On Thu, 24 Apr 2014 16:44:09 Jason White wrote:
For intelligence it's not so clear, while there are obvious biological factors that cause low intelligence (EG fetal alcohol syndrome) it's not clear that there is anything significant we can do to improve things. However the link between intelligence (as measured by IQ tests) and parenting/environment is clear.
I've heard it claimed that the average scores on IQ tests have increased over time, in certain countries, well beyond anything that could be explained biologically; but I haven't read any literature to confirm or dispute this finding.
In recent times most people who live to the age of 35 have children so evolution is going to work slowly. The increase in measured IQ over the last 100 years is obviously not from evolution. http://en.wikipedia.org/wiki/Human_height#History_of_human_height Better food etc makes a significant difference. One obvious example of this is average height which varies a lot by country and class. It seems most likely that a difference in diet which causes a group of people to be on average 22cm taller than another group in the same country also has an affect on IQ. http://www.theguardian.com/uk/2000/aug/13/education.educationnews1 Changes in schooling can also have a significant affect. The above article describes the benefits of home schooling which among other things removes class and gender differences in test results. I don't think we'll get to the ideal situation of having ~80% of kids home- schooled any time soon. But even in the education system there is a lot of room for improvement.
I think the idea for human enhancement of intelligence, though, would be to increase IQ biologically if appropriate means (genetic selection of children, gene therapy, drugs or whatever) were avilable.
The human brain is very complex. DNA is more complex than most people realise too and changes to it don't always show up in the next generation. For example consider the way that methyl groups can get added to DNA to modify it's operation, these things can change during someone's life and events when a boy is ~12 or before a girl is born can modify the way the genes work for their children. DNA changes are risky. However breeding for intelligence is happening. There are apparently sperm banks that only accept donations from guys who have a high IQ. That's not going to change the average IQ quickly because so few women use such services. -- My Main Blog http://etbe.coker.com.au/ My Documents Blog http://doc.coker.com.au/