Adult male Eastern Fence Lizards (Sceloporus undulatus) possess blue and black ventral patches that function in sex recognition and intrasexual social signaling, but this ventral coloration is absent or greatly reduced in females and juvenile males. Adult males also exhibit a relatively uniform, reddish brown dorsal coloration, while females and juvenile males are cryptically colored, with two ...

Animal coloration is strikingly diverse in nature. Within-species color variation can arise through local adaptation for camouflage, sexual dimorphism and conspicuous sexual signals, which often have conflicting effects on survival. Here, we tested whether color variation between two island populations of Aegean wall lizards (Podarcis erhardii) is due to sexual dimorphism and differential survi...

Gregariousness ought to be disadvantageous for palatable organisms that live exposed and are relatively immobile and small in comparison to potential predators. Therefore, the idea that unpalatability generally evolves before egg clustering/larval gregariousness in butterflies was tested. Aposematic coloration in the larva was used as the criterion of unpalatability (it is argued that Batesian ...

Cryptic prey coloration typically bears a resemblance to the habitat the prey uses. It has been suggested that coloration which visually matches a random sample of the background maximizes background matching. We studied this previously untested hypothesis, as well as another, little studied principle of concealment, disruptive coloration, and whether it could, acting in addition to background ...

Female Petrosaurus mearnsi develop orange throat coloration when gravid. This coloration was induced in the nonbreeding season (late fall) by exogenous progesterone delivered by subcutaneous implantation in Silastic capsules or intramuscular injection. Color change was first apparent after five days of administration. The time course of brightening was similar for the two methods. Color change ...

Despite the importance of cryptic and conspicuous coloration in pelagic ecosystems, few researchers have investigated the optimal reflectance spectra for either trait. In this study, the underwater radiance distribution in tropical oceanic water was modelled using measured inherent optical properties and radiative transfer calculations. The modelled light field was then used to predict the refl...

Sexual selection theory predicts that females should choose males that signal viability and quality. However, few studies have found fitness benefits among females mating with highly ornamented males. Here, we use Arctic charr (Salvelinus alpinus), a teleost fish with no parental care, to investigate whether females could gain fitness benefits by mating with highly ornamented and large-sized ma...

siahe-e-samarghandi is one of the most important cultivars of grapevine (vitis vinifera) in fars province. some problems of this cultivar are its sparse clusters with small berries and berries that are in different stages of growth. foliar application of urea, zinc sulfate, boric acid 4, 3 and 1gl-1, respectively as well as sodium molybdate at the concentrations of 0, 0.5, 1 and 1.5 gl-1 were a...

Internal organs of ectotherms have melanin-containing cells that confer different degrees of coloration to them. Previous experimental studies analyzed their developmental origin, role in immunity, and hormonal regulation. For example, melanin increases with ultraviolet radiation (UV) and temperature in frogs and fish. However, little is known about how environmental variables influence the amo...