共查询到20条相似文献,搜索用时 46 毫秒
1.
J.-L. Mercier J.-C. Lenoir A. Eberhardt S. Frohschammer C. Williams J. Heinze 《Insectes Sociaux》2007,54(4):403-411
Sex appears to be a rather prosaic and casual event in the life of most social Hymenoptera. In contrast, mating in the ant
genus Cardiocondyla is regularly preceded by a prolonged and stereotypic courtship display. Pummeling the head of the female with mandibles and
/ or antennae and vibrations of the gaster, presumably stridulation, are essential parts of male courtship. The overall structure
of the mating pattern is conserved throughout species and between winged and wingless, “ergatoid” males, but exhibits species-specific
idiosyncrasies. For example, C. elegans males regularly end the interaction with a female with a short mouth-to-mouth contact. Variation in the duration of the precopulatory
phase and the copulation itself might reflect different degrees of inter- and intrasexual selection. More information on the
dynamics of sperm transfer and the risk and intensity of sperm competition are needed to better understand the evolution of
the complex mating behavior in this genus.
Received 15 December 2006; revised 25 June 2007; accepted 11 September 2007. 相似文献
2.
We studied the predatory behavior of seven species of the genusLeptogenys from Mexico and Cameroon. The ants of this genus are armed with long, thin, curved mandibles articulated at the extreme corners
of the anterior margin of the head, permitting them easily to seize oniscoid isopods, the obligate or the principal prey of
mostLeptogenys species. Workers hunt these prey, which are able to roll themselves up, solitarily. Foraging behavior comprises sequences
of up to eight activities. The prey can be seized by the body (rolled up or not), or alternatively by the edge of the shell,
then turned over and stung on the ventral face. A relationship between the mandible size of the workers and the handling method
permitted us to established that the phase “seizure by the edge of the shell” (compared to grasping the prey by the body)
was more frequent as the prey size increased or the mandible length of the workers decreased. The rate of prey escape followed
the same pattern. When a prey escaped, workers reacted by using a local searching or “reserve” behavior: they moved by increasing
both sinuosity and speed. Recruitment occurred mainly after a worker found a group of prey or a large prey.L. mexicana are attractive at a distance to the isopods Bathytropidae living in the same natural environment. As a consequence, prey
capture is possible without foraging for this species. 相似文献
3.
Laboratory observations were conducted on four separate red imported fire ant, Solenopsis invicta, colonies that contained workers parasitized by the decapitating fly, Pseudacteon tricuspis. Parasitized S. invicta workers remained inside the nest during parasitoid larval development and left the nest approximately 8 – 10 hours before
decapitation by the parasitoid. When parasitized ants left the nest, they were highly mobile, were responsive to tactile stimuli,
and showed minimal defensive behavior. Ants ultimately entered into a grass thatch layer, where they were decapitated and
the fly maggots pupariated. This study reveals that parasitized ants exhibit behaviors that are consistent with host manipulation
to benefit survival of the parasitoid.
Received 9 November 2006; revised 26 January 2007; accepted 7 February. 相似文献
4.
Courtship and spawning behavior is described for the Leather Bass, Dermatolepis dermatolepis, from observations made from a manned submersible at Cocos Island, Costa Rica on 19 days between November 2006 and February
2007. Spawning occurred in the evening (16:00–18:30 h) in subgroups of 10–32 individuals that formed within aggregations of
50–70 individuals. The mating sequence was characterized by subgroup formation and crowding behavior followed by a brief vertical
spawning rush, gamete release, and the rapid separation of participants. The aggregation was present on all dives, and spawning
was not restricted to specific lunar phases. 相似文献
5.
D. E. Tyler 《Human Evolution》2001,16(3-4):151-158
There are now eleven known mandibular pieces from the Lower and Middle Pleistocene of Java, all but one being from the Sangiran
site. All of these have been assigned toHomo erectus by most authorities, while others have suggested as many as four different hominoid taxa. Two of the mandibles, Sangiran
33 (Mandible H) and“Meganthropus”D (no Sangiran number yet assigned), are described here for the first time. The two new mandibles come from the Upper Pucangan
Formation and date approximately 1.2–1.4 Myr. They are morphologically compatible with other“Meganthropus” mandibles described from Java. Despite attempts by numerous authorities to place all the Sangiran hominid mandibles in the
species,H. erectus, the range of variation in metric and nonmetric features of the“Meganthropus” hominids is clearly beyond the know variation found inH. erectus. “Meganthropus” could represent a speciation from the well-knownH. erectus. 相似文献
6.
