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1.
Peggy S. M. Hill 《Die Naturwissenschaften》2009,96(12):1355-1371
Animal communication is a dynamic field that promotes cross-disciplinary study of the complex mechanisms of sending and receiving
signals, the neurobiology of signal detection and processing, and the behaviors of animals creating and responding to encoded
messages. Alongside visual signals, songs, or pheromones exists another major communication channel that has been rather neglected
until recent decades: substrate-borne vibration. Vibrations carried in the substrate are considered to provide a very old
and apparently ubiquitous communication channel that is used alone or in combination with other information channels in multimodal
signaling. The substrate could be ‘the ground’, or a plant leaf or stem, or the surface of water, or a spider’s web, or a
honeybee’s honeycomb. Animals moving on these substrates typically create incidental vibrations that can alert others to their
presence. They also may use behaviors to create vibrational waves that are employed in the contexts of mate location and identification,
courtship and mating, maternal care and sibling interactions, predation, predator avoidance, foraging, and general recruitment
of family members to work. In fact, animals use substrate-borne vibrations to signal in the same contexts that they use vision,
hearing, touch, taste, or smell. Study of vibrational communication across animal taxa provides more than just a more complete
story. Communication through substrate-borne vibration has its own constraints and opportunities not found in other signaling
modalities. Here, I review the state of our understanding of information acquisition via substrate-borne vibrations with special
attention to the most recent literature. 相似文献
2.
Caterpillars have many natural enemies and, therefore, have evolved a diversity of antipredator strategies. Most research
focuses on those strategies (crypsis, countershading, and warning coloration) targeting visually guided predators. In contrast,
defensive sounds, although documented for more than a century, have been poorly studied. We report on a novel form of sound
production—chirping—in caterpillars of the common European Great Peacock moth (Saturnia pyri). Chirps are broadband, with dominant peaks ranging between the sonic (3.7 kHz) and ultrasonic (55.1 kHz) and are generated
by a rapid succession of mandibular “tooth strikes.” Chirp trains are induced by simulated predator attacks and precede or
accompany the secretion of a defensive chemical from integumental bristles, supporting our hypothesis that these sounds function
in acoustic aposematism. We propose that these caterpillars generate multimodal warning signals (visual, chemical, and acoustic)
to target the dominant sensory modalities of different predators, including birds, bats, and invertebrates.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
3.
The evolution of winged stick insects (phasmids) from secondarily wingless ancestors was proposed in recent studies. We explored
the cuticle of flying phasmids for wind sensors that could be involved in their flight control, comparable to those known
for locusts. Surprisingly, wind-sensitive hairs (wsH) occur on the palps of mouthparts and on the antennae of the winged phasmid
Sipyloidea sipylus which can fly in tethered position only when air currents blow over the mouthparts. The present study describes the morphology
and major functional properties of these “new” wsH with soft and bulging hair bases which are different from the beaker-like
hair bases of the wsH on the cerci of phasmids and the wsH described in other insects. The most sensitive wsH of antennae
and palps respond with phasic-tonic afferents to air currents exceeding 0.2 ms−1. The fields of wsH on one side of the animal respond mainly to ventral, lateral, and frontal wind on the ipsilateral side
of the head. Afferent inputs from the wsH converge but also diverge to a group of specific interneurons at their branches
in the suboesophageal ganglion and can send their integrated input from wsH fields of the palps and antennae to the thoracic
central nervous system. Response types of individual wsH-interneurons are either phasic or phasic-tonic to air puffs or constant
air currents and also, the receptive fields of individual interneurons differ. We conclude that the “new” wsH system and its
interneurons mainly serve to maintain flight activity in airborne phasmids and also, the “new” wsH must have emerged together
with the integrating interneurons during the evolution from wingless to the recent winged forms of phasmids. 相似文献
4.
The leafhopper Scaphoideus titanus is the vector of a major phytoplasma grapevine disease, Flavescence dorée. The vector’s distribution is in Eastern and Northern
Europe, and its population dynamics varies as a function of vineyard latitude. We tested the hypothesis that hatching dynamics
are cued by cold temperatures observed in winter. We exposed eggs from a natural population to simulated “cold” and “mild”
winters and varied the exposure time at 5 °C from 0 to 63 days. We show that temperature cooling mainly affected the onset
of hatching and is negatively correlated to the cold time exposure. The majority of hatchings occurred more quickly in cold
rather than in mild winter simulated conditions, but there was no significant difference between the duration of hatching
of eggs whatever the cold time exposure. In agreement with the Northern American origin of the vector, the diapause termination
and thus the timing regulation of egg hatching require cold winters. 相似文献
5.
