Sex-Correlated Coloration in Chiton tuberculatus

Growth and Duration of Life of Chiton Tuberculatus.

Formation in Chrysochromulina Chiton

The normal form of the species has been compared with a deviant form and the processes of scale production in both more fully studied. The deviation is shown to be genetically based, possibly a mutation, of which the main structural expression is loss of capacity to develop the normal outer layer of material on each scale. The large scales also lack rims, a flange on the back giving a spurious ...

Predation-associated differences in sex linkage of wild guppy coloration.

Evolutionary theory predicts that the sex linkage of sexually selected traits can influence the direction and rate of evolutionary change, and also itself be subject to selection. Theory abounds on how sex-specific selection, mate choice, or other phenomena should favor different types of sex-linked inheritance, yet evidence in nature remains limited. Here, we use hormone assays in Trinidadian ...

The Analysis of Neuromuscular Mechanisms in Chiton

1. The degree of curvature of the body and of the girdle of a Chiton is determined by the activity of antagonistic muscle groups. At a certain, early stage in the strychninization of a Chiton the reciprocal inhibition involved in the natural use of these muscle groups is reversed, such that extensor muscles, rather than, as normally, flexor muscles, contract as the result of stimulation. This c...

The Role of Wing Coloration in Sex Recognition and Competitor Recognition in Rubyspot Damselflies (Hetaerina spp.)

The decision rules that animals use for distinguishing between conspecifics of different age and sex classes are relevant for understanding how closely related species interact in sympatry. In rubyspot damselflies (Hetaerina spp.), the red wing coloration of mature males is hypothesized to be a key trait for sex recognition and competitor recognition within species and the proximate trigger for...