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81.
Kazuo Fujita Kunio Watanabe Tri Heru Widarto Bambang Suryobroto 《Primates; journal of primatology》1997,38(3):233-245
A series of work by the first author have demonstrated that many macaque species show a visual preference for the pictures
of their own species when the monkeys actively press a lever to see the pictures. We expanded this study to Sulawesi macaques
kept as a pet by local people with slight modification. All seven species of Sulawesi macaques were passively exposed to a
variety of colored slides of Sulawesi macaques. The experimenter recorded the duration of visual fixation onto the pictures.
Male monkeys of all the seven species clearly watched the pictures of their own species for longer duration than those of
the other species. Such visual preference suggested that the seven Sulawesi macaques discriminate each other species and,
thus, they may not be integrated into fewer number of species. This visual preference may work to prevent overall intergradation
of the Sulawesi macaques who sometimes have hybrid zones only in limited areas. This preference was in general weaker in female
monkeys. In one species,Macaca ochreata, females actively avoided to see the pictures of conspecifics. These results may be related to how female monkeys interact
with other individuals. 相似文献
82.
We experimentally investigated the attraction of adult butterflies to moist soil and dirt places (a behavior termed `mud-puddling')
in two species-rich tropical communities on the island of Borneo. At a rain forest site, 227 individuals (46 species) were
attracted to the baits, compared to 534 individuals (54 species) at a farmland site. With one single exception, all attracted
butterflies were males. Of various salt and amino acid solutions, only sodium was accepted, but overall, albumin solutions
turned out to be the most attractive puddling resource. Butterfly families differed consistently in their resource preferences.
Representatives of the families Papilionidae and Pieridae more often visited NaCl solutions, but still accepted albumin, whereas
representatives of the Nymphalidae, Hesperiidae and, in particular, Lycaenidae preferred the protein resource. In experiments
using decoys prepared from pinned butterfly specimens, representatives of the Papilionidae and Pieridae were more strongly
attracted to baits provided with decoys made from conspicuous, medium-sized yellow Eurema species (Pieridae), whereas dummies made from small, cryptically colored lycaenids (Prosotas and Caleta species) were ineffective. Decoys did not influence the attraction of lycaenid butterflies towards baits. Hence, visual cues
play an important role in locating puddling resources for papilionids and pierids, while for lycaenid butterflies searching
for nitrogen sources, olfactory cues emitted by decaying organic matter are more likely to be important. The strong attraction
of male butterflies to nitrogen-rich resources suggests that, as in the case of sodium, these nutrients may increase reproductive
success.
Received: 5 October 1998 / Accepted: 7 December 1998 相似文献
83.
A. E. Dontsov I. B. Fedorovich M. Lindström M. A. Ostrovsky 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1999,169(3):157-164
Retinal visual and screening pigments of two populations (one marine and the other freshwater) of the opossum shrimp Mysis relicta Lovén (Crustacea, Mysidacea), which have different ocular tolerance to light, was investigated. Visual pigments were extracted
by detergent and their bleaching difference spectra were determined. The difference between the visual pigment absorption
maximum of the two populations correlated with their difference in spectral sensitivity. Using buffer or neutral methanol,
a yellow pigment was extracted which had absorption maxima at 440 nm and 325 nm and bright blue fluorescence (λmax 415 nm). A screening pigment (ommochrome) with maximum at 525 nm was extracted by acid methanol, and was probably related
to the group of ommines. The eyes of the lake population had 1.8–2.7 times less of this pigment than the eyes of the sea population.
The sea population is more resistant to photo-induced accumulation of thiobarbituric acid-reactive substances in eye tissues.
This resistance may be due to the higher ommochrome content.
Accepted: 8 December 1998 相似文献
84.
P. O. Zanen R. T. Cardé 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1999,184(1):21-35
By attaching a reflective strip to the thorax, we documented with video recordings in a wind tunnel the spatial orientation
of male gypsy moths, Lymantria dispar, as they flew along a plume of sex pheromone. In wind speeds of 61, 122, and 183 cm s−1, moths flew very similar tracks along a pheromone plume. Moths aimed their thrust closer to upwind in increasing wind speeds
using a roll maneuver. As a result, the orientation of their visual flow field, represented by the slip angle (the angular
distance between the direction of flight and the longitudinal body axis), remained relatively constant. We propose that directional
control during self-steered zigzagging is achieved by rolling, thereby maintaining a set slip angle. Following a roll at the
apex of a turn that aligns the moth with its preferred slip angle, a moth banks toward a cross wind leg. By banking moths
may maintain a stable image flow at oblique angles to their longitudinal body axis.
Accepted: 16 July 1998 相似文献
85.
A. Schmidt J. Engelage H.-J. Bischof 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1999,185(1):69-79
Responses of neurons of the optic tectum, the prominent, highly laminated mesencephalic station of the tectofugal visual
pathway in birds, to computer-generated and other visual stimuli were examined in zebra finches. Our study shows that the
contralateral retina projects to the tectum in topographic order. The representation of the visual field is tilted against
the horizon by 22°. The representation of the contralateral hemifield extends to the ipsilateral side by 15°. Most neurons
have receptive fields with excitatory centres of different shapes and inhibitory surround. A new type of neuronal receptive
field is described which has an excitatory centre and a surround which is movement sensitive and preferably excited by very
small spots. The first type of neurons is mostly located in upper tectal layers, the latter only in deeper layers. Excitatory
centre sizes increase with depth, and there is a tendency of smaller receptive fields in the foveal region. The representation
of the frontal visual field does not show specializations which could be expected if it were used for fixation of grain during
pecking. Our results are in accordance with previous behavioural experiments.