Living in a “stethoscope”: burrow-acoustics promote auditory specializations in subterranean rodents
Subterranean mammals rely to a great extent on audition for communication and to be alerted to danger. The only hitherto published
report on burrow acoustics revealed that in tunnels of blind mole-rats (Spalax ehrenbergi), airborne sounds of 440 Hz propagated best whereas lower and higher frequencies were effectively attenuated. Morpho-functional
analyses classify the ear of subterranean mammals as a low-sensitivity and low-frequency device. Concordantly, hearing is
characterized by low sensitivity and a restricted frequency range tuned to low frequencies (0.5–4 kHz). Some authors considered
the restricted hearing in subterranean mammals vestigial and degenerate due to under-stimulation. In contrast to this view
stand a rich (mostly low-frequency) vocal repertoire and progressive structural specializations of the middle and inner ear.
Thus, other authors considered these hearing characteristics adaptive. To test the hypothesis that acoustical environment
in burrows of different species of subterranean mammals is similar, we measured sound attenuation in burrows of Fukomys mole-rats (formerly known as Cryptomys, cf. Kock et al. 2006) of two differently sized species at different locations in Zambia. We show that in these burrows, low-frequency sounds (200–800 Hz)
are not only least attenuated but also their amplitude may be amplified like in a stethoscope (up to two times over 1 m).
We suggest that hearing sensitivity has decreased during evolution of subterranean mammals to avoid over-stimulation of the
ear in their natural environment.
We dedicate this work to Mathias Kawalika, who died in March 2006. 相似文献
6.
Flowers adapted for hummingbird pollination are typically red. This correlation is usually explained by the assertion that
nectar- or pollen-stealing bees are “blind” to red flowers. However, laboratory studies have shown that bees are capable of
locating artificial red flowers and often show no innate preference for blue over red. We hypothesised that these findings
might be artefacts of the simplified laboratory environment. Using bumblebees (Bombus impatiens) that had been trained to visit red and blue artificial flowers, we tested whether colour preference was influenced by complexity
of the background on which they were foraging. Many bees were indifferent to flower colour when tested using a uniform green
background like those commonly used in laboratory studies, but all bees showed strong colour preferences (usually for blue)
when flowers were presented against a photograph of real foliage. Overall, preference for blue flowers was significantly greater
on the more realistic, complex background. These results support the notion that the red of “hummingbird syndrome” flowers
can function to reduce bee visits despite the ability of bees to detect red and highlight the need to consider context when
drawing inferences about pollinator preferences from laboratory data.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
7.
Wolfgang Wiltschko Lars Dehe Katrin Stapput Peter Thalau Roswitha Wiltschko 《Die Naturwissenschaften》2010,97(1):37-42
Under 502 nm turquoise light combined with 590 nm yellow light and in total darkness, European robins, Erithacus rubecula, no longer prefer their migratory direction, but exhibit so-called fixed direction responses that do not show the seasonal
change between spring and autumn. We tested robins under these light conditions in the local geomagnetic field of 46 μT, a
field of twice this intensity, 92 μT, and a field of three times this intensity, 138 μT. Under all three magnetic conditions,
the birds preferred the same easterly direction under turquoise-and-yellow light and the same northwesterly direction under
dark, while they were oriented in their seasonally appropriate direction under control conditions. “Fixed direction” responses
are thus not limited to a narrow intensity window as has been found for normal compass orientation. This can be attributed
to their origin in the magnetite-based receptor in the upper beak, which operates according to fundamentally different principles
than the radical pair mechanism in the retina mediating compass orientation. “Fixed direction” responses are possibly a relict
of a receptor mechanism that changed its function, now mainly providing information on magnetic intensity. 相似文献
8.
Global change, i.e. the mega-process radically transforming the relationship between nature and human civilization since
the end of World War II, is investigated from the point of view of systems analysis. It is argued that this unbridled process
should rather be domesticated by planetary control strategies transpiring from a new science called “geocybernetics”. The
formal aspects of geocybernetic theory are sketched and illustrated in a tutorial theatre world reflecting the overall environment
and development problematic. Within this setting a straightforward operationalization of the sweeping “sustainable development”
ideal through a set of concise paradigms can be achieved. Evidence is provided that geocybernetics is actually feasible on
the basis of earth system modelling and fuzzy-control techniques. 相似文献
9.