Termites, Coptotermes formosanus, reared individually, were highly susceptible to the entomopathogenic fungus, Metarhizium anisopliae, while termites reared in␣groups were highly resistant. When reared in groups, the termites treated with M.␣anisopliae conidia on the body surface were groomed by their nestmates and more than 80% of the conidia were removed from the cuticle
within 3 h. However, there was not a significant reduction in the numbers of conidia on the body surfaces of termites reared
individually. For the termites maintained in groups, conidia were found in foreguts, midguts and hindguts, but very few conidia
were detected in the guts of termites reared individually. Conidia in the alimentary tracts did not germinate, but some of
were alive. As a result, it seems that the removal of foreign bodies, such as fungal conidia, from the␣cuticle is one function
of termite mutual grooming behavior and that conidia removed from the cuticle are eliminated through alimentary tracts. This
study indicates that mutual grooming behavior is very effective in protecting these termites from M.␣anisopliae infection. 相似文献
7.
Pteromalus cerealellae (Ashmead) (Hymenoptera: Pteromalidae) is an ectoparasitoid of several stored-product insect pests. Very little information
has been published on its biology and development in host larvae, which typically are concealed within seeds. We documented
the development of P. cerealellae within fourth instar larvae of its concealed host, Callosobruchus maculatus (F.) (Coleoptera: Chrysomelidae) infesting cowpea seeds. The preimaginal life stages of the parasitoid were characterized
for the first time using morphological structures revealed by microscopic techniques including scanning electron microscopy. Pteromalus cerealellae produces hymenopteriform eggs and larvae. Eggs hatch into 13-segmented first instar larvae with peripneustic condition of
spiracles. The larvae have simple, tusk-like mandibles, whereas the mandibles of the pupae and the adults are of the conventional
toothed types. Using statistical analyses of the sizes of the larval mandibles and head capsules in conjunction with reliable
characters such as the number of exuviae on the body of parasitoid larvae, cuticular folding, and excretion of the meconium,
we recorded four larval instars for P. cerealellae. The data showed significant positive correlations between larval mandible lengths and widths of larval head capsules, as
well as between mandible lengths and larval instars, suggesting that mandible length is a good predictor of the number of
instars in P. cerealellae. Developmental time from egg to adult emergence was ∼12 d for females and ∼11 days for males at 30 ± 1°C, 70 ± 5% r.h. and
12L:12D photoperiod. 相似文献
8.
Ant-gardens represent a special type of association between ants and epiphytes. Frequently, two ant species can share the
same nest in a phenomenon known as ‘parabiosis’, but the exact nature (i.e., mutualistic or parasitic) of this interaction
is the subject of debate. We thus attempted to clarify the mutual costs and benefits for each partner (ants and plants) in
the Crematogaster levior/Camponotus femoratus ant-garden parabiosis. The ants’ response to experimental foliar damage to the epiphytes and to the host tree as well as
their behavior and interactions during prey capture were investigated to see if the purported parasitic status of Cr. levior could be demonstrated in either the ant-ant or in the ant-plant interactions. The results show that both species take part
in protecting the epiphytes, refuting the role of Cr. levior as a parasite of the ant-garden mutualism. During capture of large prey Ca. femoratus took advantage from the ability of Cr. levior to discover prey; by following Cr. levior trails Ca. femoratus workers discover the prey in turn and usurp them during agonistic interactions. Nevertheless, the trade-off between the costs
and benefits of this association seems then to be favorable to both species because it is known that Cr. levior benefits from Ca. femoratus building the common carton nests and furnishing protection from vertebrates. Consequently, parabiosis can then be defined
as the only mutualistic association existing between ant species, at least in ant-gardens.
Received 31 August 2006 ; revised 8 December 2006 ; accepted 12 December 2006 相似文献
9.
In Oecophylla, an ant genus comprising two territorially dominant arboreal species, workers are known to (1) use anal spots to mark their territories, (2) drag their gaster along the substrate to deposit short-range recruitment trails, and (3) drag the extruded rectal gland along the substrate to deposit the trails used in long-range recruitment. Here we study an overlooked but important marking behavior in which O. longinoda workers first rub the underside of their mandibles onto the substrate, and then—in a surprising posture—tilt their head and also rub the upper side of their mandibles. We demonstrate that this behavior is used to recruit nestmates. Its frequency varies with the rate at which a new territory, a sugary food source, a prey item, or an alien ant are discovered. Microscopy analyses showed that both the upper side and the underside of the mandibles possess pores linked to secretory glands. So, by rubbing their mandibles onto the substrate, the workers probably spread a secretion from these glands that is involved in nestmate recruitment. 相似文献
10.
