NREM/ZOOL 4464 – Ornithology Dr. Tim O’Connell Lecture 16 23 February 2011 Last time: •Life of Birds – origin of birds, and of flight. •Avian structure and feathers This time: •feather functions and molt Readings this week: Gill Ch. 4, 5 Feathers grow from follicles arranged in a specific pattern on the skin. These are the “tracts” or pterylae . Featherless areas on the skin are apteria . Feathers in particular tract colored differently from adjacent tracts can create bold patterns in plumage. Feather functions: •insulation (e.g., nestlings) •crypsis (e.g., owls, nestlings) •flight •species/gender recognition (e.g., sexually dimorphic species like Red-winged Blackbird) •special display (e.g., modified feathers of Club-winged Manakin, Marvelous Spatuletail) •waterproofing (e.g., Common Loon) •display (e.g., general display of health and vigor: pink color of Greater Flamingo) •Gathering food (e.g., rectal bristles) •Gathering water (e.g., modified belly feathers of sandgrouse) •Perch prop (e.g., woodpeckers) Bird topography