ON CONIFEROPHAGOUS SPECIES OF CHORISTONEURA (LEPIDOPTERA: TORTRICIDAE) IN NORTH AMERICA: IV. SEXUAL ISOLATION BETWEEN THREE SPECIES

Abstract

Tests of sexual isolation indicate that, in the absence of temporal and spatial isolation, the strict mating behavior of the females and the high sexual aggressiveness of the males of Choristoneura fumiferana (Clem.) would obstruct any inward flow of genes from either C. occidentalis Free, or C. biennis Free. Under these same conditions, however, the two latter species may receive genes from C. fumiferana, since, in tests, their females mated indiscriminately and their males were less aggressive than those of C. fumiferana.