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231.
We examined factors that determine the outcome of agonistic encounters between male pygmy swordtail fish. Xiphophorus nigrensis and X. multilineatus males formed dominance relationships based on body size in staged laboratory encounters. There was a significant negative correlation between size asymmetry and fight intensity, suggesting that males assessed size in the encounters. However, a significant proportion of the variation in fight intensity in contests that escalated to bites could not be explained by size asymmetry. Aggressive motivation may also influence the outcome of contests and could be assessed in agonistic encounters. Theory suggests that signals of aggressive intention will be evolutionarily stable if individuals can recognize opponents and encounter one another repeatedly. In addition, individual recognition is one way that dominance hierarchies can be maintained. Here we demonstrate that males from both species can recognize individuals. In addition, at least some X. nigrensis males were site-faithful in the field, suggesting males encounter the same opponents repeatedly.Communicated by G.M. Klump 相似文献
232.
Some territorial animals exhibit a form of social recognition, commonly termed the "dear enemy effect", in which territory residents display lower levels of aggression toward familiar neighbors compared to unfamiliar individuals who are non-territorial "floaters". Despite the widespread occurrence of territorial social systems and use of acoustic signals for communication in anuran amphibians, only two previous studies have demonstrated vocally mediated dear enemy behavior in a territorial frog. In this study, I conducted neighbor-stranger discrimination playback experiments in a third species of territorial frog, the strawberry dart-poison frog, Dendrobates pumilio (Anura, Dendrobatidae). In the first experiment (n=24), I broadcast the calls of a subject's nearest neighbor and the calls of an unfamiliar individual from the approximate midpoint between the subject's and the neighbor's territories. Although males responded to the stimuli, they did not exhibit differential responses to the calls of neighbors and strangers. In a second experiment (n=22), I broadcast the calls of a neighbor and a stranger to subjects through a speaker located in the approximate center of the neighbor's territory. Males also responded to the playback, although less intensely than in the first experiment, but no discrimination between the calls of neighbors and strangers was found. Thus, territorial males of the strawberry dart-poison frog appear not to discriminate behaviorally between the advertisement calls of neighbors and strangers. Several proximate and ultimate-level hypotheses for this lack of vocally mediated neighbor-stranger discrimination are discussed.Communicated by T. Czeschlik 相似文献
233.
Nestmate recognition for eggs in the honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.)
Christian W. W. Pirk Peter Neumann Randall Hepburn 《Behavioral ecology and sociobiology》2007,61(11):1685-1693
Colony integrity is fundamental to social insects and is threatened by the reproduction of non-nestmates. Therefore, discrimination
between eggs derived from nestmates and non-nestmates would constitute an adaptation to prevent exploitation of the entire
cooperative group by unrelated individuals. The removal of nestmate and non-nestmate queen and worker-laid eggs was evaluated
in honeybees using colonies of Apis mellifera capensis to test female and of A. m. scutellata to test male eggs. The data show that honeybees can distinguish between nestmate and non-nestmate eggs of both sexes. Moreover,
non-nestmate female queen-laid eggs were removed significantly faster than nestmate female worker-laid eggs in A. m. capensis, indicating that nestmate recognition cues can override caste-specific ones. While the experimental manipulation accounts
for 37.2% (A. m. scutellata) or 1.6% (A. m. capensis) of variance in relation to egg removal, nestmate recognition explains 33.3% for male eggs (A. m. scutellata) and 60.6% for female eggs (A. m. capensis), which is almost twice as high as the impact of caste (16.7% A. m. scutellata; 25% A. m. capensis). Our data show a stronger effect of nestmate recognition on egg removal in the honeybee, suggesting that cues other than
caste-specific ones (viability/kin) can dominate egg removal behavior. In light of intraspecific social parasitism, preventing
the reproduction of unrelated individuals (group selection) rather than preferring queens’ eggs (kin selection) appears to
be the driving force behind the evolution of egg removal behavior in honeybees. 相似文献
234.
Iguanian lizards perform conspicuous species-typical push-up displays, which are used in territory advertisement, threat, and courtship contexts. Subtle individually distinctive differences in push-up characteristics have been suggested to play a role in the recognition of social partners. However, if the structure of push-ups is responsive to changing physiological states then their capacity to promote recognition may be limited. The current study evaluated whether the push-ups performed while in an experimentally imposed state of fatigue by male side-blotched lizards (Uta stansburiana), retain the individually distinctive characteristics apparent in rested lizards. We found repeatable among-individual differences in the duration and the relative height of push-up components. Repeatability values did not change consistently between the rested and fatigued conditions, nor when both conditions were pooled, indicating that these push-up characteristics do not change with fatigue. Similarly, discriminant functions that were generated using push-ups from one state assigned push-ups performed in an alternate state to the correct individuals. Furthermore, when analyzed independently of individual identity, the values of display parameters examined in the current study did not change significantly between states, and discriminant function analysis could not reliably classify push-ups to the correct state. Taken together the results show that individually distinctive push-up characteristics are robust to effects of fatigue, consistent with their suggested role in social recognition. In the future, video playback experiments can test whether lizards utilize the signature-like characteristics of push-ups to discriminate among individuals.Communicated by T. Czeschlik 相似文献
235.
