alaska.
This article is based on a portion of this author’s Ph.D. dissertation completed in 2003 at the University of Iowa. 相似文献
8.
Animals’ contest performance is influenced by their recent contest experiences. This influence could either be exerted by
individuals re-estimating their own fighting ability (self-assessment) or by their opponents responding to status-related
cues (social-cue mechanism) or both. Individuals of Kryptolebias marmoratus, a hermaphroditic killifish, were given different contest experiences to examine how two opponents’ prior experiences combined
to determine their contest interaction and to test both of these mechanisms as potential causes of the observed experience
effect. Our data showed that losers’ decisions to retreat at different stages of a contest were influenced by their own but
not by the winners’ contest experience—a result consistent with self-assessment but not with the social-cue mechanism. An
association between the fish initiating and winning contests thus probably arose because both were correlated with an individual’s
assessment of its fighting ability, but not because initiating contests made opponents more inclined to retreat. 相似文献
9.
Mace R 《Behavioral ecology and sociobiology》1996,38(2):75-81
Demographic data from 848 Gabbra households are used to examine the relationships between herd size and reproductive success
in relation to sex, in a traditional, pastoralist population. The number of camels in the household herd has a significant
positive effect on the reproductive success of both men and women, although the effect of wealth is greater for men, as predicted
from evolutionary theory. The greater the number of elder brothers a man has, the lower his reproductive success, as a result
of a smaller initial herd and a later age at marriage. This is not true for women –number of elder sisters does not have a
measurable effect on a woman’s fertility, although it does have a small, negative effect on the size of her dowry. These results
are interpreted as competition between same-sex siblings for parental investment, in the form of their father’s herd, which
is more intense between sons than daughters as parental investments are greatest in males.
Received: 30 June 1995/Accepted after revision: 23 October 1995 相似文献
10.
James A. R. Marshall John M. McNamara Alasdair I. Houston 《Behavioral ecology and sociobiology》2011,65(3):417-420
The year 2009 marked both the bicentenary of Charles Darwin’s birth, and the passage of 150 years since the publication of
his revolutionary book, commonly referred to as The Origin of Species (Darwin 1859). As part of the national celebrations that took place in the UK, a meeting on ‘Mathematical Models in Ecology and Evolution’
was held in Bristol on September 10 and 11, with a special focus on the mathematical modelling and application of Darwin’s
key theories. This special issue collects together selected papers presented at the meeting, including contributions by the
four invited keynote speakers, Rob Boyd, A. W. F. Edwards, Hanna Kokko and Franjo Weissing, as well as papers received after
the event. The topics of these papers span the modelling of a very wide range of Darwin’s ideas, particularly evolution through
natural selection, the origin of species, sexual selection, altruism and cooperation, and pangenesis, as well as applications
of Darwinian thinking to the behaviour of animals, humans, and even human societies. It is hoped that this collection of papers
will provide a useful snapshot of the state-of-the-art in Darwinian theory after the last one and a half centuries, and help
to identify potential directions for research over the next. 相似文献
11.
Caroline Regina Schöner Michael Gerhard Schöner Gerald Kerth 《Behavioral ecology and sociobiology》2010,64(12):2053-2063
Many bat species regularly need to find new day roosts as they require numerous shelters each breeding season. It has been
shown that bats exchange information about roosts among colony members, and use echolocation and social calls of conspecifics
in order to find roosts. However, it is unclear if wild bats discriminate between social calls of conspecifics and other bat
species while searching for roosts. Furthermore, the extent that bats are attracted to potential roosts by each of these two
call types is unknown. We present a field experiment showing that social calls of conspecifics and other bat species both
attract bats to roosts. During two summers, we played back social calls of Bechstein’s bats (Myotis bechsteinii) and Natterer’s bats (Myotis nattereri) from different bat boxes that can serve as roosts for these species. All experimental bat boxes were monitored with infrared
video to identify the approaching bat species. Three species (M. bechsteinii, M. nattereri, and Plecotus auritus) approached the boxes significantly more often during nights when bat calls were played compared to nights without playbacks.
Bechstein’s bats and Natterer’s bats were both more attracted to social calls of conspecifics than of the other species, whereas
P. auritus did not discriminate between calls of either Myotis species. Only Bechstein’s bats entered experimental boxes and only at times when calls from conspecifics were played. Our
findings show that wild bats discriminate between social calls of conspecifics and other bat species although they respond
to both call types when searching for new roosts. 相似文献
12.
