Comments on: Plagues & molecules?

By: Fly

Fly — Wed, 30 Jan 2008 09:46:51 +0000

"Underlying this health/ mortality differential are significant social class differences in average IQ."

Consider this toy model for an average community:

Over 90% were low class who were often starving before winter ended. They would have been malnourished and sickly.
The upper class would never starve and would regularly eat meat. They would be healthy and strong.
High status men would regularly father bastards in the lower classes. Also upper class families would expand and displace the lower classes.

Alleles would regularly flow from the upper class to the lower class. Strong selection pressure in the lower class would eliminate the low fitness alleles. In this model the lower class would average more high fitness alleles than the upper class. However, due to differences in nutrition and health, the upper class phenotype would be significantly better.

In this toy model, selection for intelligence might occur within the upper class but the between class genetic differences should have little affect on long term community genetics.

In a society with abundant, nutritious food and high social mobility, class differences may be largely genetic. It is not clear to me that this was commonly true in the Middle Ages.

By: pconroy

pconroy — Wed, 30 Jan 2008 08:07:19 +0000

David B,

I thought the same when I read it!

They are surely comparing Apples and Oranges – as the London area was densely populated and had many urban slums – ideal habitats for rats – whereas Viborg and Odense are little more than towns…

By: pconroy

pconroy — Wed, 30 Jan 2008 08:02:37 +0000

BGC,

I totally agree!

In the Great Irish Famine of the mid-1840′s in Ireland, the poorest 15-20% of the population died – they were largely servants, laborers and so on, they mostly subsisted on the potato and lived in the West of the country. The emigrants to the US and elsewhere were from the small farmer class. The large farmers not only survived but prospered in tis era. I grew up in the East of the country – where the land is very fertile and traditionally grain crops are grown and not too many potatoes – and know of some very prosperous families, whose fortune was made during the famine, when they greatly increased their land holdings, by offering a pittance to the destitute for their small farms.

By: David B

David B — Wed, 30 Jan 2008 02:11:03 +0000

Excuse my naivety, but wouldn’t it be more useful to compare Black Death cemeteries in England with other cemeteries in England? Preferably in the same geographical area, and both urban, or both rural.

By: BGC

BGC — Tue, 29 Jan 2008 22:46:27 +0000

As a general rule there are always social class differentials in mortality, with people getting healthier and longer lived as they get wealthier.

Underlying this health/ mortality differential are significant social class differences in average IQ.

Gottfredson has made this the basis of a theory of the relatively) recent evolution of intelligence.

When you combine social class IQ differences with social class health and mortality differences (and differences in reproductive success), this could well have constituted a major selection basis for the increase of intelligence in human populations which have inhabited complex agricultural societies.

http://www.udel.edu/educ/gottfredson/reprints/2004fundamentalcause.pdf