Behavioral Basis of Shared Paternity in the Striped-backed Wren

一个成功的动物（在进化的意义上）是一个， 行为，以便最大限度地代表其基因， 后人 因此，动物可以成功地 或者像通常发生的那样，通过养育自己的后代，或者 帮助养育与自己密切相关的后代， 发生在大多数“合作育种者。“例如， 在成对鸟的巢中的帮手经常帮助 他们的父母养育的后代是他们自己的同胞兄弟姐妹。 在委内瑞拉的纹背鹪鹩中， 在一个特定的社会群体中， 他们成熟了。 由于死亡率很高， 死亡的女性被与之无关的移民女性所取代 这个团体，帮助者经常帮助抚养他们的另一半， 兄妹 因此，一个占主导地位的女性和她的死亡， 被移民取代对男性来说是一件大事， helper. 他母亲的死（1）突然减少了遗传 他所享受的好处是帮助抚养统治者的后代 一对（因为女性不再是他的母亲）和（2）创建 一个通过交配进行非乱伦繁殖的机会 新的主导女性。 最近的行为研究 显示男性助手经常追求并试图追求 占主导地位的女性与他们无关， 主导地位的女性被主导地位的男性所统治。 DNA指纹图谱，a 分子技术用于分配亲子关系，已经表明，15%， 所有来自有男性帮手的团体的青少年， 与占统治地位的雌性的后代是男性助手和占统治地位的 女性 剩下的85%是占优势的一对的后代。 派珀博士的研究项目将更详细地比较 男性助手的行为是占主导地位的女性的儿子， 那些与她无关的。具体来说，他将检查 男性助手倾向于与占主导地位的女性交往， 占主导地位的男性对男性助手的待遇，以及 由男性助手提供的父母照顾。 这项研究将增加 我们对帮助行为和避免乱伦的理解 合作繁殖动物，更一般地说， 帮助行为的进化。

A successful animal (in the evolutionary sense) is one that behaves so as to maximize the representation of its genes in future generations. Therefore, an animal can be successful either by raising its own offspring, as usually occurs, or by helping to raise offspring that are closely related to itself, as occurs in most "cooperative breeders." For example, adult helpers at the nests of mated pairs of birds are often helping their parents raise offspring that are their own full siblings. In the stripe-backed wren of Venezuela, males and females raised in a given social group become helpers in the same group when they mature. Since the mortality rate is high and dominant females that die are replaced by immigrant females unrelated to the group, helpers often help raise juveniles that are their half siblings. Thus, the death of a dominant female and her replacement by an immigrant is a significant event for a male helper. His mother's death (1) suddenly decreases the genetic benefit he enjoys by helping to raise offspring of the dominant pair (since the female is no longer his mother) and (2) creates an opportunity for him to reproduce non-incestuously by mating with the new dominant female. Recent behavioral research revealed that male helpers routinely pursue and attempt to court dominant females unrelated to them and are only kept from mating with dominant females by dominant males. DNA fingerprinting, a molecular technique used to assign parentage, has shown that 15% of all juveniles from groups that contain male helpers unrelated to the dominant female are offspring of male helpers and dominant females. The remaining 85% are offspring of the dominant pair. Dr. Piper's research project will compare in more detail the behavior of male helpers that are sons of the dominant female and those that are unrelated to her. Specifically, he will examine the tendency of male helpers to associate with dominant females, the treatment of male helpers by dominant males, and the amount of parental care given by male helpers. This study will increase our understanding of helping behavior and incest avoidance in cooperatively breeding animals and, more generally, will give insight into the evolution of helping behavior.