Colony social organization in the fire ant Solenopsis invicta appears to be under strong genetic control. In the invasive USA range, polygyny (multiple queens per colony) is marked by
the presence of the Gp-9
b
allele in most of a colony’s workers, whereas monogyny (single queen per colony) is associated with the exclusive occurrence
of the Gp-9
B
allele. Ross and Keller, Behav Ecol Sociobiol 51:287–295 (2002) experimentally manipulated social organization by cross-fostering queens into colonies of the alternate form, thereby changing
adult worker Gp-9 genotype frequencies over time. Although these authors showed that social behavior switched predictably when the frequency
of b-bearing adult workers crossed a threshold of 5–10%, the possibility that queen effects caused the conversions could not be
excluded entirely. We addressed this problem by fostering polygyne brood into queenright monogyne colonies. All such treatment
colonies switched social organization to become polygyne, coincident with their proportions of b-bearing workers exceeding 12%. Our results support the conclusion that polygyny in S. invicta is induced by a minimum frequency of colony workers carrying the b allele, and further confirm that its expression is independent of queen genotype or history, worker genotypes at genes not
linked to Gp-9, and colony genetic diversity. 相似文献
11.
Summary Interspecific facultative social parasitism is well known in ants and in bumble-bees, but it is rarer in wasps. This form of parasitism is traditionally considered to be an intermediate stage in the evolution of obligate interspecific parasitism, where the parasites are no longer able to nest alone. We report field and experimental observations of a newly discovered facultative parasitic relationship between two closely related free-living Polistes species: P. nimphus and P. dominulus. P. nimphus foundresses sometimes usurp the nests of the larger P. dominulus before worker emergence. The invading queen takes over the nest with abundant abdomen stroking on the nest surface and is accepted by workers if they emerge 6 or more days after usurpation. Morphometric comparisons show that the usurper species, though smaller than its victims, has morphological adaptations consisting of larger heads, mandibles and front femora relative to their body size that may give it an advantage during nest invasion. This strategy is likely to be taken only after the foundress loses her original nest because invading P. nimphus queens have lower reproductive success than they would have had on their own nest. Overall, we found that P. nimphus usurpers use strategies of invasion similar to those of two obligate parasites, suggesting that this may be an example of one of the pathways by which social parasitism evolved.Received 4 April 2003; revised 8 August 2003; accepted 14 September 2003. 相似文献
12.
The success of all insect societies relies on their ability to maintain optimal levels of different castes. Here we report
on an apparent free-running circannual rhythm that optimizes the developmental time of the soldier caste of Coptotermes formosanus Shiraki. Over a 3 year period, bioassays were conducted each month (except June) with groups of 100 termite workers in a
28°C incubator in total darkness. The number of days needed for C. formosanus soldiers to develop varied depending on the time of the year (month). In March, just prior to the major swarming exodus for
alates (April to June), 9 days were required before a worker molted to a presoldier. Longer times were required for such a
molt in all other months, with an increasing trend from April to December (from 13 to 30 days) and a decreasing trend from
January to February (from 25 to 12 days). Colony origin or the length of time that termites were kept in the laboratory under
constant conditions (26 – 28°C, 70 – 80% RH) before testing (7 days – 1 year) did not affect this rhythm. This is the first
demonstrated evidence of a free-running circannual rhythm in a social insect.
Received 23 July 2007; revised 9 and 21 August 2007; accepted 23 August 2007. 相似文献
13.
