Summers K, Bermingham E, Weigt L, McCafferty S, Dahlstrom L
Smithsonian Tropical Research Institute, Balboa, Republic of Panama.
J Hered. 1997 Jan-Feb;88(1):8-13. doi: 10.1093/oxfordjournals.jhered.a023065.
Why some species exhibit remarkable variation among populations while closely related species are relatively uniform remains unclear. The strawberry dart-poison frog (Dendrobates pumillo) exhibits spectacular color and pattern polmorphism among populations in the Bocas del Toro archipelago of Panama. In contrast, two other sympatric species of dart-poison frog, Phyllobates lugubris and Minyobates sp., show little color or pattern variation among island populations. Here we demonstrate that the color and pattern variation among populations of D. pumilio is not matched by higher levels of mitochondrial DNA sequence divergence relative to P. lugubris or Minyobates sp. Thus, neutral divergence in allopatry is unlikely to have caused the geographical differences observed in D. pumilio. We suggest that strong sexual selection associated with female parental care in D. pumilio, which contrasts the male parental care of P. lugubris and Minyobates sp., may have driven divergence in coloration and pattern in D. pumilio.
为何有些物种在种群间表现出显著差异，而亲缘关系相近的物种却相对一致，这一点尚不清楚。草莓箭毒蛙（Dendrobates pumillo）在巴拿马博卡斯德尔托罗群岛的种群间展现出惊人的颜色和图案多态性。相比之下，另外两种同域分布的箭毒蛙物种，即悲哀叶毒蛙（Phyllobates lugubris）和小叶毒蛙属（Minyobates sp.），在岛屿种群间几乎没有颜色或图案变化。我们在此证明，相对于悲哀叶毒蛙或小叶毒蛙属，草莓箭毒蛙种群间的颜色和图案变化并未伴随着线粒体DNA序列更高水平的分歧。因此，异域分布中的中性分歧不太可能导致草莓箭毒蛙中观察到的地理差异。我们认为，与悲哀叶毒蛙和小叶毒蛙属由雄性亲代抚育不同，草莓箭毒蛙中与雌性亲代抚育相关的强烈性选择可能推动了其颜色和图案的分化。
