BISC 102 Lecture Notes - Lecture 10: Species Problem, Asexual Reproduction, Genetic Drift

• School: Simon Fraser University
• Department: Biological Sciences
• Course: BISC 102
• Professor: Ivona Mladenovic

Document Summary

Microevolution: changes within a species equals changes in allele frequencies. Macroevolution: evolution on a large scale. Disruptive selection: favours variants at both extremes of distribution. Groups of actually or potentially interbreeding natural populations that are reproductively isolated from other groups. The (cid:271)iologi(cid:272)al spe(cid:272)ies (cid:272)o(cid:374)(cid:272)ept (cid:272)a(cid:374)(cid:859)t (cid:271)e applied to the follo(cid:449)i(cid:374)g spe(cid:272)ies: known only from fossil records, asexually reproducing, do not overlap geographically. How do we know if fossil forms were interbreeding. What if (cid:449)e do(cid:374)(cid:859)t o(cid:271)ser(cid:448)e (cid:373)ati(cid:374)g: morphological similarity can be used to indicate interbreeding, but it may be subjective. If morphologically similar organisms do not interbreed, consider genetic relatedness: but threshold genetic difference is not defined. Morphological species concept: based on similarity of resource of appearance, can be subjective, used by linnaeus. Ecological species concept: based on similarity of resource and habitat use, can be difficult to define exact niche.