BIO220H1 Lecture Notes - Lecture 14: Gene Expression, Natural Selection, Anisogamy
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BIO220H1 Full Course Notes
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Document Summary
About 90% of genes are shared between males and females: all autosomes. Gene expression of shared genes in most tissues differs between the sexes: most evident in the gonads (morphological differences as well, also in most other tissues, e. g. , liver, brain. In fruit flies: 50-90% of all genes in the fly genome are expressed differently in the sexes. The evolution of sexual differences (dimorphisms) lecture goals: Most examples come from birds: males have large, colourful feathers and vary greatly between species females look much more drab and difficult to differentiate between species. Greater sage-grouse gather on a lek to attract females. Males have inflatable sacks and do a dance to attract females armaments. E. g. , antlers are much larger on males (use for fighting with other males) compared to females. E. g. , horns on beetles females prefer males with longer armaments peacock displays. Males have large, exaggerated tails and females are drab and uncolourful.
