Polydactylism in a siamang.
D000818:Animals; D000831:Animals, Newborn; D000836:Animals, Zoo; D001724:Birth Weight; D005385:Fingers / Q000002:abnormalities*; D015186:Hominidae; D008297:Male; D010012:Osteogenesis; D014034:Toes / Q000002:abnormalities*