Horth Lisa, Travis Joseph
Department of Biological Science, Florida State University, Tallahassee, FL 32306-4340, USA.
Proc Biol Sci. 2002 Nov 7;269(1506):2239-47. doi: 10.1098/rspb.2002.2143.
Altering the genetic composition of a population can alter several aspects of its numerical dynamics. Whether natural populations routinely contain the genetic variation capable of affecting the stability of those dynamics is less clear. Here we report a study of experimental populations of mosquitofish (Gambusia holbrooki), designed to examine this issue. The experiment examined the numerical effects of varying the initial relative frequency of a rare male genotype. A higher relative frequency of the rare, melanic genotype produced higher mortality rates in melanic males, higher mortality rates in females, higher juvenile abundance, and fewer fluctuations in the numbers of females across time. This work demonstrates that a natural population can harbour genetic variants in a single gender that are capable of inducing qualitative differences in the numerical dynamics of the opposite gender, through the effects of negative frequency-dependent selection.
改变种群的基因组成会改变其数量动态的多个方面。自然种群是否通常包含能够影响这些动态稳定性的基因变异尚不清楚。在此，我们报告一项针对食蚊鱼（盖氏食蚊鱼）实验种群的研究，旨在探讨这一问题。该实验研究了改变一种罕见雄性基因型的初始相对频率所产生的数量影响。罕见的黑色基因型的相对频率较高时，会导致黑色雄性的死亡率更高、雌性的死亡率更高、幼鱼数量更多，并且雌性数量随时间的波动更小。这项研究表明，自然种群中单一性别的基因变异能够通过负频率依赖选择的作用，在相反性别的数量动态中引发质的差异。