S. C. Pratt 《Insectes Sociaux》2005,52(4):383-392
This paper examines the individual behavior underlying collective choice among nest sites by the ant Temnothorax (formerly Leptothorax) curvispinosus. Colonies can actively compare options, rejecting a mediocre site when it is paired with a good one, but accepting the same
mediocre design if it is instead paired with a worse site. This ability emerges from the behavior of an active minority of
workers who organize emigrations. When one of these finds a promising site, she recruits nest mates to it, but only after
a delay that varies inversely with site quality. Ants first recruit fellow active ants via slow tandem runs, but eventually
switch to speedier transports of the colony’s passive majority. Later transports grow faster still, as ants improve their
speed with experience. An ant’s choice of recruitment type is governed by a quorum rule, such that her likelihood of starting
to transport increases with the population of the new site. The size of the quorum depends on experience, with ants demanding
a larger population to launch immediately into transport than they do to switch to transport after first leading a few tandem
runs. Perception of quorum attainment requires direct contact between ants. The ants’ behavior qualitatively matches that
of T. albipennis, where models have shown that decentralized choice of the best site depends on quality-dependent recruitment delays, amplified
by a quorum rule for initiating transport. Parameter estimates for an agent-based model show significant quantitative differences
between the species, and suggest that T. albipennis may place relatively greater emphasis on emigration speed.
Received 11 February 2005; revised 10 May 2005; accepted 20 May 2005. 相似文献
14.
Apterostigma collare Emery is a highly derived fungus-growing ant within the Tribe Attini whose small, fungal nests are found in tropical rain
forests. This study focuses on determining the colony structure of A. collare, specifically searching for evidence of polydomy or independence. We surveyed and observed nests in the field, and performed
foraging bioassays and dissected nests in the laboratory. We determined the size and contents of nests in field populations.
Nests found near other nests were not statistically different in size compared to nests found alone. There was also no statistical
difference between near and lone nests regarding the presence of a queen in the nest. Most nests contained one queen with
brood and workers, regardless of their proximity to other nests. Observations also were made of foraging and trail-marking
behaviors. Foraging activity observed in the field revealed that workers left the nest area and followed trails upwards into
the canopy, but they did not interact with foragers from other nearby nests. In a laboratory foraging arena, foragers marked
a trail to a food source by dragging the gaster. Bioassays showed that A. collare workers preferred their own foraging trails, but not those of other conspecific colonies. All results suggest that each nest
represents an independent colony, supporting a previous report that nests found in close proximity do not constitute a polydomous
colony.
Received 19 July 2006; revised 23 March 2007; accepted 6 June 2007. 相似文献
15.
Ant colonies that undergo long starvation periods have to tune their exploratory and foraging responses to face their food
needs. Although the number of foragers is known to increase with food deprivation in the ant Lasius niger, such enhanced food exploitation is not related to a more intense recruitment by successful scouts. We thus suggest that
the colony’s response to a food shortage could result from changes at the level of the ant recruits, in particular from changes
in their spatial organization inside the nest. Since aggregation plays a key role in the social organization of ants, we assume
that the colony’s response to starvation could be due to changes in the aggregative behaviour of L. niger nestmates.We thus compared the aggregation dynamics of inner-nest workers and foragers having undergone either a short or
a long-lasting starvation period. Whatever the ethological group (foragers or inner-nest workers), there was no significant
influence of starvation on the aggregation dynamics nor on any feature of the observed clusters. This result shows that an
increased foraging response to food shortage cannot be explained by changes in the tendency of nestmates to aggregate within
the nest. Finally, we discuss other behavioural mechanisms, in particular changes in behavioural thresholds that could underlie
the adaptive changes seen in colony foraging after long starvation periods.
Received 25 June 2007; revised 21 January 2008; accepted 24 January 2008. 相似文献
16.
Den sharing by conspecific spiny lobsters (aggregation) is modulated by chemical attraction but may confer several, not necessarily
mutually exclusive, antipredator byproduct benefits: a “guide effect”, which only benefits the individual attracted to a sheltered
conspecific; a “dilution effect”, which reduces per-capita risk of predation simply through aggregation; or active “group
defense”. Each potential benefit has a different set of predictors (relationships between aggregation and conspecific or predator
densities), but conflicting results could suggest the simultaneous operation of more than one benefit. These predictions were
tested for coexisting Panulirus guttatus (a reef-obligate) and Panulirus argus (a temporary reef-dweller) using data collected during 11 surveys on fixed sites over a coral reef in Mexico. P. guttatus greatly outnumbered P. argus, but P. argus showed a greater tendency to aggregate. All three benefits of den sharing operated for the more social P. argus, with “group defense” being of the most benefit for larger individuals, and the “guide” and “dilution” effects for smaller
individuals recently immigrating into the reef habitat and sharing dens with larger conspecifics. P. guttatus did not display “group defense” and its aggregations appeared to be modulated by the interplay between attraction and aggressive
behaviors. This species relied more on solitary crypticity, especially at larger sizes, but appeared to benefit from a “guide
effect” at high conspecific densities. In experimental tanks, each species tended to aggregate when tested separately, but
when tested jointly, aggregation among P. guttatus was significantly reduced. The experimental results reflect the differential patterns of aggregation between the fore-reef,
where P. guttatus dominated, and the back-reef, where coexistence of both species was greater. 相似文献
17.
