Immunological factors inPeromyscus speciation

摘要: Reciprocal interspecific F1 hybrids of deermice (Peromyscus maniculatus) and oldfield mice (P. polionotus) differ significantly substantially in fetal placental, as well adult, size weight. Hybrid mortality is associated with large conceptus size. Skin grafts were exchanged between within the two species to ascertain whether any relationship exists mean graft retention time body fetuses adults. P. maniculatus skin grafted polionotus rejected earlier than reciprocal xenograft. All combinations intraspecific grafts. Pre-immunization female con- trans-specific paternal spleen cell antigens reduced fetal, neonatal, ten-day compared controls. Size, weight, fertility, rejection data several theoretical models. The consistent hypothesis that immunological disparity could produce marked variations hybrids. Multiple minor histocompatibility factors can account for placental Peromyscus Physiological reproductive isolation may result from differences closely allied species.