The Optimal Foraging Theory

Food Selection in Beavers Based on Tree Species, Size, and Distance Laboratory 1, Ecology 201 Abstract. The theory of optimal foraging and its relation to central foraging was examined by using the beaver as a model. Beaver food choice was examined by noting the species of woody vegetation, status (chewed vs. not-chewed), distance from the water, and circumference of trees near a beaver pond in North Carolina. Beavers avoided certain species of trees and preferred trees that were close to the water. No preference for tree circumference was noted. These data suggest that beaver food c ...

Sugar Size and Diffusion Through a Mock-Cell Membrane

BIO 101L Instructor: L. Hauser Introduction Diffusion is the process in which a substance moves from an area of high concentration to an area of lower concentration.  It is important for membranes to be semi-permeable.  If membranes were universally permeable, they would not legitimately serve their purpose as membranes; certain substances need to be kept out of a cell, and others kept in.  If membranes were not at all permeable, there would be no interface between the cell and its environment – effectively starving the cell.  Membranes, being selectively permeable, allow in nutrien ...

Doyle Online Writing Lab

Ontogenetic Color Change and Mating Cues in Largus californicus (Hemiptera: Largidae) Carey Booth Box 123 Biology 102 2 February 1995 Lab instructor: Ned Knight Lab day: Friday Abstract Ontogenetic color change at sexual maturation can be useful in identifying an appropriate mate for some organisms. Largus californicus individuals undergo two ontogenetic color changes. First instars are bright red, second through fifth instars are shiny blue-black, and adults are black with orange markings. Adult male mating behavior suggested that the change in color from fifth instars to adults migh ...