BIOL 304 Lecture Notes - Lecture 25: Irish Elk, Sexual Selection, Mortality Rate
Document Summary
Irish elk antlers are example, huge, disadvantage to male but selected upon. Natural selection acts on growth cycles/2n & n. Sexual selection acts on gamete fusion up to reproduction, intra (within sexes) and inter (between sexes) Mortality rate in humans: striking dimorphism women live much longer, 12-25, highest mortality rate in males. Strongly related to how many females & males are in a population. 1:1 relationship is usual. (sexual selection, fitness advantage for males is higher if more females than males, as males can mate unlimitedly) Fing fisher can only interact with female if he brings fish, also seen in other species (pisaura spiders with insects, katydids with pouch). In many population, females prefer orange spots on males (may be loosely related to carotenoids in food). Also seen in american house finches and red-legged partridge. Males fo not look red if no carotenoids are consumed.
