>

> I suspect many people are upset at having to multiply for IQ

>

> i.e. Iq = G*E

>

> and find that something seems to be missing. Of course, it is

> missing.

> Can simple multiplication be the best model for something so

> complex

> when it does not suffice even for freshman physics which

> describes

> point masses, acceleration along straight lines, massless springs

> etc

> of nonvolitional dead bodies?

I know of no quantitative genetic model that would say

IQ=G*E. The standard model is additive:

P=A+D+E+G*E+I etc

where P is the phenotype (IQ in this case) , A is the

Additive genetic effect, and D the non-additive effect (ie

dominance); E is the effect of the environment. G*E is not

a multiplicative function, but a statistical inteaction, as

are gene x gene interactions (I).

These terms are all pretty meaningless when applied to

individuals, but are easily interpreted as VARIANCES (when

poplation diffrences in these terms can be determined).

If you have suitable data (difficult to get for humans and

IQ, but easy for plants and other phenotypes) you can get

estimates of all these terms and show that this additive

model of gene action is pretty good.

Why should IQ be any difefrent to any other character in

humans, animals or plants?

>

> I think they want a more complex mathematical model which is

> better at

> taking into account much of the evidence from real life. For

> example,

> they might want an equation that does something like "if the

> genetic

> disposition is low...etc etc."

This contingent type model will come out in G*E term of the

standard model.

----------------------

Mark Macnair

Professor of Evolutionary Genetics

Director of Postgraduate Studies

Hatherly Laboratories

Department of Biological Sciences

University of Exeter

Prince of Wales Rd

Exeter EX4 4PS

UK

Tel: 44 (0) 1392 263791

Fax: 44 (0) 1392 263700