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1.
The social pseudoscorpion Paratemnoides nidificator is a common species in the Brazilian tropical savannah (Cerrado), where colonies are found under the bark of trees. In this environment, colonies hunt for large insects, subduing them by cooperative effort. Small insects are offered as food to nymphs, but large prey tends to be shared by colony members. We investigated the cooperative capture of large prey (Scarabaeidae beetles) by colonies of P. nidificator. During this process, some adults are involved in the immobilization and killing of prey. However, other adults stay as profiteers and do not offer help to subdue the prey. After prey immobilization, pseudoscorpions perform a hierarchical food share in which the attackers begin sucking the prey. These individuals favor the nymphs, offering them the prey and protection during feeding. Profiteer individuals are the last to feed on the carcass. In P. nidificator, obligatory parental care probably favors the evolution of behavioral strategies that prioritize the feeding of juveniles. This mechanism can provide better-quality food for the attackers but offers food to all colony members. 相似文献
2.
Masayoshi Maehata 《Ichthyological Research》2002,49(2):202-205
Mating behavior of the Far Eastern catfish, Silurus
asotus (Siluriformes: Siluridae), was observed in a ricefield system facing the shore of Lake Biwa in mid-May to early June in 1990–1997.
A set behavioral sequence similar to those of two other silurid fishes, S. biwaensis and S. lithophilus, both endemic to the Lake Biwa system, was observed: “chasing,”“clinging,”“enfolding” while “squeezing” by the male, and
“circling” by the spawning pair. This form of mating behavior is quite different from that of S. asotus reported from the Ooi River system in Kyoto Prefecture, which mainly spawns in running water in ditches.
Received: April 10, 2001 / Revised: November 5, 2001 / Accetped: November 20, 2001 相似文献
3.
A. S. Yang 《Insectes Sociaux》2006,53(4):456-462
Nutritional provisioning is a critical component of life history strategies, and of particular interest in social insect colonies
because of the role that division of labor plays in resource allocation. To explore the mechanisms that underlie colony nutritional
strategies, I examined three populations of the ant Pheidole morrisi across a gradient of overwinter food scarcity over two seasons. P. morrisi colonies were found to employ amixed strategy of fat storage with regard to a longer overwinter period: members of both worker
castes increase their percent-fat in a graded manner, while the proportion of a specialized subcaste of majors known as “repletes”,
also increased within the colony. Geographic variation in other colony traits such as mean colony size, mean worker size,
and minor/major caste ratio were also found, although not always in a manner clearly relating to fat storage. These results
indicate that colony demography responds to seasonal fluctuations in food availability through behavioral alterations (increased
fat stores and recruitment of replete workers) rather than physical alterations (changes in lean body sizes or caste ratio).
The findings illustrate the dynamic role division of labor plays in the success of insect colonies confronting environmental
variability.
Received 9 May 2006; revised 19 July 2006; accepted 24 July 2006. 相似文献
4.
Pre-dispersal seed predators of quickly maturing inflorescences of Asteraceae are constrained by shortage of development time.
At seed dispersal, they should pupate or, if still immature, relocate into another inflorescence. To investigate how dominant
coleopteran predators of dandelion seed, Glocianus punctiger (Curculionidae) and Olibrus bicolor (Phalacridae), cope with time limitation we combined observation (development and temperature of dandelion capitulum, thermal
constants of predator development, age structure of larval populations at seed dispersal) and analogy (“rate isomorphy” in
predator development, comparing “model” coleopteran species with similar temperature requirements). Development of a dandelion
capitulum takes 21 days. The time available to G. punctiger (140–190 day degrees, development threshold 6.3°C) is sufficient to complete development and pupate after seed dispersal.
By contrast, only 30–50 day degrees are available to O. bicolor (threshold 13.5°C) and this is not enough to complete development and consequently immature larvae should move to other capitula
to continue feeding until pupation. These contrast strategies which are determined by this thermal adaptation, are accompanied
by differences in larval morphology. The “cold adapted” G. punctiger has an apodous larva not capable of migrating between capitula while the “warm adapted” O. bicolor has a mobile campodeiform larva capable of migration. 相似文献
5.