The ability of territorial males to discriminate between songs of their neighbors and songs of strangers has been demonstrated in 27 species of songbirds. Such experiments test only the ability of a subject to discriminate between two classes of stimuli, familiar (neighbors) and unfamiliar (strangers) songs. Individual recognition of neighbors is a finer, more complex type of discrimination. The ability of territorial males to recognize individual neighbors by song has been documented in 12 species of oscine passerines (Passeriformes, Passeri), but has never been demonstrated in suboscine passerines (Tyranni). We investigated recognition of songs of individual neighbors in a suboscine, the alder flycatcher (Empidonax alnorum). We performed a series of song playback experiments and recorded responses of territorial males to songs of neighbors and songs of strangers broadcast from two locations, the neighbor boundary and an opposite boundary. Subjects responded more aggressively to songs of a neighbor when played from the opposite boundary than when played from the neighbor boundary. They responded with equal aggression to songs of strangers regardless of location of playback. The difference in response to neighbor songs between speaker locations and the lack of a difference in response to stranger songs indicate that territorial males associate a particular song with a particular location (territory), and thus recognize individual neighbors.Communicated by I. Hartley 相似文献
236.
Summary. Molecular studies suggest that the Iberian wall lizard, Podarcis hispanica, forms a species complex with several monophyletic types. In Central Spain two of these types are spatially not isolated
and may interact. Sex pheromones are important for species recognition and, thus, differences between lizards’ types in chemicals
used in intraspecific communication could lead to reproductive isolation. Analyses by GC-MS showed that the femoral gland
secretions of adult males of different types were different. Males of one type had twelve exclusive compounds, and proportions
of some shared compounds differed. This presumably would reflect selection for the persistency and efficiency of chemical
signals in different environments; less volatile compounds and with a higher chemical stability being favoured in the type
of lizards inhabiting more humid climatic conditions. Differential tongue-flick rates to scents from femoral secretions indicated
that males were able to detect and discriminate between males of different types based on chemical cues alone. In contrast,
females detected but did not seem able to discriminate between scents of the two types of males. Thus, multiple factors might
be simultaneously acting either against or in favor of speciation, leading, on the one hand, to genetic differences between
types, but, on the other hand, probably precluding an effective reproductive isolation in areas where both types of lizards
may interact. 相似文献
237.
This paper demonstrates that while pattern formation can stabilize individual-based models of predator–prey systems, the same individual-based models also allow for stabilization by alternate mechanisms, particularly localized consumption or diffusion limitation. The movement rules of the simulation are the critical feature which determines which of these mechanisms stabilizes any particular predator–prey individual-based model. In particular, systems from well-connected subpopulations, in each of which a predator can attack any prey, generally exhibit stabilization by pattern formation. In contrast, when restricted movement within a (sub-)population limits the ability of predators to consume prey, localized consumption or diffusion limitation can stabilize the system. Thus while the conclusions from differential equations on the role of pattern formation for stability may apply to discrete and noisy systems, it will take a detailed understanding of movement and scales of interaction to examine the role of pattern formation in real systems. Additionally, it will be important to link an understanding of both foraging and inter-patch movement, since by analogy to the models, both would be critical for understanding how real systems are stabilized by being discrete and spatial. 相似文献
238.
Freddie-Jeanne?RichardEmail author Abraham?Hefetz Jean-Philippe?Christides Christine?Errard 《Chemoecology》2004,14(1):9-16
Summary. Neotropical Fungus-growing leaf-cutting ants (tribe Attini) live in
obligatory symbiosis with a fungus, which they grow on fresh leaves harvested by
workers. Colonial recognition is likely based on chemical cues provided by cuticular
hydrocarbons that have been found to be partly influenced by environmental odor
sources. The diet breadth of Acromyrmex
subterraneus subterraneus enabled us to test
the impact of different plant diets on colonial recognition. The intermediary of the
fungus in the ants feeding habit adds a special angle to the question.
From a queenright (QR) mother colony of A. s. subterraneus
we formed several groups of queenless (QL) workers with fungus (approx. 700 ants). The QR
colony and two of the QL-groups were fed with the same diet of fresh bramble leaves. Two other
QL-groups were fed with privet leaves and two with rose flowers. After 4 months, QR workers were
significantly more aggressive towards the QL-group fed with rose flowers or privet
leaves than towards workers of the QL-groups fed with fresh bramble leaves. Rose-fed
QL workers were aggressive towards privet-fed QL workers and vice versa, but never towards
workers of their counterpart group that fed on the same diet. These results suggest
that the absence of the queen or the separation time between groups played a minor
role in shaping nestmate recognition cues as compared to the diet. The behavioral
studies were supplemented by chemical analyses of cuticles, postpharyngeal glands
(PPG) and plant-food extracts revealing profiles variations that were correlated
with the dietary changes. However, although the plant extract contained several
hydrocarbons there was no congruency between the plant profile and the respective
diet-group ants. These results support the hypothesis that the diet influences
indirectly the chemical profiles and consequently the recognition cues in
A. s. subterraneus. 相似文献
239.
Leonardo?DapportoEmail author Cristina?Pansolli Stefano?Turillazzi 《Behavioral ecology and sociobiology》2004,56(4):315-321
Various studies indicate that cuticular hydrocarbons (CHCs) act as cues for nestmate recognition in paper wasps and other social insects. A recent study showed that associative nest foundation in Polistes dominulus is mainly performed by foundresses coming from the same locality. In the present study, we induced future foundresses of P. dominulus collected in two different localities to hibernate in the laboratory in aggregates of individuals from the same or different localities. After 2 months of hibernation, foundresses from different localities but from the same experimental cluster did not show any preference to associate, at the time of nest foundation, with individuals coming from the same original locality. The cuticular chemical profiles of individuals from the mixed hibernation clusters were quite similar and significantly different from those of individuals which hibernated with other foundresses from the same locality. These findings suggest that, in this species, mechanisms other than nestmate chemical recognition play a major role in the spring association of gynes during the foundation of a new nest.Communicated by R.F.A. Moritz 相似文献
240.