From:
To: "Gordon Getty"
Cc: dhaig®oeb.harvard.edu, "Alan Rogers" <MI=Ila>, "Robert Frank"
Qhf3®comell.edu>, "Jeffrey Epstein" <jeevacation@gmail.com>
Subject: degree of r and age
Date: Wed, 27 Nov 2013 00:25:12 +0000
Importance: Normal
Dear Gordon
I very much like your slimmed down version of Hamilton/Fisher. Certainly
collapsing the main equation by N=I is obvious. Somewhat less so is the
matter of defining a benefit (B) i.e. an increase in reproductive success,
as a change in one' s reproductive value, which seems like a more permanent
character. In one sense yes: it has just gone up, but does the general,
let us say declining in older people rule, still not apply?-and is it
bumped throughout by the same benefit recently transferred ?
When I explicitly set out to build a theory of the family I knew the key
variables were degree of relatedness, sex and age—yet I never reached a
proper synthesis with the latter.
Here I would trust Alan Rogers more than myself; likewise, David Haig has
contributed the following, which also references Alan:
Ronald Lee has developed a model of intergenerational transfers that has some
interesting properties. The problem is that his model is implicitly one of
clonal
asexual reproduction (r = 1 for all transfers among individuals). I am not
sure
whether anyone has achieved a general model for transfers among relatives
which is
what Gordon is working at.
Lee, R. (2008) Sociality, selection, and survival: simulated evolution of
mortality
with intergenerational transfers and food sharing. Proceedings of the
National
Academy of Sciences, USA 105: 7124-7128.
Lee, R. D. (2003) Rethinking the evolutionary theory of aging: transfers, not
births, shape senescence in social species. Proceedings of the National
Academy of
Sciences, USA 100: 9637-9642.
and Alan Rogers has a commentary:
Rogers, A. R. (2003) Economics and the evolution of life histories.
Proceedings of
the National Academy of Sciences, USA 100: 9114-9115.
EFTA00977156
Note absence of parent-offspring conflict.
I will write you later re your very interesting piece on discounting. I am
copying David on all this
warmest best
bob
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