Behavior Birds 41 Primates 39 Social behavior in animals 39 Ecology 35 Psychology 35 Dogs 28 Chimpanzees 27 Research 27 Evolution 25 Ants 21 Cognition in animals 20 Human-animal relationships 20 Animal communication 18 Cats 16 Conservation 16 Dolphins 16 Mammals 16 Apes 14 Insects 14 Animal behavior 11 Training 11 Psychology, Comparative 10 Effect of human beings on 9 Animal intelligence 8 Domestic animals 8 Habitat 8 Honeybee 8 Horses 8 Human behavior 8