Bill (name and common meanings) Bill Overview of the English name Bill and the principal senses of the word “bill”, including personal name, proposed law, invoice, banknote, and bird's beak.
Bird (Aves): characteristics, evolution, behavior, and human relationships Bird Comprehensive overview of birds (Aves): anatomy, adaptations for flight, evolutionary origins, behavior and life cycle, human uses and conservation, plus notable distinctions and f…
Cloaca: single posterior chamber for excretion and reproduction in vertebrates Cloaca Cloaca: a single posterior chamber in many vertebrates that expels urine and feces and supports reproductive functions, found in birds, reptiles and monotremes, and contrasted with…
