EEB386H1 Study Guide - Final Guide: Bird Vocalization, Courtship Display, Vocal Learning
17 Apr 2017
School
Department
Course
Professor
Document Summary
4 components of annual cycle: breeding, moult, wintering, migration. Success in one stage depends on previous stage. Energy storage/transfers important: ex: need to have pre-migratory fattening before migration. Ultimate control of annual cycles: seasonality + effects on food supply. Proximate control of annual cycles: endogenous rhythms linked to daylength. Birds = seasonal breeders (don"t breed all year round) Birds = long day breeders (mate, incubate, rear young in spring + summer when daylength is increasing) Have rapid development times: = can complete breeding cycle during warm period. Mammals (sheep + cows) = short-day breeders: mate in fall, gestation occurs in winter, still rear young in spring + summer (peak food abundance) Acts as neuro-hormone on brain to control aggressive behaviour (chasing + fighting) In male white-crowned sparrow + other temperate breeding birds, testosterone surge when males set up territories + chase intruders. High testosterone levels interfere w/ parental care so need lower levels in breeding season.