By regulating both the choice between solitary or collective retrieval and the level of nestmate investment for heavy prey
transport, individual hunters of the ant Gnamptogenys sulcata are able to increase the foraging efficiency of the whole society, despite the extremely small size of this elite group (1
–4 hunters per colony). Their predatory behavior changes according to the static (weight, size, shape) and dynamic (mobility,
escape behaviors) characteristics of the prey. The behavioral sequences resemble those of other poneromorph ants, but palpation
after the approach phase is absent, probably because of the swiftness of the attack. Hunting is always performed by solitary
workers but, independently of prey type and mobility, small, light prey trigger solitary retrieval whereas large, heavy prey
trigger collective retrieval. For intermediate prey weights (8.5 to 21 times the hunter’s weight), some variability in the
strategy choice is encountered. Both static and dynamic factors are involved in assessing the difficulty of handling living
prey as shown by the number of stings delivered by the hunter for prey immobilization. However, the lack of any stinging against
already dead prey indicates that these factors must be uncoupled when selecting retrieval strategies. Prey weight has a major
role in this choice. For a given prey size always triggering solitary retrieval, a two-fold increase in prey weight is sufficient
to trigger collective transport. Conversely, for a given prey size always triggering collective retrieval, a decrease in prey
weight can trigger solitary transport. Moreover, presenting hunters with prey of “infinite” weight triggers several waves
of recruitment, so that the number of recruited workers compensates for the “apparent” prey weight. Despite the inability
to finely match the number of recruits to the weight of retrieved prey, recruitment strategies adopted by G. sulcata may reflect an evolutionary primitive step towards the finely graded recruitment behavior observed in closely related poneromorph
species.
Received 5 February 2007; revised 25 May 2007; accepted 15 June 2007. 相似文献
6.
A method for estimating the complexity of behavioral patterns of ants based on the Kolmogorov complexity is considered. Behavioral
sequences are presented as “texts” compressed with the KGB Archiver (v. 1.2). The elements of behavior (a total of 10) singled
out from video records served as an alphabet. The comparison of “successful” and “incomplete” hunting behaviors in Myrmica rubra showed that successful hunting patterns were characterized by less complexity than “incomplete” ones. It was assumed that
complete patterns had less redundancy and better predictability. The smallest complexity was revealed in complete hunting
patterns of naive (laboratory reared) ants in comparison with members of a natural colony. In perspective, quantitative evaluation
of complexity of behavioral patterns will help to evaluate the level of discrete variability within ant colonies. 相似文献
7.
Over two consecutive years in the North Bank Plain Zone of Assam, India, during the spring growing season (February–June)
of- 2006 and 2007 we examined effects of morpho-physiological characteristics of rice (Oryza sativa L.) plants in relation to methane (CH4) emission from paddy fields. Traditional cultivar “Agni” and modern improved cultivar “Ranjit” were grown in light textured
loamy soil under irrigation. A higher seasonal integrated methane flux (E
sif) was recorded from “Agni” compared to “Ranjit”. Both cultivars exhibited an emission peak during active vegetative growth
and a second peak at panicle initiation. Leaf and tiller number, leaf area, length, and volume of root were greater in “Agni”,
but grain yield and yield-related parameters such as increased photosynthate partitioning to panicles at the expense of roots
were greater in “Ranjit”. “Ranjit” also photosynthesed faster than “Agni” during panicle development but slower than “Agni”
at tillering. In both the years, a higher soil organic carbon content was recorded in plots of “Agni”. Our results suggest
that in “Agni” enhanced diversion of photosynthate to roots resulted in more substrate being available to methanogenic bacteria
in the rhizosphere. Additionally, the more extensive vegetative growth of this cultivar may enhance methane transport from
the soil to the above-ground atmosphere. 相似文献
8.
Males of the seed bug Togo hemipterus are larger in size and have considerably larger front legs compared to females. This size discrepancy is likely related to
the fact that males fight for food using their enlarged forelegs. A “hungry” bug, i.e. one previously without food, is expected to behave in a certain way when food is present. Here, we demonstrate that aggressive
“fighting and chasing” behavior was frequently observed only between males under starvation conditions and became especially
severe when food was present. Togo hemipterus males may adopt a resource-defense mating system that is beneficial for males because females aggregate near food when it
is scarce. This strategy strongly suggests that the aggressive behavior acts as male–male competition. In a second set of
experiments, aggressive behavior occurred between two small males, two large males, or one large and one small male. Fighting
ensued mainly when large males were involved, and larger males won fights. Consequently, the male-biased sexual size dimorphism
in T. hemipterus appears to be partially attributable to sexual selection favoring larger males. 相似文献
9.
