Phenotypic variation in adult morphology and pupal colour within and amongfamilies of the speckled wood butterfly Pararge aegeria

1. Larvae from eggs of fifteen wild-caught speckled wood females were reare d individually under common conditions (LD 18:6 h and 17 degrees C) in the laboratory. 2. Pupal colour (green or brown) and the following adult morphological vari ables that are known or assumed to be related to behavioural variation (the rmoregulation, flight, crypsis) were studied: size, relative thorax mass, a rea of yellow patches on the dorsal forewing, size of submarginal eyespots on the dorsal hindwing, colour of the dorsal thorax, dorsal basal wing, and dorsal distal wing. 3. The results of the breeding experiment indicate significant differences in adult morphological traits among families, sexes, and pupal colour types . 4. All adult morphological variables (except spot size and thorax colourati on) differed significantly among families, suggesting genetic variation und erlying the phenotypic variation. Heritabilities for these features were in termediate (0.38) to high (> 1). 5. Apart from known aspects (e.g. size), novel aspects of the sexual dimorp hism were found: females had paler thoraxes than males, which relates to hi gher abundance of fur on the thorax and hence to thermoregulatory differenc es. 6. Green pupae produced larger individuals with a larger relative thorax ma ss than brown pupae. Green pupae produced adults with a paler basal wing co lour in females, but not in males. These relationships are novel and sugges t a trade-off between juvenile and adult investment.