BIO220H1 Chapter Human-Induced evolution: 2018_BIO220_Readings_Human-induced

• School: UTSG
• Department: Biology
• Course: BIO220H1
• Professor: John Stinchcombe

Document Summary

Human-induced evolution caused by unnatural selection through harvest of wild animals. Harmed populations elephants, bighorn sheep, brown trout, and causes earlier maturation. The most desirable individuals have been harvested, leaving behind the less desirable individuals have been harvested, leaving behind the less desirable to reproduce and contribute genes to future generations. Therefore harvest of wild populations has tended to increase the frequency of less desirable phenotypes in wild populations. 3 types of selection: methodological, unconscious, and natural. Managers have focused on demographic parameters that affect population abundance and growth rate because their primary goal is sustainable yield in the short-term. Evidence is mounting that fish populations will not necessarily recover even if overfishing stops. Fishing may be such a powerful evolutionary force that we are running up a darwinian debt for future generations. Fisheries-induced evolution will tend to proceed along a trajectory that is counter to one that maintains trait combinations desirable to fisherman.