Department of Biology, East Carolina University, Greenville, NC 27858, USA.
Am Nat. 2010 Apr;175(4):436-46. doi: 10.1086/650727.
Linking specific ecological factors to the evolution of parental care pattern and mating system is a difficult task of key importance. We provide evidence from comparative analyses that an ecological factor (breeding pool size) is associated with the evolution of parental care across all frogs. We further show that the most intensive form of parental care (trophic egg feeding) evolved in concert with the use of small pools for tadpole deposition and that egg feeding was associated with the evolution of biparental care. Previous research on two Peruvian poison frogs (Ranitomeya imitator and Ranitomeya variabilis) revealed similar life histories, with the exception of breeding pool size. This key ecological difference led to divergence in parental care patterns and mating systems. We present ecological field experiments that demonstrate that biparental care is essential to tadpole survival in small (but not large) pools. Field observations demonstrate social monogamy in R. imitator, the species that uses small pools. Molecular analyses demonstrate genetic monogamy in R. imitator, the first example of genetic monogamy in an amphibian. In total, this evidence constitutes the most complete documentation to date that a single ecological factor drove the evolution of biparental care and genetic and social monogamy in an animal.
将特定的生态因素与亲代照顾模式和交配系统的进化联系起来是一项至关重要的艰巨任务。我们通过比较分析提供了证据，表明一个生态因素（繁殖池大小）与所有青蛙的亲代照顾进化有关。我们进一步表明，最强烈的亲代照顾形式（营养卵喂养）与在小池塘中沉积蝌蚪的行为同时进化，并且卵喂养与双亲照顾的进化有关。对两种秘鲁毒蛙（Ranitomeya imitator 和 Ranitomeya variabilis）的先前研究揭示了类似的生活史，除了繁殖池大小。这种关键的生态差异导致了亲代照顾模式和交配系统的分歧。我们提出了生态实地实验，证明在小（而非大）池塘中，双亲照顾对于蝌蚪的生存至关重要。实地观察表明，在使用小池塘的 R. imitator 中存在社会一夫一妻制。分子分析表明 R. imitator 存在遗传一夫一妻制，这是在两栖动物中首次发现遗传一夫一妻制的例子。总的来说，这些证据构成了迄今为止最完整的记录，证明了一个单一的生态因素驱动了双亲照顾以及遗传和社会一夫一妻制在动物中的进化。
