Territorial response of a male great tit to a speaker broadcasting an intruder song

Killarney National Park, field site for songbird cognition studies

Common frog spawn in County Cork, Ireland

Bullfrog in Missouri

Deer skeleton, McPherson Pond

Mating pair of Hypsiboas rufitelus at La Selva, Costa Rica

Moon over McPherson

Metamorphosis

Grasshopper collection site in Germany

Red eyed treefrogs, Agallychnis callidryas, in Costa Rica

Moth, Stillwater, OK

Calling male Hyla chrysoscelis

Leptodactylus pentadactylus, the smokey jungle frog

Toad explosion, McPherson Pond

Female Dendropsophus ebraccatus in Costa Rica

Mating cricket frogs, Stillwater, OK

Cruziohyla calcarifer at La Selva, Costa Rica

Heavy bullfrog, McPherson Pond

A blue tit nest, from studies of bird cognition and breeding in County Cork, Ireland

An amazing glass frog in Costa Rica

Studying cognition in wild songbirds in the famous Wytham Woods

Cantarrana (singing frog) swamp, La Selva, Costa Rica