BIOL 302 Lecture Notes - Lecture 18: Ruffe, Epigenetics, Life History Theory

• School: Queen's University
• Department: Biology
• Course: BIOL 302
• Professor: Paul Martin

Document Summary

Bio302 lec 17 (october 23, 2017) life histories. Fisheries as a selective pressure on life histories. Agi(cid:374)g: (cid:862)the gradual (cid:272)ha(cid:374)ges i(cid:374) the stru(cid:272)ture of a (cid:373)ature orga(cid:374)is(cid:373) that o(cid:272)(cid:272)u (cid:373)or(cid:374)all(cid:455) o(cid:374)(cid:448)er ti(cid:373)e a(cid:374)d i(cid:374)(cid:272)rease the pro(cid:271)a(cid:271)ilit(cid:455) of death. (cid:863) Irreversible damage to cells: accumulation of late-acting, deleterious alleles (hard for slecetion to eliminate, genes beneficial for early life are sometimes detrimental later in life (i. e antagonistic pleiotropic effects) (eg. testosterone) Why do different organisms age at different rates: variation through nature, associated with environmental selective pressures, e(cid:454)ter(cid:374)al fa(cid:272)tors (cid:894)predatio(cid:374) (cid:895, there is no sense in repair if you get eaten so instead you invest in reproduction. What"s u(cid:374)derl(cid:455)i(cid:374)g it : all three of these things are contributing. It fits w what we see in nature: when we look across species, ex. Island tortoises(188-255), green land shark (400 yrs old), ocean quahog (507yrs: plants: bristlecone pine (5067 yrs old, ba(cid:272)teria: reprodu(cid:272)i(cid:374)g (cid:271)(cid:455) (cid:271)i(cid:374)ar(cid:455) fissio(cid:374) so(cid:373)e (cid:374)e(cid:448)er reall(cid:455) die.