A guide to nestling development and aging in altricial passerines

"We present nestling data on seven species of altricial passerines: Dusky Flycatcher (Empidonax oberhoseri), Carolina Wren (Thryothorus ludovicianus), Wrentit (Chamea fasciata), Sprague's Pipit (Anthus spragueii), Song Sparrow (Melospiza melodia), Chestnut-collared Longspur (Calcarius ornatus), and American Goldfinch (Cardeulis tristis)"--P. 4.