R. M. Feitosa 《Insectes Sociaux》2007,54(2):200-201
Disturbance of W. auropunctata colonies first produced, as expected, significant dispersal of workers and queens, but this was soon followed by a radiate
aggregation of workers, heads to center, in groups of 5 – 8 individuals, all with mandibles widely open. Queens did not aggregate,
but instead searched for the grouped workers, antennating the gaster of a selected individual; after this, workers began to
slowly board onto the queen’s body. This behavior was repeated with other groups, until the queen could not bear any more
workers. This behavior is registered for the first time for adult ants, and is interpreted as a unique strategy to reorganize
the nest or to establish a new colony. The open mandibles may indicate the release of alkylpyrazine, a known aggregation pheromone.
Received 8 January 2007; revised 28 February 2007; accepted 2 March 2007. 相似文献
10.
The odorous house ant, Tapinoma sessile, is a native ant species common throughout North America. In urban areas, this ant is classified a pest species and exhibits
several attributes characteristic of invasive “tramp” ants (sensu Passera, 1994). These include: extreme polygyny, colony
reproduction by budding, reduced internest aggression, generalist diet, and polydomy. Here we explore the organization of
foraging and the pathways of food distribution in polydomous colonies of T. sessile in the laboratory and field using a novel marking technique (rabbit IgG protein) and enzyme linked immunosorbent assay (ELISA).
Laboratory assays revealed patterns of food allocation from foragers to other castes and developmental stages. Foragers distributed
the IgG- labelled sucrose to the majority of workers within 24 h, and workers retained significantly more sucrose than either
queens or larvae. Approximately 50% of queens tested positive for the IgG marker and some queens received significantly more
sucrose than others, indicating a possible reproductive dominance hierarchy. Larvae received little sucrose demonstrating
their minor reliance on carbohydrates. The results of field experiments showed that odorous house ants are dispersed central-place
foragers whereby ants from individual nests exhibit high foraging site fidelity, travel along well-established trails, and
forage on a local scale. Dispersed central-place foraging most likely allows the odorous house ant to more efficiently secure
both clumped and dispersed food sources and possibly increases its competitive ability. As a result, colonies become numerically
large and ecologically dominant. The results of our study contribute to our understanding of the social behavior and colony
organization in T. sessile. In addition, they provide a framework for designing more effective ant control programs based on liquid baits.
Received 13 December 2005; revised 28 February 2006; accepted 3 March 2006. 相似文献
11.
Liparidae from stomachs of Antarctic toothfish Dissostichus mawsoni Norman, 1937 (Nototheniidae) caught in the Ross Sea (Pacific sector of Antarctica) have been identified. Two new species
of deep-water liparids of the genus Paraliparis Collett, 1879—P. caninus sp. nov. (at a depth of 1182–1651 m) and P. vipera sp. nov. (1700 m)—were described. Both species that turned out to be most similar to P. neelovi Andriashev, 1982, from the Kerguelen area (the Indo-Oceanic sector of the South Ocean) are combined with it into a species
group “P. neelovi.” According to meristic characters, pattern of dentition, and the size of gill opening, species of “P. neelovi” are close to the species group “P. copei.” In collections from a depth of 1700 m, also two individuals of P. andriashevi Stein et Tompkins, 1989, known previously from only two types from the northern boundary of the Ross Sea were found. The
new finding supports species validity and extends the known limits of its range. The wide distribution of bathybenthal Paraliparis having low fecundity and leading a near-bottom mode of life can be explained by the presence of mesopelagic juveniles and
their dispersal via currents. 相似文献
12.
Disanthus cercidifolius Maxim. var. longipes H.T. Chang usually has two inflorescences growing in opposite directions in the axillae, but occasionally three inflorescences
grow paratactically. The typical flowering process could be divided into 4 periods: “Pre-dehiscence”, “Initial dehiscence”, “Full dehiscence” and “Withering”. Both the natural population and the planted population had a flowering peak of 15–35 days after the first flower bloomed.
There were significant differences between the time courses of flowering of the two populations. Out-crossing is the main
breeding system in this species. And autogamy decreases the risk of reproductive failure of this species. The main insect
pollinators of D. cercidifolius var. longipes are Episyrphus balteatus de Geer, Scaptodrosophila coracina Kikkawa and Peng, Polistes olivaceus de Geer, Apis cerana Fabricius, Nezara viridula L. and Coccinella septempunctata L., and so on. Among the insects, S. coracina and E. balteatus are the most important and efficient pollinators, but others are inefficient pollinators. Though wind pollination is not
efficient, it guarantees reproduction when insect pollinators are not available. “Mass flowering” is an adaptive behavior and reproductive strategy of this species, and “few fruiting” could be caused by the lack of pollinators. 相似文献
13.
