Flexibility in the timing of parturition: the key to viviparity in lizards?

分娩时间的灵活性：蜥蜴胎生的关键？

• 批准号: ARC : DP0210791
• 负责人: A/Prof Roy Swain
• 金额: $ 9.6万
• 依托单位: Antarctic Climate and Ecosystems CRC, University of Tasmania
• 依托单位国家: 澳大利亚
• 项目类别: Discovery Projects
• 财政年份: 2002
• 资助国家: 澳大利亚
• 起止时间: 2002-01-01 至 2005-12-31
• 项目状态: 已结题
• 来源: https://researchdata.edu.au/flexibility-timing-parturition-viviparity-lizards/74915
• 关键词: Flexibility; timing; parturition; key; viviparity

Flexibility in the timing of parturition: the key to viviparity in lizards? Embryos of viviparous lizards usually gain adequate nutrients from yolk. Why then has placentotrophy evolved in some species, and what new opportunities has it opened up? The answer may lie in the advantages gained from flexibility in the timing of birth, made possible by supplementary transfer of storage lipids to embryos during gestation. We argue that this provides a pivotal opportunity for evolutionary divergence: some alpine species exploit flexible parturition; other species replace optional placentotrophy with obligate transfer. Our unique experimental approach, using two well-researched clades of viviparous skinks, will result in new testable hypotheses about the evolution of viviparity.

分娩时间的灵活性：蜥蜴胎生的关键？胎生蜥蜴的胚胎通常从蛋黄中获得足够的营养。那么，为什么某些物种会进化出胎盘营养型，它又带来了哪些新机遇呢？答案可能在于出生时间的灵活性所带来的优势，这可以通过在妊娠期间将储存脂质补充转移到胚胎来实现。我们认为，这为进化分歧提供了一个关键的机会：一些高山物种利用灵活的分娩方式；其他物种用专性转移取代了选择性胎盘营养。我们独特的实验方法，使用两个经过充分研究的胎生石龙子分支，将产生关于胎生进化的新的可检验的假设。