Saturday, 11 June 2011

YouTube: Ethology Lessons 1

James Lee on reproductive strategies in vertebrates.

Researchers conducted an experiment with guppies. They moved a group of guppies from a lake with low predation to one with high predation. They noticed, after just 10 years, that the new group grew to smaller adult sizes, reproduced earlier, more frequently, had more offspring, and a faster growth rate than the original group. 

They concluded that individuals in a stable environment can afford to wait before reproducing whereas individuals in environments with high mortalities tend to reproduce faster, as a biological response to predation.

This is the same for humans too. Humans livings in environments with high infant mortalities experience greater birth rates, and as resources go up, birth rates go down. Also, people moving from low resource environments to high resource ones tend towards obesity. Their body has adapted to fewer resources, but since people in general are programmed to consume as much food as is freely available, people from low resource areas are especially at risk of obesity. It is important to understand the biological causes of behaviour.


No comments:

Post a Comment