Laura Rodríguez-Loeches Alejandro Barro Martha Pérez Frank Coro 《Die Naturwissenschaften》2009,96(4):531-536
Both sexes of Phoenicoprocta capistrata have functional tymbals. The scanning electron microscopy revealed differences in the morphology of these organs in males
and females. Male tymbals have a well-developed striated band, constituted by 21 ± 2 regularly arranged striae whereas female
tymbals lack a striated band. This type of sexual dimorphism is rare in Arctiidae. The recording of the sound produced by
moths held by the wings revealed that while males produced trains of pulses organized in modulation cycles, females produced
clicks at low repetition rate following very irregular patterns. Statistically, there are differences between sexes in terms
of the duration of pulses, which were 355 ± 24 μs in the case of males and 289 ± 29 μs for females. The spectral characteristics
of the pulses also show sexual dimorphism. Male pulses are more tuned (Q
10 = 5.2 ± 0.5) than female pulses (Q
10 = 2.7 ± 0.5) and have a higher best frequency (42 ± 1 kHz vs. 29 ± 2 kHz). To our knowledge, this is the first report on
an arctiid moth showing sexual dimorphism in tymbal’s anatomy that leads to a best frequency dimorphism. Males produce sound
at mating attempts. The sounds recorded during mating are modulation cycles with the same spectral characteristics as those
recorded when males are held by the wings. The morphological and acoustic features of female tymbals could indicate a process
of degeneration and adaptation to conditions under which the emission of complex patterns is not necessary.
Frank Coro no longer works at Universidad de La Habana. 相似文献
10.
M. A. Castillo-Santiago A. Hellier R. Tipper B. H. J. de Jong 《Mitigation and Adaptation Strategies for Global Change》2007,12(6):1213-1235
This study examines the correlation between deforestation, carbon dioxide emissions and potential causal factors of land-use
change within an area of 2.7 million ha in Chiapas, southern Mexico between 1975 and 1996. Digitized land-use maps and interpreted
satellite images were used to quantify land-use changes. Geo-referenced databases of population and digitized maps of roads
and topography were used to determine which factors could be used to explain observed changes in land-use. The study analyzed
the relationship between carbon emissions during this period and two types of possible causal factors: “predisposing” factors
that determine the susceptibility of a particular area of forest to change (slope, distance to agriculture and roads, land
tenure) and “driving” factors representing the pressures for change (population density, poverty). The correlated factors
were combined in risk matrices, which show the proportion of vulnerable carbon stocks lost in areas with defined social, economic
and environmental characteristics. Such matrices could be used to predict future deforestation rates and provide a verifiable
evidence-base for defining baseline carbon emissions for forest conservation projects. Based on the results of the analysis,
two matrices were constructed, using population density as the single most important driving factor and distance from roads
and distance from agriculture as the two alternatives for the predisposing factors of deforestation. 相似文献
11.
Social harmony often relies on ritualised dominance interactions between society members, particularly in queenless ant societies,
where colony members do not have developmentally predetermined castes but have to fight for their status in the reproductive
and work hierarchy. In this behavioural plasticity, their social organisation resembles more that of vertebrates than that
of the “classic” social insects. The present study investigates the neurochemistry of the queenless ant species, Streblognathus peetersi, to better understand the neural basis of the high behavioural plasticity observed in queenless ants. We report measurements
of brain biogenic amines [octopamine, dopamine, serotonin] of S. peetersi ants; they reveal a new set of biogenic amine influences on social organisation with no common features with other “primitively
organised societies” (bumble bees) and some common features with “highly eusocial” species (honey bees). This similarity to
honey bees may either confirm the heritage of queenless species from their probably highly eusocial ancestors or highlight
independent patterns of biogenic amine influences on the social organisation of these highly derived species. 相似文献
12.
