Re: Punctuated Equilibrium Theory

Robin Hanson (
Fri, 25 Sep 1998 09:56:00 -0700

Curt Adams writes:
>>Granting that there is some variation in the rate at which environments
>>change, the question is: how much variation is that? ...
>I should have been more precise by saying that punctuated equilibrium
>predominates in *speciation*... the most important genes do
>roughly follow the exponential model, and the combined effects of the
>most important genes explains most of the variation between species. So
>even if small-effect genes are affected by environmental variation and
>don't follow Orr's model, they're not important for speciation, because
>the total effect of all minor genes combined is fairly small.

This thread started when Eliezer referred to punctuated equilibrium as support for his claim that future intelligence trajectories will mainly consist of big fast jumps between periods of little change. For this purpose, the relevant question is how concentrated in time was biological innovation. And given the framework you describe, to answer this we need to know both what fraction of biological innovation happens from speciation, and just how fast speciation innovation happens.

Even if "the combined effects of the most important genes explains most of the variation between species", it is not clear to me that this implies most biological innovation happens at speciation. And even for genes which do "follow the exponential model", the crucial question is "over how many orders of magnitude"?

Robin Hanson RWJF Health Policy Scholar, Sch. of Public Health 510-643-1884 140 Warren Hall, UC Berkeley, CA 94720-7360 FAX: 510-643-8614