plosone-phylo
pone.0053967.g002
Characteristic species size pattern and cladogenetic diffusion model.(A) The characteristic distribution of species body sizes, observed in most major animal groups. Macroevolutionary tradeoffs between short-term selective advantages and long-term extinction risks, constrained by a minimum viable size , produce the distribution’s long right-tail. (B) Schematic illustrating the cladogenetic diffusion model of species body-size evolution: a descendant species’ mass is related to its ancestor’s size M by a random multiplicative factor . Species become extinct with a probability that grows slowly with M.
pone.0053967.g002
Characteristic species size pattern and cladogenetic diffusion model.(A) The characteristic distribution of species body sizes, observed in most major animal groups. Macroevolutionary tradeoffs between short-term selective advantages and long-term extinction risks, constrained by a minimum viable size , produce the distribution’s long right-tail. (B) Schematic illustrating the cladogenetic diffusion model of species body-size evolution: a descendant species’ mass is related to its ancestor’s size M by a random multiplicative factor . Species become extinct with a probability that grows slowly with M.