The concentration of trace elements within cephalopod statoliths can provide a record of the environmental characteristics at the time of calcification. To reconstruct accurately the environmental characteristics at the time of calcification, it is important to understand the influence of as many factors as possible. To test the hypothesis that the elemental composition of cuttlefish statoliths could be influenced by diet, juvenile Sepia officinalis were fed either shrimp Crangon sp. or fish Clupea harengus under equal temperature and salinity regimes in laboratory experiments. Element concentrations in different regions of the statoliths (core–lateral dome–rostrum) were determined using laser ablation inductively coupled plasma mass spectrometry (LA- ICPMS). The ratios of Sr/Ca, Ba/Ca, Mn/Ca and Y/Ca in the statolith’s lateral dome of shrimp-fed cuttlefish were significantly higher than in the statolith’s lateral dome of fish-fed cuttlefish. Moreover, significant differences between statolith regions were found for all analysed elements. The fact that diet adds a considerable variation especially to Sr/Ca and Ba/Ca must be taken into account in future micro-chemical statolith studies targeting cephalopod’s life history. 相似文献
13.
Many fishes are characterized by intense sperm competition between males that use alternative mating tactics. In externally
fertilizing fishes, males’ proximity to females during spawning can be an important determinant of fertilization success.
Here, we assess how mating tactic, body length, speed during streak spawns, and periphery cover affect males’ proximity to
females during sperm competition in the externally fertilizing bluegill (Lepomis macrochirus). Bluegill are characterized by three mating tactics referred to as parental, sneaker, and satellite. Parentals are territorial
and construct nests, while sneakers use a streaking behavior, and satellites use female mimicry to steal fertilizations from
parentals. We show that a small body length is important for sneakers but not for satellites to obtain a close position to
the female during spawning. Specifically, smaller sneakers obtain a closer position to females than larger sneakers in part
by positioning themselves closer on the periphery of a parental’s nest before streaking but show no difference in the speed
at which they streak. The amount of peripheral vegetation around a parental’s nest did not appear to affect proximity of sneakers
to females, and there was no relationship between the amount of peripheral vegetation and the frequency of intrusions by either
sneakers or satellites. Finally, parentals were farther from the female when a sneaker or satellite intruded than when they
spawned alone with the female. 相似文献
14.
Sperm competition is predicted to generate opposing selection pressures on males. On one hand, selection should favour ‘defensive’ adaptations that protect a male’s ejaculate from displacement, while, on the other hand, selection should favour ‘offensive’ adaptations that overcome paternity assurance mechanisms of rivals. Here, we use the sterile male technique to assess sperm precedence when a male dung beetle Onthophagus taurus mates in both a defensive (first male) and an offensive (second male) role. Significant variation in a male’s sperm precedence (both P
1 and P
2) was detected, and an individual’s defensive (P
1) and offensive (P
2) abilities were positively correlated. Thus, it appears that sexual selection simultaneously selects for ‘defensive’ and ‘offensive’ adaptations in O. taurus. We discuss a variety of male traits in O. taurus that potentially contribute to a male’s ability to be successful when mating in an ‘offensive’ and a ‘defensive’ role. 相似文献
15.
Zeshen Tian Bo Wang Yuyang Li Bo Shen Fengjuan Li Xianghua Wen 《Frontiers of Environmental Science & Engineering》2021,15(5):81
16.
Mari B. Abrahamsen Howard I. Browman David M. Fields Anne Berit Skiftesvik 《Marine Biology》2010,157(6):1251-1258
In the north Atlantic, Meganyctiphanes norvegica feeds predominantly on copepods, including Calanus spp. To quantify its perceptual field for prey, and the sensory systems underlying prey detection, the responses of tethered
krill to free-swimming Calanus spp. were observed in 3D using silhouette video imaging. An attack–which occurred despite the krill’s being tethered—was
characterized by a pronounced movement of the krill’s antennae towards the target, followed by a propulsion and opening of
the feeding basket. Frequency distributions of prey detection distances were significantly different in the light vs. the
dark, with median values of 26.5 mm and 19.5 mm, respectively. There were no significant differences in the angles at which
prey were detected by krill (relative to the predator’s longitudinal body axis) in the light vs. the dark. Prey detections
were symmetrically distributed on either side of the predator, in both light and dark. However, significant asymmetry was
found in the dorsal–ventral direction with 80% of the prey detections located below the midline of the krill’s body axis and,
given the placement and orientation of the compound eyes, presumably outside its visual field of view. This indicates that,
at least under these conditions, vision was not the main sensory modality involved in the detection of active prey by M. norvegica. However, under some circumstances, vision may provide supplemental information. Avoidance responses of copepod prey were
nearly twice the velocity of their nominal background swimming speed (153 ± 48 and 85 ± 75 mm s−1, respectively), on average taking them 43 ± 16 mm away from the predator. This is far beyond the krill’s perceptual range,
suggesting that the escape reaction provides an effective deterrent to predation (although perhaps less so for free-swimming
krill). This information can be used to parameterize models that assess the role of krill as predators in marine ecosystems. 相似文献
17.