New species of Pogonophryne (Pisces, Artedidraconidae) from the Bellingshausen Sea, Antarctica 总被引:1,自引:1,他引:0
A new species of notothenioid fish, Pogonophryne bellingshausenensis n. sp., is described from the Bellingshausen Sea, Antarctica. The new species belongs to the dorsally-spotted “mentella”
group of the genus and is characterized by having a short (about 13% SL) mental barbel with a short (about 16% of barbel length),
narrow (barely wider than the stalk), and relatively inconspicuous terminal expansion composed of short, irregular, fingerlike
processes. Compared to most other dorsally-spotted species of Pogonophryne (“barsukovi”, “marmorata”, and “mentella” groups), P. bellingshausenensis has a relatively wide (about 7% SL) interorbital region. An unspotted patch on the median dorsal surface of the head, posterior
to the posttemporal ridges and anterior to the first dorsal fin, has not been observed previously in any dorsally-spotted
species. The holotype was collected at 1,947 m, one of the deepest records for any species of Pogonophryne. A revised key to the ten species of the “mentella” group of Pogonophryne is also provided. 相似文献
14.
N. Rashevsky 《Bulletin of mathematical biology》1969,31(4):789-795
The author's theory of the adoption of certain types of behavior patterns (Rashevsky, N., 1957, “Contributions to the Theory
Initiative Behavior”.Bull. Maths. Biophysics,19, 91–119; 1968,Looking at History through Mathematics, Cambridge, Massachusetts: M.I.T. Press) consisting of elementary behaviors for each of which there is an opposite one and
the two are mutually exclusive, is applied to describe the changes in the general type of behavior of a society. The elementary
acts of which the whole problem consists may be either overt activities or beliefs or opinions. The general behavior patternsadopted by the society are considered as the “proper” or “just” ones. Any deviation from it in either one or more of the component
elementary behaviors is considered as “unjust” and is subject to some punitive action. The total number of possible mutually
exclusive behavior patterns is very large but finite. Within this very large range of possible patterns, we find that this
notion of justice is relative, because changes from any behavior pattern to any other may occur. It is further shown that
the amount of punishment for the deviation from the accepted pattern in order to be effective as well as efficient must be
applied in different ways to different individuals even for the same transgression. 相似文献
15.
To elucidate the potential for colony growth and the dispersal of aphids in relation to the ant attendance, the mobility,
tolerance of starvation, colony growth, and dispersal were examined in the ant-tended Aphis craccivora Koch and the non-ant-tended Acyrthosiphon pisum Harris under the absence of predators and ants. The increase of the dispersal rate with density was more conspicuous in Ac. pisum than Ap. craccivora. The success rate of dispersal was higher in Ac. pisum than Ap. craccivora. These results would be derived from the higher ability of dispersal by walking in Ac. pisum than Ap. craccivora. The longer legs, higher walking speed, and stronger tolerance of starvation in Ac. pisum might result in a higher ability of dispersal by walking. These traits may have developed in relation to non-ant attendance,
because Ac. pisum aphids frequently escape from natural enemies by dropping from the host plant. On the other hand, Ap. craccivora have not developed morphological and behavioral traits concerning dispersal by walking, because increasing colony size without
dispersal is likely to be advantageous for ant attraction. Escaping behaviors of Ap. craccivora from natural enemies have not been well developed due to the ant’s defense against natural enemies. The proportion of alatae
in Ap. craccivora was higher than in Ac. pisum instead of a lesser ability for dispersal by walking in Ap. craccivora. The differences in ant attendance have been influenced in the development of morphological and behavioral traits concerning
the dispersal ability, and then, different potentials for reproduction and dispersal have developed in ant-tended aphids and
non-ant-tended aphids. 相似文献
16.
George D. Koufos Louis de Bonis Dimitris S. Kostopoulos Laurent Viriot Theodora D. Vlachou 《Pal?ontologische Zeitschrift》2004,78(1):213-228
Two skulls, two mandibles and some postcranials ofMesopithecus from the locality “Vathylakkos 2” of Axios Valley (Macedonia, Greece) enlarge our knowledge about the genus and its differentiation.
The new material together with an old skull from the same locality is compared with the Pikermi, “Ravin des Zouaves 5” (Axios
Valley), and Maramena (Serres basin) samples. It is concluded that the VathylakkosMesopithecus resemblesM. pentelicus from Pikermi, as wellM. delsoni from “Ravin des Zouaves 5” and it is referred asMesopithecus sp. aff.M. pentelicus. The biochronological age of “Vathylakkos 2” has been considered as MN 12, while recent magnetostratigraphic data indicate
an age of about 7.5 Ma. This age confirms the position of the VathylakkosMesopithecus between Pikermi and “Ravin des Zouaves 5”. Some dental indices compared with those of the RecentCercopithecus suggest that the Vathylakkos sample is monospecific.
