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1.
A recent examination of color vision in the ringtail lemur produced evidence that these prosimians could make color discriminations consistent with a diagnosis of trichromatic color vision. However, it was unclear if this behavior reflected the presence of three classes of cone or whether lemurs might be able to utilize signals from rods in conjunction with those from only two classes of cone. To resolve that issue, spectral sensitivity functions were obtained from ringtail lemurs (Lemur catta) and brown lemurs (Eulemur fulvus) using a noninvasive electrophysiological procedure, electroretinographic flicker photometry. Results from experiments involving chromatic adaptation indicate that these lemurs routinely have only a single class of cone photopigment in the middle to long wavelengths (peak sensitivity of about 545 nm); they also have a short-wavelengthsensitive cone pigment with peak of about 437 nm. The earlier behavioral results are suggested to have resulted from the ability of lemurs to jointly utilize signals from rods and cones. The cone pigment complements of these lemurs differ distinctly from those seen among the anthropoids. © 1993 Wiley-Liss, Inc. 相似文献
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Response of female melon fly, Bactrocera cucurbitae, to host-associated visual and olfactory stimuli 总被引:3,自引:0,他引:3
Jaime C. Piñero Isabel Jácome Roger Vargas & Ronald J. Prokopy† 《Entomologia Experimentalis et Applicata》2006,121(3):261-269
In a series of studies conducted in Hawaii under seminatural conditions, we quantified the response of sexually mature, host‐seeking female melon flies, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae), to different types of visual and chemical host‐associated stimuli with the main aim of developing a monitoring device for females. Experiments were conducted using Tangletrap‐coated fruit mimics of either spherical (8 cm diameter) or cylindrical (4.3 cm diameter; 15 cm length) shapes coated with different artificial color pigments both at the ground level and at the tree‐canopy level so as to take into account the foraging behavior of adult melon flies. Females were particularly attracted to objects of spherical shape colored either yellow, white, or orange; these three pigments offered the highest reflectance values. Cucumber (Cucumis sativus L.) (Cucurbitaceae) odor was more attractive to females than odors of three other cultivated host fruit [zucchini, Cucurbita pepo L. var. medullosa Alef. (Cucurbitaceae); papaya, Carica papaya L. (Caricaceae); or tomato Solanum lycopersicum L. (Solanaceae)] or of ivy gourd [Coccinia grandis (L.) Voigt (Cucurbitaceae)], one of the major wild hosts of melon fly in Hawaii. A combination of both visual and olfactory stimuli was needed to elicit high levels of response compared to each stimulus offered alone. We discuss our results in relation to the potential implementation of improved female monitoring and/or attract‐and‐kill strategies for melon flies in Hawaii. 相似文献
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《Current biology : CB》2020,30(13):2433-2445.e3
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Gerald H. Jacobs 《International journal of primatology》2007,28(4):729-759
The visual worlds of most primates are rich with potential color signals, and many representatives of the order have evolved
the biological mechanisms that allow them to exploit these sources of information. Unlike the catarrhines, platyrrhines typically
have sex-linked polymorphic color vision that provides individuals with any of several distinct types of color vision, including
both trichromatic and dichromatic variants. In recent years, this polymorphism has been the target of an expanding range of
research efforts. As a result, researchers now reasonably understand the proximate biology underlying the polymorphisms, and
a number of ideas have emerged as to their evolution. Progress has also been made in illuminating how color vision capacities
may be related to the particular visual tasks that New World monkeys face. 相似文献
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Madeleine St Clair Yewers Devi Stuart‐Fox Claire Alice McLean 《Ecology and evolution》2019,9(1):295-306
Space use including territoriality and spatial arrangement within a population can reveal important information on the nature, dynamics, and evolutionary maintenance of alternative strategies in color polymorphic species. Despite the prevalence of color polymorphic species as model systems in evolutionary biology, the interaction between space use and genetic structuring of morphs within populations has rarely been examined. Here, we assess the spatial and genetic structure of male throat color morphs within a population of the tawny dragon lizard, Ctenophorus decresii. Male color morphs do not differ in morphology but differ in aggressive and antipredator behaviors as well as androgen levels. Despite these behavioral and endocrine differences, we find that color morphs do not differ in territory size, with their spatial arrangement being essentially random with respect to each other. There were no differences in genetic diversity or relatedness between morphs; however, there was significant, albeit weak, genetic differentiation between morphs, which was unrelated to geographic distance between individuals. Our results indicate potential weak barriers to gene flow between some morphs, potentially due to nonrandom pre‐ or postcopulatory mate choice or postzygotic genetic incompatibilities. However, space use, spatial structure, and nonrandom mating do not appear to be primary mechanisms maintaining color polymorphism in this system, highlighting the complexity and variation in alternative strategies associated with color polymorphism. 相似文献
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Phenylketonuria (PKU) is a widespread autosome recessive hereditary disease caused by a deficiency of the liver enzyme phenylalanine
hydroxylase, which results in distortion of metabolism of phenylalanine and accumulation of toxic metabolites. The knowledge
of molecular bases of PKU is of a high social importance as it enables phenotypic correction of the disease in the case of
its early diagnostics. This disease is known to be associated with mutations in the phenylalanine hydroxylase gene, the distribution
and mutation spectrum having pronounced ethnic and regional features. We studied the spectrum of mutations in the phenylalanine
hydroxylase gene in a group of patients with PKU from the Novosibirsk region to reveal 10 missense point mutations, 1 mutation
in the splice donor site, and 1 microdeletion. For these mutations, most widely distributed in the region, we used straightforward
detection methods basing on the restriction fragment length polymorphism (RFLP), artificial constructed restriction sites
(ACRS) PCR, and denaturing gradient gel electrophoresis (DGGE). 相似文献