考古时期的温度趋势,是从复活的蛋白质中推断出预坎布里亚生命的趋势
Eric A Gaucher1, Sridhar Govindarajan, Omjoy K Ganesh
1Foundation for Applied Molecular Evolution, Gainesville, Florida 32601, USA.
Nature
|February 8, 2008
概括
地球上的古代生命经历了一种渐进的冷却趋势,在30亿年内减少了30°C. 这一发现基于复活的蛋白质和地质数据,揭示了生命的存在.
科学领域:
- 进化生物学 进化生物学
- 古气候学 古气候学
- 生物地质化学生物地质化学
背景情况:
- 微生物生命至少在地球上存在了35亿年,居住在不同的环境中.
- 以前的研究利用复活的蛋白质推断古代的环境条件,这表明早期的生命在炎热的条件下壮成长.
- 了解早期生命体验的温度波动对于重建地球环境历史至关重要.
研究的目的:
- 为了确定35亿至50亿年前有生命居住的环境的古气温趋势.
- 研究古代生命对环境温度变化的适应反应.
- 为了验证不同科学学科的发现.
主要方法:
- 复兴超过25个被遗传学分散的祖先延长因子.
- 对蛋白质热稳定性的分析,以推断古代环境温度.
- 与古海洋学数据的交叉验证,特别是氧同位素沉积.
主要成果:
- 从35亿至50亿年前的地球环境中推断出大约30°C的渐进式冷却趋势.
- 来自复活蛋白质的冷却趋势显示出对统计偏差和家族遗传不确定性的稳定性.
- 古代海洋的独立冷却趋势,来自氧同位素数据,证实了这些发现.
结论:
- 古代生命在数十亿年的时间里逐渐适应了地球冷却的环境.
- 来自自然科学和物理科学数据的融合加强了推断的古气温趋势.
- 进化史与环境温度波动密切相关.
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