Food Level and Life History Characteristics in a Pholcid Spider (Holocnemus Pluchei)

Abstract

The effects of food level on development and adult body size were investigated for the pholcid spider Holocnemus pluchei. Increased food level significantly decreased development time from egg to adult. Spiders fed less food had longer stadia and were more likely to undergo an additional instar than spiders fed more food. Well-fed spiders of both sexes tended to be larger than poorly-fed spiders, though the relationship between food level and body size was less clearcut for females than for males. Adult female spiders that underwent an extra molt were significantly larger than those that did not. Because Holocnemus spiders often live in groups, and large spiders often steal food from smaller conspecifics, adult females reared under low food conditions that underwent an extra molt may have a competitive edge over their fast-growing, well-fed counterparts. © 1990, Hindawi Publishing Corporation. All rights reserved.