On the effect of temperature-dependent sex determination on sex ratio and survivorship in crocodilians
On the effect of temperature-dependent sex determination on sex ratio and survivorship in crocodilians
复制标题
温度依赖性性别决定对鳄鱼性别比和存活率的影响
DOI：
10.1098/rspb.1993.0059
复制
发表时间：
1993
期刊：
影响因子：
--
通讯作者：
J. Murray
中科院分区：
文献类型：
--
作者：
D. Woodward;J. Murray
短吻鳄和鳄鱼的性别比例强烈偏向雌性，通常高达10比1。偏斜的性别比例（即1：1以外的比例）通常在表现出环境性别决定的物种中发现。在鳄鱼中，卵孵化的温度是决定性别的环境因素。如果温度很低，大约30 °C，孵化的小海龟都是雌性。温度较高，约34 °C，孵化所有男性。任何一个特定的雌性个体成功繁殖自己的概率很低，因为卵、孵化的幼鸟和未成熟的幼鸟的死亡率很高。然而，鳄鱼有很大的生存能力：没有（分类）鳄鱼或鳄鱼的物种已经灭绝，尽管广泛的狩猎和栖息地的丧失。我们开发了一个非线性的年龄结构模型的人口动态的短吻鳄和鳄鱼的关键生活史数据的基础上。从我们的建模，我们得出结论：（一）性别比例是受生存的考虑;和（二）温度依赖性的性别决定鳄鱼是一个妥协，提供有性生殖的优势，同时保持不平衡的性别比例。
The sex ratio of alligators and crocodiles is strongly biased towards females, often as high as 10 females to 1 male. Skewed sex ratios (that is, ratios other than 1:1) are commonly found in species exhibiting environmental sex determination. In crocodilians the temperature of egg incubation is the environmental factor determining sex. If the temperature is cool, around 30 °C, the hatchlings are all female. Warmer temperatures, around 34 °C, hatch all males. The probability that any particular individual female will successfully reproduce herself is low due to high mortalities of eggs, hatchlings and immatures. However, the crocodilia have great survivorship: no (classified) species of alligator or crocodile has become extinct despite extensive hunting and loss of habitat. We develop a nonlinear age-structured model for the population dynamics of alligators and crocodiles based on key life-history data. From our modelling we conclude that: (i) sex ratio is constrained by survivorship considerations; and (ii) temperature-dependent sex determination in crocodilians is a compromise providing the advantages of sexual reproduction while maintaining an unbalanced sex ratio.
乌克兰科学院地质研究所（乌克兰）
DOI：
--
发表时间：
--
期刊：
影响因子：
--
作者：
通讯作者：
--