• 引证/输出
  引证/输出

  复制引证文献

  APA（第6版）

  

  芝加哥（著者-日期，第15版）

  

  Harvard（第18版）

  

  MLA（第7版）

  

  Turabian（第6版）

  

  输出引证文献

  输出到RefWorks   输出到EndNote / 参考管理（Reference Manager）   输出到EasyBib   删除

  请注意： 这些引证文献都以参考咨询的标準為基础。但是，处理格式的规则，在应用程序、感兴趣或研究的领域之间会大相径庭。应当考虑到负责復审的出版商、上课的教师、机构或者组织的具体要求或者优先选择。
• 打印
• 电子邮件
  电子邮件

  所有的字段都要。

  电邮地址字段是一定要有的。请输入收件人的电子邮件地址。

  输入的电邮地址格式不对。请重新输入收件人的电邮地址。

  最多可将资料送给五个收件人。

  输入收件人的电子邮件地址： 最多能用逗号（,）将五个地址分开

  名字的字段是一定要有的。请输入您的名字。

  输入你的名字： 主题的字段是一定要有的。请输入主题。 主题:

  电子邮件讯息的字段是一定要有的。请输入讯息。

  电子邮件： 我想你可能会对这资料感兴趣，资料位于 http://www.worldcat.org/oclc/486560045 题名： Proximate and Functional Causes of Polyphenism in an Anuran Tadpole 出版商： ISBN/ISSN: 0269-8463 OCLC:486560045

  
  

  输入的ReCaptcha词条不对。要设法和显示在窗口中的那两个字一样，也可试用音频版。

  删除
• 共享
• 永久链接
  永久链接

  复制URL以便和网页链接：

• 撰写评论
• 评估这资料：
• • 1
  • 2
  • 3
  • 4
  • 5

Proximate and Functional Causes of Polyphenism in an Anuran Tadpole

著者：	D W Pfennig
版本/格式：	文章 : 英语
刊登在：	Functional Ecology, 1992, vol. 6, no. 2, p. 167-174
数据库：	JSTOR
提要：	Few systems have been explored in sufficient detail to link the proximate causes of polyphenism to the ecological factors that favour discontinuous, environmentally induced variation. I examined the developmental and physiological bases underlying polyphenism in southern spadefoot toad tadpoles (Scaphiopus multiplicatus). Scaphiopus often occurs as two discrete trophic morphs: carnivores and omnivores. Carnivores develop from omnivores if the latter are fed macroscopic prey (anostracan shrimp and tadpoles). I found that tadpoles can change to the alternative morphology if their diet was switched. Static allometric analyses indicated that morph determination results from acceleration (or retardation) of certain anatomical features. I hypothesized that morph determination is triggered by the presence of a potent accelerator of amphibian development occurring in the carnivore's prey: thyroid hormone (or its constituents). Omnivores exposed exogenously to thyroxine assumed the carnivore morphology within days. This endocrine response enables tadpoles to develop into the morph with the greater fitness since the rapidly developing carnivores are favoured in highly ephemeral ponds, which contain more shrimp. Carnivores also are more efficient predators of shrimp. This study thus links the underlying physiological causes of a polyphenism to the ecological factors that likely favour the occurrence of alternative morphs. More generally, this study illustrates how an endocrine signal may allow an individual to assess and continuously adapt to a changing environment.  再读一些...
评估：	(尚未评估) 0 附有评论 - 争取成为第一个。
在出版物中使用下列的字词搜索其他文章：