Effects of climatic conditions on sex ratios in nests of broad‐snouted caiman
Effects of climatic conditions on sex ratios in nests of broad‐snouted caiman
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气候条件对宽吻凯门鳄巢穴性别比例的影响
DOI：
10.1111/jzo.12140
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发表时间：
2014
影响因子：
2
通讯作者：
C. Piña
中科院分区：
文献类型：
--
作者：
M. Simoncini;F. B. Cruz;A. Larriera;C. Piña
凯门鳄的性别决定取决于温度，并且可能容易受到环境温度波动的影响，从而容易受到全球气候变化现象的影响。考虑到 Ca 温度升高的潜在后果。为了研究宽吻鳄的后代，我们研究了气候条件对凯门鳄在野生巢中产生的性别比例的影响，特别是气候变量如何影响巢穴温度和产生的雌性百分比。我们还探讨了假设巢穴温度升高 0.5 和 1.0°C 对凯门鳄种群的潜在影响。由于巢穴平均温度在 27.1 至 33.9°C 之间变化，在野外巢穴中产下的雌性比例因繁殖季节而异。然而，七个季节之后，性别比例偏向雌性，并且只有在极端事件（强烈的厄尔尼诺南方涛动事件、拉尼娜现象）期间，野生雌性的比例才会减少。在全球变暖的假设情景中，我们预测单性雌性巢穴会减少，同时包含两性或单性雄性巢穴的情况会变得更加频繁。如果巢穴温度长时间升至 34.5°C 以上，整个窝可能会丢失。然而，雌性可能会改变它们的筑巢时间和行为，以选择温度适宜的筑巢环境。
Caiman latirostris has temperature-dependent sex determination and is potentially susceptible to environmental temperature fluctuations and, thus, to the global climate change phenomena. Considering the potential consequences of increasing temperatures for Ca. latirostris offspring, we examined the effects of climatic conditions on sex ratios produced by caimans in wild nests and in particular how climate variables affect nest temperature and the percentage of females produced. We also explored the potential consequences of a hypothetic 0.5 and 1.0°C increase in nest temperature on caiman populations. The proportion of females produced from nests in the wild varied among reproductive seasons, as mean nest temperatures varied between 27.1 and 33.9°C. However, after seven seasons the sex ratio biased toward females, and only during extreme events (strong El Nino Southern Oscillation event, La Nina) was there a reduction in the percentage of females produced in the wild. In the hypothetic scenarios of global warming, we predict a decrease of unisexual female nests, with nests containing both sexes or unisexual male nests becoming more frequent. Entire clutches might be lost if nest temperatures rise above 34.5°C for extended periods. However, it is possible that females modify their nesting timing and behavior to select thermally suitable nest environments.
DOI：
10.1073/pnas.91.16.7487
发表时间：
1994-08-02
影响因子：
11.1
作者：
JANZEN, FJ
通讯作者：
JANZEN, FJ