Several stages, from eggs to adults, of the water strider, Aquarius paludum (Fabricius), inhabiting fresh water are sometimes conveyed by heavy flow in the rainy or typhoon seasons in Japan to lotic
brackish water in the mouth of rivers. The water striders might then respond to salinity either by remaining to wait for extensive
rainfall to reduce osmotic pressure locally before reproducing (“breed here and later tactic”) or by flying away to reproduce
in fresh waters elsewhere (“breed elsewhere and later tactic”). All first instars died before the first molt when they were
exposed to 1.75 and 3.5% NaCl solutions in a laboratory experiment. Living on 0.5 and 0.9% solutions through larval and adult
stages slowed down larval growth and suppressed female reproduction. When exposed to the 0.5 and 0.9% solutions, 90 and 92%
of males, respectively, showed histolysis of their flight muscles. Therefore, in brackish natural habitats, larvae and adults
seem to follow the strategy “breed here and later.” When water striders were exposed to 0.9% solution either just after emergence
or 20 days later, females showed a higher flight propensity than those kept on fresh waters throughout, and they delayed the
deposition of eggs. Therefore, when conveyed to brackish water after emergence by stream flow after heavy rain, adults seem
to leave the area by flight, demonstrating the strategy “breed elsewhere and later” tactic. We conclude that water striders
use alternative tactics for responding to salinity, depending on the stage of exposure. 相似文献
13.
14.
Strategic 3-hydroxy-2-butanone release in the dominant male lobster cockroach, <Emphasis Type="Italic">Nauphoeta cinerea</Emphasis> 总被引:3,自引:1,他引:2
In the lobster cockroach Nauphoete cinerea, the dominant–subordinate hierarchy formed via the agonistic interactions is unstable, and changes in rank order are common.
Our previous results showed that in the first encounter fight during initial rank formation, microgram levels of 3H-2B are
released by the aggressive posture (AP)-adopting dominant male. In the present study, the pattern of daily pheromone (3H-2B)
release during the domination period and on the day of rank switch, rank duration, and rank switch frequency were investigated
in three-male groups and six-male groups to examine the effect of higher frequency of agonistic encounters. The results showed
that, in the three-male groups (50-day observation period), daily 3H-2B release rate was not constant, but fluctuated, the
average duration of dominant rank was 16.6 ± 2.0 days, rank switch occurred in 58.8% of groups, and the frequency of rank
switching (average number of rank switches/group/50 days) was 1.4 ± 0.2. For the six-male groups (30-day observation period),
the daily 3H-2B release rate also fluctuated, but the duration of dominant rank was significantly shorter at 4.2 ± 0.6 days,
rank switch occurred in 100% of groups, and the frequency of rank switching (average number of rank switches/group/30 days)
was significantly higher at 6.9 ± 0.6. The results for both sets of male groups showed that as a new rank formed (either on
the first encounter day or on the day of rank switching), the dominant status was significantly associated with a higher 3H-2B
release rate. In the animal kingdom, fighting usually involves communication or the exchange of signals, and the results of
this study indicated that the fluctuating daily 3H-2B release rate adopted by the dominants is a kind of strategic release
and the 3H-2B release rate is a signal used to determine dominance. 相似文献
15.
The intertidal midge Clunio, which reproduces on exposed rocky seashores, becomes enclosed in an irregularly shaped air bubble during short submersion
by incoming waves. This water-repellent property of Clunio’s cuticle is caused by a complete cover of hydrophobic microtrichia offering an effective surf tolerance. These microtrichia
not only trap a thin air layer above the cuticle but also maintain a larger air bubble between the insect’s ventral side and
legs. The effectiveness of the water repellence was quantitatively characterised on the basis of a known model (Crisp and
Thorpe, Discuss Faraday Soc 3:210–220, 1948). The parameters of the model are the contact angle θ (>90°) at the contact line of air/water/microtrichia and the distance between individual microtrichia and their radius. When
the microtrichia are 1.1 μm apart and have a radius of 0.1 μm and an estimated contact angle θ of 140°, the air layer is stable against hydrostatic pressures of up to 3 m water column. As shown by a modified version
of the model, considerably larger air bubbles can be trapped by the microtrichia cover of the legs up to distances of 0.5 mm
from the body. The widely spaced (about 8 μm apart) and longer setae of Clunio are not involved in the formation of air layers and air bubble. 相似文献
16.
17.
