Intraspecific competition in the speckled wood butterfly Pararge aegeria: Effect of rearing density and gender on larval life history

摘要: In insects, the outcome of intraspecific competition for food during development depends primarily upon larval density and sex, but effects will also depend on particular trait under consideration species study. Experimental manipulations densities a Madeiran population speckled wood butterfly Pararge aegeria confirmed that affected growth. As increased P. adults were smaller periods longer. Sexes responded differently to rearing density. Females more adversely by high than males, resulting in females having masses at pupation. Survivorship was significantly higher larvae reared low densities. No effect adult sex ratios observed. Intraspecific stage would appear carry cost males. This may confer double disadvantage since are dependent their derived resources reproduction as they have little opportunity accumulate additional adults. suggests shortages could affect fecundity directly. Males, however, be able compensate small size feeding and/or altering mate location tactics.