Estimating metazoan divergence times with a molecular clock
نویسندگان
چکیده
منابع مشابه
Estimating metazoan divergence times with a molecular clock.
Accurately dating when the first bilaterally symmetrical animals arose is crucial to our understanding of early animal evolution. The earliest unequivocally bilaterian fossils are approximately 555 million years old. In contrast, molecular-clock analyses calibrated by using the fossil record of vertebrates estimate that vertebrates split from dipterans (Drosophila) approximately 900 million yea...
متن کاملEstimating divergence times in phylogenetic trees without a molecular clock.
were nonstationary at first positions for the ingroup at P = 0.01 using the chi-square test in PAUP*. The chi-square test in PAUP∗ appears to do a good job of identifying the worst offenders and although crude, is effective for a large data set when analyzing individual genes. We certainly anticipate that as more refined tests of stationarity are implemented (e.g., Foster, 2004), discrimination...
متن کاملEstimating divergence times in large molecular phylogenies.
Molecular dating of species divergences has become an important means to add a temporal dimension to the Tree of Life. Increasingly larger datasets encompassing greater taxonomic diversity are becoming available to generate molecular timetrees by using sophisticated methods that model rate variation among lineages. However, the practical application of these methods is challenging because of th...
متن کاملEstimating divergence times in the presence of an overdispersed molecular clock.
Molecular loci that fail relative-rate tests are said to be "overdispersed." Traditional molecular-clock approaches to estimating divergence times do not take this into account. In this study, a method was developed to estimate divergence times using loci that may be overdispersed. The approach was to replace the traditional Poisson process assumption with a more general stationary process assu...
متن کاملComparing a Menagerie of Models for Estimating Molecular Divergence Times
Estimation of molecular evolutionary divergence times requires models of rate change. These vary with regard to the assumption of what quantity is penalized. The possibilities considered are the rate of evolution, the log of the rate of evolution and the inverse of the rate of evolution. These models also vary with regard to how time affects the expected variance of rate change. Here the altern...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2004
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.0401670101