In an attempt to better understand the mechanism underlying lateral collision avoidance in flying insects, we trained honeybees
(Apis mellifera) to fly through a large (95-cm wide) flight tunnel. We found that, depending on the entrance and feeder positions, honeybees
would either center along the corridor midline or fly along one wall. Bees kept following one wall even when a major (150-cm
long) part of the opposite wall was removed. These findings cannot be accounted for by the “optic flow balance” hypothesis
that has been put forward to explain the typical bees’ “centering response” observed in narrower corridors. Both centering
and wall-following behaviors are well accounted for, however, by a control scheme called the lateral optic flow regulator, i.e., a feedback system that strives to maintain the unilateral optic flow constant. The power of this control scheme is
that it would allow the bee to guide itself visually in a corridor without having to measure its speed or distance from the
walls. 相似文献
18.
Minerals on earth whose crystalline order has been reduced by radioactive decay of contained atoms are termed “metamict.”
They are rare and few because in most crystalline solids, atoms and vacancies are relatively mobile at terrestrial temperatures,
and radiation damage tends to be self-annealing. This is not the case in the extreme cold of deep space. Below roughly 100 K,
reduced vacancy mobility allows cosmic ray and solar wind induced lattice defects to endure and accumulate for eons, reaching
energy densities of up to MJ kg−1 in some materials. We examine the possible effects of the release of energy stored in cold deep-space materials when solid-state
defects recombine upon warming due to impacts, gravitational infall, or perihelion. Dimensional analysis suggests energetic
defect recombination in radiation-damaged “xenomict” solids in comets, and planetesimals may, in some circumstances, raise
internal temperatures enough to melt ice and volatilize frozen gases. We speculate that this may account for some cometary
outbursts and Deep Impact experiment results. Calorimetric experiments on appropriately irradiated natural and synthetic materials
are needed to further quantify these mechanisms. 相似文献
19.
Kohko Tokushige Keigo Akimoto Toshimasa Tomoda 《Mitigation and Adaptation Strategies for Global Change》2007,12(7):1237-1251
CO2 geological storage will be one of the cost-effective options for global warming mitigation, and this technology is under
development widely in the world. However, the technology may face the challenge of public acceptance before its implementation.
In order to evaluate the public acceptance, questionnaire surveys were conducted among Japanese university students. A cognitive
map of geological storage, together with other major global warming mitigation options, everyday life activities, etc., was
constructed by means of a statistical analysis of the responses to the questionnaire. The risk-benefit cognitive map consists
of the following factors: “risk perception,” “benefit perception,” and “public acceptance.” The risk perception is further
disaggregated into “dread risk” and “unknown risk.” Additionally, a second survey was conducted after providing the students
with additional information on global warming and CO2 geological storage, and the effects of the information on their perceptions were evaluated. The effects of risk and benefit
perceptions on public acceptance were evaluated and discussed based on the cognitive maps representing the perceptions before
and after providing the information. The analyses revealed that the benefit perception was more influential than the risk
perception on the public acceptance of CO2 geological storage. The benefit perception increased greatly after providing the information; however, the unknown risk remained
considerably large. Further, RD&D relating unknown risk, for example, the monitoring technology for stored CO2 and the risk assessment of CO2 leakage, and the supply of related information to the public would be beneficial for increasing the public acceptance. 相似文献
20.
Sexually aberrant individuals, displaying both male and female characteristics, are rare in occurrence but are documented
throughout the animal kingdom. In parasitoid wasps of the genus Trichogramma, such individuals typically appear as a result of rearing Wolbachia-infected thelytokous wasps at high temperatures. Sexually aberrant Trichogramma have been referred to interchangeably in the literature as gynandromorphs, sexual mosaics and intersexes. However, accurately
used, the terms “gynandromorph” and “sexual mosaic” describe an individual composed of a mixture of genetically distinct tissues
corresponding to the sexual phenotypes observed, while “intersex” refers to an individual having a uniform genetic constitution
but with some tissues exhibiting sexual phenotypes conflicting with the associated genotype. Here, we investigate the heat-induced
production of sexually aberrant offspring by thelytokous Trichogramma kaykai. Aberrant individuals were rare, but each was characterized as one of 11 morphotypes ranging from very feminine to very masculine.
Overall, the production of aberrant individuals increased with time from the onset of maternal oviposition. However, while
the production of males also increased with time, the degree of masculinity of aberrant individuals did not; the different
morphotypes appeared to be produced haphazardly. We conclude that the aberrant individuals produced by T. kaykai are actually intersexes and not gynandromorphs. The wasp's close association with Wolbachia and the absence of intersexes in uninfected populations allow us to discuss a possible origin of the condition. 相似文献