The Southeast Asian nasute termite Longipeditermes longipes forages on the open ground on leaf litter. Its monomorphic workers carry back food balls in their mandibles while dimorphic soldiers defensively surround the marching columns and the foraging patches. When mechanically disturbed, workers hide under the litter, whereas antennating soldiers face as closely as possible the source of disturbance. Foragers prefer the lower, nitrogen-rich layer of the litter. Soldier behavior and column organization (returning workers in the center lanes, outgoing workers in the two flanking lanes) are similar to those in the related genera Hospitalitermes and Lacessititermes, which, however, tend to forage above ground. 相似文献
18.
Effect of Average Worker Size on Tunneling Behavior of Formosan Subterranean Termite Colonies 总被引:2,自引:1,他引:1
The effect of a colony's average worker size on tunneling behavior of Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) in laboratory foraging arenas was investigated. Large groups of foragers from four colonies were added to arenas and allowed to tunnel for a period of 22 days. Various aspects of the resulting tunnel galleries were analyzed using ANOVA and regression analysis. After the exclusion of one colony due to high mortality, the only parameters shown to differ significantly were tunnel width and tunnel segmentation. Larger workers tended to construct less segmented galleries with wider tunnels. Tunnel length was positively correlated to size on the first 2 days, but the relationship reversed by day 4. Tunneling on day 1 was positively correlated to the discovery of food items. Our results indicate that a foraging group's average worker size can affect tunnel pattern and that groups composed of larger workers are better tunnelers, but groups of smaller sized workers are able to make up the difference over time. Possible explanations for size-related variation in tunneling behavior are discussed. 相似文献
19.
We observed a case of infant adoption in an unprovisioned group of wild black-fronted titi monkeys (Callicebus nigrifrons). During our long-term field study we noticed that an infant had moved from one of our study groups (“Desbotado”) to another
(“Rio”). Observations of the adoptive group confirm that it was being cared for by the adult male, and initially the group’s
adult female was nursing the infant alongside her biological infant. Interestingly, the native and adoptive groups have frequent
inter-group interactions, but at no point have we observed the native group trying to retrieve its infant. As of April 2007
the infant has been living in its adoptive group for 19 months. These data document the first case of adoption in this genus;
they suggest that infant recognition is poorly developed in this species and that under certain circumstances wild groups
of C.
nigrifrons can successfully rear twins. In our study population reproductive females give birth to one infant every year; the only case
when this has not happened is with the group that adopted the infant, suggesting that adoption may generate a reproductive
cost. 相似文献
20.
Worker honey bees from genetic strains selected for being resistant (R) or susceptible (S) to tracheal mites typically show
large differences in infestation in field colonies and in bioassays that involve controlled exposure to infested bees. We
used bioassays exposing newly emerged individuals to infested workers to compare the propensity for tracheal mites to infest
queens, drones and workers from R and S colonies. In tests with queens, newly emerged R and S queens were either simultaneously
confined in infested colonies (n = 95 and 87 respectively), or individually caged with groups of 5–20 infested workers (n = 119 and 115 respectively). Mite prevalence (percentage of individuals infested) and abundance (foundress mites per individual)
after 4–6 days did not differ between R and S queens. In another test, five newly emerged drones and workers from both an
R and an S colony, and a queen of one of the two strains, were caged in each of 38 cages with 20 g of workers infested at
60–96% prevalence. Infestations of the R queens (n = 17) and S queens (n = 19) did not differ significantly, but R workers had half the mite abundance of S workers, while R drones received about
a third more migrating mites than S drones. In tests to evaluate possible mechanisms, removal of one mesothoracic leg from
R and S workers resulted in 2- to 10-fold increase in mite abundance on the treated side, but excising legs did not affect
infestation of the corresponding tracheae in drones. This suggests that differences in infestation between R and S workers,
but not drones, are largely determined by their ability to remove mites through autogrooming. If autogrooming is the primary
mechanism of colony resistance to tracheal mites, selection for resistance to tracheal mites using infestation of hemizygous
drones may be inefficient.
*The U.S. Government’s right ot retain a non-exclusive, royalty-free licence in and to any copyright is acknowledged. 相似文献