Hong Yang Xianjin Huang Jianlin Hu Julian R. Thompson Roger J. Flower 《Frontiers of Environmental Science & Engineering》2022,16(8):111
China has been committed to achieving carbon neutrality by 2060. China’s pledge of carbon neutrality will play an essential role in galvanising global climate action, which has been largely deferred by the Covid-19 pandemic. China’s carbon neutrality could reduce global warming by approximately 0.2–0.3 °C and save around 1.8 million people from premature death due to air pollution. Along with domestic benefits, China’s pledge of carbon neutrality is a “game-changer” for global climate action and can inspire other large carbon emitters to contribute actively to mitigate carbon emissions, particularly countries along the Belt and Road Initiative (BRI) routes. In order to achieve carbon neutrality by 2060, it is necessary to decarbonise all sectors in China, including energy, industry, transportation, construction, and agriculture. However, this transition will be very challenging, because major technological breakthroughs and large-scale investments are required. Strong policies and implementation plans are essential, including sustainable demand, decarbonizing electricity, electrification, fuel switching, and negative emissions. In particular, if China can peak carbon emissions earlier, it can lower the costs of the carbon neutral transition and make it easier to do so over a longer time horizon. China’s pledge of carbon neutrality by 2060 and recent pledges at the 26th UN Climate Change Conference of the Parties (COP26) are significant contributions and critical steps for global climate action. However, countries worldwide need to achieve carbon neutrality to keep the global temperature from growing beyond the level that will cause catastrophic damages globally. 相似文献
18.
The local resource enhancement (LRE) model predicts that in cooperatively breeding species, sex ratios will be biased in favor
of the more helpful sex. In this study, we assess the assumptions underlying the LRE model in a population of cooperatively
breeding wild dogs (Lycaon pictus) in Northern Botswana monitored over a 15-year period. In this population, litter size and pup survival to 1 year are strongly
affected by pack size and the breeding female’s age, but adult males have a stronger and more linear effect on females’ reproductive
performance than do adult females. This asymmetry in the benefits derived from male and female helpers is reflected in male-biased
sex ratios in litters at the time pups emerge from the den. Sex ratio biases are most pronounced in the litters of the youngest
mothers who live in significantly smaller packs than older females. The presence of potential rivals for the dominant female’s
position depresses pup production at the time of emergence, suggesting that competition among females for breeding positions
may also contribute to the selective forces affecting birth sex ratios. 相似文献
19.
Summary. The formicine ant Paratrechina longicornis is known for its extremely opportunistic foraging behaviour. Only a single trail pheromone source, the rectum, was previously
described from this ant. Our detailed examination of this ant’s chemical communication system revealed the presence of at
least four sources of pheromones. Rectum, poison sac, and Dufour gland contain orientation components with decreasing effectiveness
and persistence (in the sequence mentioned) as well as attractants with increasing effectiveness. Furthermore, the mandibular
gland contains repellents, and a releaser of defensive behaviour. This set of various signals of different strength and persistence
allows an extraordinary degree of flexibility and efficiency in the collective behaviour of P. longicornis, especially food exploitation, and thus may contribute to this insect’s overall ecological success. 相似文献
20.
Elvan Ceyhan 《Environmental and Ecological Statistics》2010,17(3):247-282
For two or more classes (or types) of points, nearest neighbor contingency tables (NNCTs) are constructed using nearest neighbor
(NN) frequencies and are used in testing spatial segregation of the classes. Pielou’s test of independence, Dixon’s cell-specific,
class-specific, and overall tests are the tests based on NNCTs (i.e., they are NNCT-tests). These tests are designed and intended
for use under the null pattern of random labeling (RL) of completely mapped data. However, it has been shown that Pielou’s
test is not appropriate for testing segregation against the RL pattern while Dixon’s tests are. In this article, we compare
Pielou’s and Dixon’s NNCT-tests; introduce the one-sided versions of Pielou’s test; extend the use of NNCT-tests for testing
complete spatial randomness (CSR) of points from two or more classes (which is called CSR independence, henceforth). We assess the finite sample performance of the tests by an extensive Monte Carlo simulation study and demonstrate
that Dixon’s tests are also appropriate for testing CSR independence; but Pielou’s test and the corresponding one-sided versions
are liberal for testing CSR independence or RL. Furthermore, we show that Pielou’s tests are only appropriate when the NNCT
is based on a random sample of (base, NN) pairs. We also prove the consistency of the tests under their appropriate null hypotheses.
Moreover, we investigate the edge (or boundary) effects on the NNCT-tests and compare the buffer zone and toroidal edge correction
methods for these tests. We illustrate the tests on a real life and an artificial data set. 相似文献