PT  - JOURNAL ARTICLE
AU  - Graham E. Budd
AU  - Richard P. Mann
TI  - History is written by the victors: the effect of the push of the past on the fossil record
AID  - 10.1101/194753
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 194753
4099  - http://biorxiv.org/content/early/2017/10/13/194753.short
4100  - http://biorxiv.org/content/early/2017/10/13/194753.full
AB  - Phylogenies may be modelled using “birth-death” models for speciation and extinction, but even when a homogeneous rate of diversification is used, survivorship biases can generate remarkable rate heterogeneities through time. One such bias has been termed the “push of the past”, by which the length of time a clade has survived is conditioned on the rate of diversification that happened to pertain at its origin. This creates the illusion of a secular rate slow-down through time that is, rather, a reversion to the mean. Here we model the controls on the push of the past, and the effect it has on clade origination times, and show that it largely depends on underlying extinction rates. Crown group origins tend to become later and more dispersed as the size of the push of the past increases. An extra effect increasing early rates in lineages is also seen in large clades. The push of the past is an important but relatively neglected bias that affects many aspects of diversification patterns, such as diversification spikes after mass extinctions and at the origins of clades; it also influences rates of fossilisation, changes in rates of phenotypic evolution and even molecular clocks.