Sexual selection occurs through male competition and female choice. It leads to the evolution of extreme traits in males that give them an advantage in attracting mates but may reduce survival. Sexual dimorphism arises when males and females of a species differ in traits, often with males developing more ornamented characteristics. Runaway selection can cause traits to evolve that do not improve quality but instead fulfill female preferences, like long bright tails in some species. Sexual selection drives evolution and speciation.

1. Sexual SelectionBy: Angela, Sarah, and Saima

2. Sexual selection goes both waysMakes organisms go to extremesSelection types: Male competition and Female ChoiceRunaway selectionSexual dimorphismEvolution and changesSexual Selection

3. Better survival chances for offspringWeaker genes are eliminated – not chosen to reproduceProduce offspringPurpose of Sexual Selection

4. Intrasexual selectionMale goes for extreme competition for mateSecondary characteristics are used for mate competitionCharacteristics that are not mandatory for breedingMale CompetitionElephant mating

5. Intersexual selectionPick mates to increase the survival of its offspringCompare the secondary characteristic in maleFemales pick their mates based on their looks, situation, and behaviour.Female ChoiceTragopanSatyar Video

6. The differences in male and female of the same speciesMales often have more deleterious charactersCharacteristics that reduce survival chancesSexual Dimorphism

7. A.k.a. arbitrary sexual selectionDeveloped by Sir Ronald Aylmer FisherFemale’s choice cause deleterious characteristic development in malesChange in male characteristics doesn’t equal to higher qualityRunaway Selection

8. Anagenesis occurs due to Female choicesChanges that occur within a species overtimeSensory ExploitationHarmful characteristics evolve in males to attract female – fulfill reproductive needsi.e. Long, bright colour tailsEvolution

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