1. Leks Hotspot Female preference –Male aggregations –Hotshots Kin selection The lek paradox

2. Swedish for mating arena No male parental care No resource on territory Males aggregate and display at traditional sites Leks

3. Leks -> antelope Leks occur when females are not defensible grouse & ptarmigan

4. Males defend tiny territories on a lek Bat video

5. Male mating success on leks Sage grouse video

6. Lekking and frugivory in birds Lek Exploded lek Territory

7. New World lekking birds ManakinsBell birds Cock-of-the-rock

8. Hypotheses for male clustering Hotspot –males aggregate to maximize female encounter rate Female preference –Females prefer to select mates in aggregations –Females prefer central male –Females prefer attractive male (hotshot) and other males aggregate around him Kin selection –Males aggregate around relatives

9. The hotspot model

10. Leks of leks suggest hotspots Hermit hummingbird Ochre-bellied flycatcher Red-capped manakin Blue-crowned manakin

11. Sage grouse leks and hotspots Lek location Female nest density

12. Possible reasons for female preference to mate at a lek Reduce predation –No evidence in sage grouse More efficient comparison of males –Reduce mate searching costs –But, assuming male quality is normally distributed, advantage of choosing best male is greatest in small, not large, leks –Can copy choice of others Number of males Std dev units Best-of-n expectation

13. Mate choice copying in sage grouse Green = observed, orange = predicted w/out copying

14. Mate choice copying simulations

15. Do leks recruit more females/male in kob? No!

16. Do leks recruit more females/male in ruff? Sometimes!

17. Are black grouse hotshots? Yearly shift suggests male attractiveness, not position, is important

18. Related manakins on leks Shorey et al. 2000 Nature 408:352-353 Also in peacock, black grouse, satin bowerbirds, wild turkeys

19. The lek paradox In lekking species, males only pass sperm. Therefore, only indirect benefits are possible. If males differ in genetic quality, then females should always prefer the male of highest quality. Over time, such intense selection will deplete and possibly eliminate genetic variation. What then do females gain by choosing?

20. Solution to the lek paradox Genetic variation must persist for ornamental traits and genetic quality Ornament expression depends on condition. –Only males in good condition are able to fully express ornament –Condition is likely influenced by many genes. Consequently, deleterious mutations constantly replenish genetic variation.

21. Sage grouse condition and display