鹿子宫肋的发病率增加表明它们面临灭绝的风险
Raimon Cuxart-Erruz1, Tom J M Van Dooren1,2, Alexandra A E van der Geer1
1Naturalis Biodiversity Center, Division Vertebrate Evolution, Development and Ecology, Darwinweg 2, Leiden 2333 CR, The Netherlands.
概括
已灭绝的巨鹿和同系的Père David鹿中宫肋骨的高发病率表明,近亲繁殖增加了灭绝的风险. 这一发现可能解释了在代晚期的大草食动物灭绝.
科学领域:
- 古生物学的古生物学
- 进化生物学 进化生物学
- 遗传学 是一个遗传学.
背景情况:
- 哺乳动物通常拥有七个椎,这是一个保存的特征.
- 像宫肋骨这样的偏差与先天性异常有关,并且在人类中被选择.
- 以前的研究表明,椎肋骨与已灭绝的大动物中不良状况之间存在联系.
研究的目的:
- 为了研究已经灭绝的巨鹿 (Megaloceros giganteus) 和现存的Père David鹿 (Elaphurus davidianus) 的宫肋发生率.
- 测试该假设,近亲繁殖和不利条件增加宫肋频率在人口下降.
- 评估宫肋频率作为灭绝风险的代理.
主要方法:
- 在爱尔兰巨鹿和Père David鹿的化石遗骸中检查了宫肋骨发生率.
- 结果与其他20种现存的鹿物种进行了比较.
- 在人口遗传学和进化压力的背景下分析数据.
主要成果:
- 在爱尔兰大鹿和大卫鹿中观察到异常高的宫肋发生率.
- 宫肋频率在这些同系种群中明显高于现存的外系鹿.
- 数据支持了将近亲繁殖和遗传漂移与增加的适应不良等位基因联系在一起的假设.
结论:
- 亲生繁殖和遗传漂移提高了危种群中不适应性等位基因的频率.
- 高椎肋骨发病率意味着一个脆弱的条件,可能有助于大草原动物灭绝.
- 宫肋频率可以作为一种有价值的标志物,表明同系品种的灭绝风险.
关键词:
埃拉弗鲁斯·达维迪亚努斯 (Elaphurus davidianus) 是一个古老的动物.晚期普莱斯托纪晚期的普莱斯托纪.这种巨大的巨 (Megaloceros giganteus).有先天性异常.亲生繁殖是一种繁殖方式.更多相关视频
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