BIO220H1 Lecture Notes - Lecture 6: Sexual Selection, Natural Selection

• School: UTSG
• Department: Biology
• Course: BIO220H1
• Professor: James Thomson

Document Summary

Natural selection acts against fish that are bigger than x. One benefit of mendelian traits is that we can determine the genotype from the phenotype. We cant look at any of these indivduals and determine their genotype because these are continuous traits. This selection is called truncated selection because we lose some proportion of the population. If these individuals die, the evolutionary response in the population would be natural selection on the larger individuals and we want to look at the mean size of the fish. Its 8-10 = -2 and nt +2 because the mean size is decresing. Whe(cid:374) de(cid:374)sity is lo(cid:449), (cid:271)ody size i(cid:374)(cid:272)reases (cid:271)e(cid:272)ause theres (cid:374)o (cid:272)o(cid:373)petitio(cid:374) for food. Whe(cid:374) a(cid:271)u(cid:374)da(cid:374)(cid:272)e (cid:272)rashes, (cid:271)ody size (cid:272)rashes a(cid:374)d does(cid:374)"t re(cid:272)o(cid:448)er. During high temperature, it increases the growth of the fish. In 1977, for 6 year old fish the large fish were favoured. In 1982 for 8 year old fish small fish were favoured.