Dating the Time of Origin of Major Clades: Molecular Clocks and the Fossil Record
Dating the Time of Origin of Major Clades: Molecular Clocks and the Fossil Record
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DOI：
10.1146/annurev.earth.30.091201.140057
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发表时间：
2002-05
影响因子：
14.9
通讯作者：
A. Smith;K. Peterson
中科院分区：
文献类型：
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作者：
A. Smith;K. Peterson
■摘要分子和古生物学数据提供了独立的方法来估计生物群在地质历史中何时进化，但这两种方法都不能被认为是简单的。从基因序列数据中准确估计起源时间的唯一最根本的障碍是分子进化速率的变化，无论是在时间上还是在谱系之间。尽管已经提出了各种技术来规避这个问题，但没有一种明确地允许将时间和速率的分量分开。此外，建立精确的校准点、正确地确定根数和精确估计分支长度的问题仍然是艰巨的。相反，古生物学的年代只能确定最晚的可能的分歧时间，因此需要概率方法来确定起源日期的下限。考虑到理性偏差的现实置信区间才刚刚出现。尽管分子和古生物学...
▪ Abstract Molecular and paleontological data provide independent means of estimating when groups of organisms evolved in the geological past, but neither approach can be considered straightforward. The single most fundamental obstacle to developing an accurate estimate of times of origination from gene sequence data is variation in rates of molecular evolution, both through time and among lineages. Although various techniques have been proposed to circumvent this problem, none unambiguously allow the components of time and rate to be separated. Furthermore, problems of establishing accurate calibration points, correctly rooted phylogenies, and accurate estimates of branch length remain formidable. Conversely, paleontological dates fix only the latest possible time of divergence, and so probabilistic methods are required to set a lower boundary on origination dates. Realistic confidence intervals that take preservational biases into account are only just becoming available. Although molecular and paleonto...