Sexual selection theory
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Darwin's sexual selection theory argues that males compete for females through mechanisms like intra-sexual competition between males or inter-sexual choice by females, resulting in the development of secondary sexual characteristics in males like antlers, songs, or colorful feathers. Examples include the vocal cords in frogs, antlers in deer, songs of male birds, and the colorful feathers of peacocks. However, the theory was criticized for not fully explaining sexual dimorphism and for assuming behaviors like promiscuity that could prevent sexual selection from occurring.
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Sexual selection theory
- 2. DARWIN SEXUAL SELECTION THEORY Sexual selection “depends not on the struggle for existence, but on the struggle between males for possession of females
- 3. SALIENT FEATURE OF SEXUAL SELECTION THEORY Mechanisms of sexual selection Intra- selection Inter-selection Competition & fight B/w males For Female Secondary sexual characters Mostly Develop in males Female lack Male Competition Direct Indirect
- 4. EXAMPLE OF SEXUAL SELECTION VOCAL CORDS IN FROG ANTLERS IN DEERS SONG PRODUCED BY MALE BIRD COLOURED FEATHERS OF PEACOCK
- 5. DRAWBACKS IN DARWIN SEXUAL SELECTION THEORY Does not explain sexual dimorphism. Natural selection would actually select against sexual selection. Promiscuous intercourse will prevent or check the action of sexual selection Female choice driving evolution was almost universally mocked and dismissed