Animals foraging for patchily distributed resources may optimize their foraging decisions concerning the patches they encounter, provided that they base these decisions on reliable information about the profitability of the habitat as a whole. Females of the parasitoid Lysiphlebus testaceipes...

This paper uses the mode of production of the hunter-gatherers as a background to explain basic economic concepts, in particular the meaning of the labour theory of value and it's relationship to optimization of resources. A proof of the marginal value theorem is presented. A new term is...

Larval Macrostemum carolina caddisflies construct silken catchnets within protective retreats, often on submerged trees and branches (i.e., snags). In the Savannah River, M. carolina larvae construct three distinct retreats that differ in the configuration of the water entrance hole: (1) at the...

The "asset-protection principle" created by Clark is based on a dynamic programming model and states that individuals should (1) become more averse to predation risk as they accumulate fitness assets but (2) generally be more willing to accept predation risk later in the foraging season. To test...

The optimal residence time of a forager exploiting a resource patch in the absence of competitors has been much studied since the development of the marginal value theorem. However, several foragers are frequently observed exploiting the same patch simultaneously, and patch residence time has...

The study on biodiversity of aquatic insects was carried out covering the area of Kuala Keniam to Kuala Perkai River, National Park, Pahang, Malaysia. The macro invertebrate community was found in the different types of micro-habitat and various flowing speed levels in good quality of water of...

The Trivers and Willard model (TWM) predicts that for sexually dimorphic polygynous mammals, mothers able to provide a high level of care should bias offspring sex ratio in favor of sons. Contradictory results of empirical studies, however, suggest that selective pressures for adaptive offspring...