Song: Part 2

1. Song: Part 2

2. Is song learning in birds a new concept?

3. Is song learning in birds a new concept? “One has to consider that a young bird of any species, which neither hears an adult of its own kind nor has another young around itself never will attain its natural song completely but will sing rather poorly” – Pernau, early 1700s

4. Bullfinches taught to sing German folk songs “

5. “I am convinced (though it may seem paradoxical), that the inhabitants of London distinguish more accurately, and know more on this head, than all the other parts of the island taken together” - Daines Barrington, early 1800s; analogy explaining the importance of social context in song learning

6. “Sweetness of voice and melody of song are qualities, which in birds are partly natural, partly acquired” – Comte de Buffon, mid-1700s

7. But why the variation? What is the advantage to learning a dialect?

9. Tall eucalypt forest Dry rainforest Open eucalypt forest Rainforest Wet eucalypt forest

12. Same pattern in great tits

15. Habitat related song divergence between urban and forest birds Higher frequency songs in cities Differences in responses of urban and forest birds to playback; suggests population differentiation

16. And again, same pattern in great tits

17. Or…. Perhaps the advantage comes from matching songs to the singer’s social environment • Better communication with rivals, use neighbors as social tutors • Males should be able to fine-tune songs even after settling on a learned song when young

18. Second year matched neighbor song First year

19. Evolution of bird song: Ultimate explanations

20. What would Darwin ask?

21. Is there a fitness advantage to song? • May convey information on species membership • Territory defense • Mate attraction

24. John Krebs 1980s Wytham Woods near Oxford

27. No song

28. 2 3 1

29. Mate choice?

31. Experimental Evidence Observational Evidence • Captive mate choice trials • Experimental manipulation of male song • Song playback preference experiments • Males with “high-quality” sire their own offspring • Females seek extra-pair fertilizations from males with “high-quality” songs • Higher RS and survivorship in males with “high-quality” songs

32. Song Context Matters: Female zebra finches prefer the songs taken from males singing directly to females rather than those of males singing in the absence of a female