相似文献
17.
Patrizia-I Politi Kyriacos Georghiou Margarita Arianoutsou 《Trees - Structure and Function》2011,25(4):655-668
The reproductive biology of the endemic to Greece Abies cephalonica Loudon, including the phenology of the reproductive life cycle, cone production in relation to plant age and the required
seed germination conditions, was studied. All individuals growing within 20 permanent plots of 100 m2 each established in 11 different locations covering the entire strictly protected area of Mount Aenos National Park (Cephalonia)
were monitored over a period of 4 years. The cones are formed on the upper part of the previous year’s branches, mostly at
the upper crown half of the reproductive individuals (over 53 years old). Female flowers are pollinated in spring and cone
maturation lasts until the beginning of autumn, when seed dispersal occurs. The annual production of cones per individual
varied significantly, revealing masting behavior for this tree. This behavior was also expressed in the number of trees producing
cones, as well as the percentage of sound seeds per cone. A significant difference in the mass and the length of the cones
between the years of low and high cone production was observed, being higher in the years of massive cone production. Similar
germination percentages were observed in full darkness or under “canopy light” and “sun light”, provided that the seeds were
previously stratified for 6 weeks. It is concluded that A. cephalonica exhibits plasticity expressed in its reproductive behavior for alternating years of high to low cone production and in its
seed germination for an array of habitat light conditions. 相似文献
18.
We propose a simple experiment to study delocalization and extinction in inhomogeneous biological systems. The nonlinear
steady state for, say, a bacteria colony living on and near a patch of nutrient or favorable illumination (“oasis”) in the
presence of a drift term (“wind”) is computed. The bacteria, described by a simple generalization of the Fisher equation,
diffuse, divide A→A + A, die A→ 0, and annihilate A + A→ 0. At high wind velocities all bacteria are blown into an unfavorable region (“desert”), and the colony dies out. At low
velocity a steady state concentration survives near the oasis. In between these two regimes there is a critical velocity at
which bacteria first survive. If the “desert” supports a small nonzero population, this extinction transition is replaced
by a delocalization transition with increasing velocity. Predictions for the behavior as a function of wind velocity are made
for one and two dimensions.
Received: 3 August 1998 / Revised version: 17 July 1999 / Published online: 4 July 2000 相似文献
19.
A quantum model for the general enzymic reaction,E+S ⇌ ES → P, is presented, starting with the assumptions that any chemical substanceS, which may be a substrate for a particularE
(S)-enzyme is a microphysical system and any enzymeE-molecule, capable of interacting with anS-substrate is a “measuring system” which will “measure” one or more of theS-observables. According to the above assumptions a stochastic model of the reaction is constructed and a computer simulation
of the steady state performed. The results thus obtained predicted fluctuations in the enzymic reaction rate, function of
the substrate “perturbation”.
On an experimental basis it is demonstrated that the irradiation of an enzymic substrate with low energies results in the
inducement of a dose-dependent oscillatory behavior in the corresponding enzymic reaction rate.
In the
reaction type, the oscillations thus induced in theE-activity by the corresponding substrates are out-of-phase, realizing a biochemical discriminating net. Likewise, in an
reaction type, the oscillations induced by the irradiatedS-substrate in the activities of the respective enzyme, realize a biochemical switching net. 相似文献
20.
T. Shivashankar 《Journal of biosciences》1994,19(1):81-90
Scorpions arc generally non-social, solitary animals that interact with conspecifics at birth, courtship or predation only.
The present study reports the presence of advanced sub social behaviour inHeterometrus fulvipes Brunner and evaluates the importance of its burrowing as a cause for such social behaviour.Heterometrus fulvipes constructed deep angular burrows at the base of plants. Burrows provided (i) protection against predation, (ii) increased
availability of food and (iii) ideal microclimate for year round activity of the scorpions. No cannibalism was observed in
laboratory maintained colonies. The risk of predation and the difficult by immatures to dig tunnels during dry soil conditions
may have forced the mother and offspring to live together in the burrow for longer durations. The cohabitation of relative
offsprings transforms the burrow into a nest. The members of a colony exhibits division of labour for nest expansion and in
foraging. The mother communicates with the immatures through “Buzz” sound and may provide premasticated food. There is food
sharing also among colony members. All these behaviours indicate the presence of advanced sub social behaviour inHeterometrus fulvipes. 相似文献