Wolff J O
Department of Fisheries and Wildlife, Oregon State University, Corvallis 97331-3803.
Nature. 1992 Oct 1;359(6394):409-10. doi: 10.1038/359409a0.
Juvenile dispersal is sex-biased in many mammals and birds: one sex often disperses more often or farther than the other. Two hypotheses are generally presented for sex-biased dispersal. The first holds that juvenile dispersal reduces reproductive and/or resource competition between parents and same-sexed offspring. If so, presence of a parent on the natal home range should both promote dispersal of same-sex offspring and suppress reproduction of those that remain. The second is that juvenile dispersal reduces matings between parents and offspring, thus decreasing the likelihood of inbreeding depression. If so, presence of a parent should favour dispersal and reproductive suppression of offspring of the opposite sex. Here I present evidence that juvenile dispersal in white-footed mice, Peromyscus leucopus, is due to inbreeding avoidance. When population density was high, experimental removal of one parent delayed dispersal of opposite-sexed offspring and only the presence of the parents of opposite sex suppressed juvenile reproduction.
在许多哺乳动物和鸟类中，幼体扩散存在性别偏差：一种性别的个体通常比另一种性别的个体扩散得更频繁或更远。关于性别偏差扩散，通常提出两种假说。第一种假说认为，幼体扩散减少了父母与同性后代之间的生殖和/或资源竞争。如果是这样，出生地范围内父母的存在应该既促进同性后代的扩散，又抑制留下的后代的繁殖。第二种假说是，幼体扩散减少了父母与后代之间的交配，从而降低了近亲繁殖衰退的可能性。如果是这样，父母的存在应该有利于异性后代的扩散和生殖抑制。在此，我提供证据表明，白足鼠（Peromyscus leucopus）的幼体扩散是为了避免近亲繁殖。当种群密度较高时，实验性移除一方父母会延迟异性后代的扩散，只有异性父母的存在会抑制幼体繁殖。
