Relaxed phylogenetics and dating with confidence drummond
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A good thing too, you might think, and it is undoubtedly true that Darwin's clear and flowing narrative style helped ensure the popularity of his writings.
On a phylogeny this means that neighbouring branches have more similar rates than distant branches, a property termed “autocorrelation”.
The idea that rates of sequence evolution can be “inherited” in this way played an important role in the history and development of evolutionary theory [ 7, 12], and it is well known that viruses, bacteria, and animals evolve at hugely different rates, but the assumption has never been comprehensively tested.
Unfortunately, this approach underestimates the amount of evolutionary change because it does not account for the fact that each site may change more than once during evolutionary history.Such questions can be answered only if independent information about rates or divergence times is found.Often paleontology or biogeography can provide a date for one or more points in a phylogeny, which are then used to “calibrate” the timescale for the rest of the phylogeny [ 3, 4].Modern research in evolutionary biology can make for less easy reading.Much of it concerns the development of an expanding arsenal of mathematical and statistical techniques, necessary to do battle with the relentless onslaught of gene and genome sequences.