1. 12.1

2. 12.2

3. 12.3 (a) Classical conditioning (b) Instrumental conditioning Static features (CS) Movement or other salient feature (US) Recognition (UR) Stimulus absence (S D ) Aversive internal state is reduced (S R ) Following response (R i ) Following response Aversive internal state Following response strengthened

4. 12.4 Lesioned birds (a) (b)

5. 12.5

6. 12.6 Isolation

7. 12.7

8. 12.8

9. 12.9

10. 12.10 Dog-reared monkeys Hobbyhorse-reared monkeys Fonsie Sandy Sue Ping Tasha Ron Catfish Shawn Marcy Jarvis Poppy KC Proximity Agonistic Affiliative

11. 12.11

12. 12.12

13. 12.13 0 5 10 0 5 0 5 Frequency (kHz) 00.51.01.52.0 Time (s) (a) (b) (c)

14. 12.14 Swamp SparrowSong Sparrow Normal song Isolate song: Hearing intact Isolate song: Deafened before singing

15. 12.15 Hatching (summer) Nesting period Juvenile period (fall and winter) (spring) First breeding season Adult life Sensorimotor learning phase Crystallized or adult song Plastic song Subsong No song production Acquisition of an auditory memory Flexible sensitive period Initial social interactions Exposure to song Sensory learning phase

16. 12.16 0.5 s 5 kHz Morin Berkeley Sunset Beach San Francisco Bay Area

17. 12.17 Song (input) Vocal behavior (output) Basilar membrane Cochlear nucleus DLM NO Posterior telencephalon Anterior telencephalon HVCRA Nucleus of the Hypoglossal nerve Syringeal muscles LMAN N. XII N. VIII Area X

18. Size of brain nuclei involved in song learning Quality of song repertoire (a proxy for cognitive abilities related to foraging efficiency) Female sexual preference Early nutrition Early stress Feeding efficiency during the plastic song phase Endocannabinoid brain levels Sexual selection contributing to the evolution of a large telencephalon and higher cognition in songbirds 12.18