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511.
The coexistence of both aposematic and cryptic morphs as different anti-predator strategies within a species seems to be an
unusual phenomenon in nature. The strawberry poison frog, Oophaga pumilio, shows an astonishing colour diversity among populations in western Panama. In this study we selected a red and a green colour
morph from two Panamanian islands (Isla Solarte and Isla Colón) for behavioural observations and measurements of conspicuousness.
We found that red frogs were more visible to both conspecific frogs and potential predators than green frogs. Interestingly
the difference in conspicuousness was most pronounced at the substrate that males used as principal calling places. Red males
were more active and spent more time foraging than green males, which spent more time hidden. The association between conspicuousness
of colouration and behaviour results in a more aposematic and a more cryptic anti-predator strategy. This is the first study
which links differences in conspicuousness between animals on their natural backgrounds to differences in foraging as well
as anti-predator behaviour and discusses the results in light of previous findings of toxicity analyses and potential costs
and benefits of aposematism. To this end, our study adds a novel perspective for explaining extreme colour diversity between
populations within an initially aposematic species. 相似文献
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Microphthalmia: a new recessive mutation in the Norway rat 总被引:2,自引:0,他引:2
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E Luchter-Wasylewska J Dulińska W S Ostrowski V P Torchilin V S Trubetskoy 《Biotechnology and applied biochemistry》1991,13(1):36-47
Human prostatic acid phosphatase (PAP) (EC 3.1.3.2) was covalently linked to chondroitin sulfate A from whale cartilage. In order to bind the protein amino groups with the preactivated carboxyl groups of chondroitin sulfate, 1-ethyl-3-(3'-dimethylaminepropyl)carbodiimide and N-hydroxysulfosuccinimide were used as coupling agents. The product was soluble and enzymatically active. The activity was on average 25% higher than that of the free enzyme. The product was heterogeneous in respect to charge and Mr (50-1500) kDa, as determined by chromatography on Sephacryl S 300 and polyacrylamide gel electrophoresis. The resulting polymers contained covalently bound chondroitin sulfate, as shown by the biotin-avidin test. The modified enzyme is more resistant against various denaturing agents, e.g., urea, ethanol, and heat. Thus covalent modification of PAP by cross-linking to chondroitin sulfate could be the preferred method for stabilization of its biological activity. 相似文献
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