Accepted: 30 April 1999 相似文献
86.
异色瓢虫视觉系统中5-HT阳性神经元的分布 总被引:1,自引:0,他引:1
本文运用树脂石蜡(Colophony-Paraffin,CP;专利号:ZL98125709.7)组织包埋切片技术,结合免疫组织化学链酶菌抗生物素蛋白一过氧化物酶(Streptavidin-Peroxidase,SP)双染法,对异色瓢虫视觉系统中5-羟色胺(5-HT)能神经元的分布进行了初步研究。结果显示,异色瓢虫视觉系统的结构及5-HT免疫反应系统相对比较特殊。5-HT阳性神经元胞体数目较少,染色显著,并聚集成群。根据胞体定位、细胞形态及轴突走向,可大体分为5群,其中包括1群呈弱反应的光感细胞。5-HT阳性膨大纤维支配所有的视神经纤维网,并呈柱状或分层排列模式。结果表明5-HT作为经典的神经递质在昆虫的视觉信息处理过程中可能发挥重要的调节作用,且主要以远距离的广域神经调节模式为主,并在特定区域和GABA有伴随现象。此外,昆虫视觉系统中5-HT的含量还可能与其明暗适应的生理调节方式具有相关性[动物学报51(5):912—918,2005]。 相似文献
87.
Group members present physical and physiological differences according to their age, sex or social status, which could generate
motivation differences among individuals during travel. In spite of these divergences of interest among individuals, the group
succeeds more often than not in making a collective decision about departure time and which direction to take. To reach a
consensus decision, animals should exchange information relating to characteristics of group movement through different communication
channels. The main purpose of this study is to understand the function of behaviour patterns displayed during movements of
white-faced capuchins (Cebus capucinus). We designed experiments in which we provoked collective movements involving a binary choice. During experiments, a video
camera recorded the behaviour of each capuchin, which enabled us to determine which individuals displayed a behavioural pattern
during travel and how this behaviour influenced the other group members. We found that looking backwards seemed to permit
the recruitment of group mates during collective movement. This behaviour also seemed to allow the quantification of the number
of followers, since the emitter modified its locomotion speed according to this number. In this preliminary study, we showed
that visual behaviour was used to recruit and monitor group mates during collective movements and provided information on
mechanisms involved in maintaining cohesion and coordination among group members during travel. 相似文献
88.
In most species of small mammals, males are exposed to higher levels of risk than females because they compete for mates,
travel greater distances to find and procure mates, and/or defend a territory. This suggests that males and females might
have different responses to risky situations, such as the presence of a predator. We tested responses to a visual predator
cue (an owl silhouette) in male and female golden hamsters (Mesocricetus auratus). In a laboratory arena, there was no significant sex difference in the latency to enter the burrow or time spent in the
burrow immediately after exposure to the owl silhouette. Males, however, were less likely to be active during the 3-min period
following the animal’s exposure to the silhouette, indicating that male golden hamsters are more wary after exposure to an
aerial predator cue than females. Most studies of responses to predators or predator cues have not considered sex differences,
but our results show that males and females may have quite different responses to predator cues. Further work should be done
to characterize and quantify sex differences in response to predators or predator cues. 相似文献
89.
In this paper we present an improved model for line and edge detection in cortical area V1. This model is based on responses of simple and complex cells, and it is multi-scale with no free parameters. We illustrate the use of the multi-scale line/edge representation in different processes: visual reconstruction or brightness perception, automatic scale selection and object segregation. A two-level object categorization scenario is tested in which pre-categorization is based on coarse scales only and final categorization on coarse plus fine scales. We also present a multi-scale object and face recognition model. Processing schemes are discussed in the framework of a complete cortical architecture. The fact that brightness perception and object recognition may be based on the same symbolic image representation is an indication that the entire (visual) cortex is involved in consciousness. 相似文献
90.
Frederike Diana Hanke Guido Dehnhardt 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2009,195(7):643-650
In this study, we measured aerial visual acuity in harbor seals. As a first approach to the hypothesis that harbor seals can
obtain acute aerial visual acuity mediated by the interaction of the vertical slit-shaped pupil and the corneal flattening
although refractive measurements had revealed aerial myopia, visual acuity was tested as a function of luminance and pupil
dilation. We analyzed aerial visual acuity (minimal resolvable stripe width) in three harbor seals in a two-alternative-forced-choice
discrimination experiment. Our results further support the hypothesis that harbor seals possess an aerial visual acuity comparable
to the acuity in clear waters if the vertical slit pupil does not exceed the zone of corneal flattening in bright light. When
the pupil dilates with decreasing luminance, visual acuity decreases which might be due to deflected light from the stronger
curved peripheral cornea. 相似文献