Mouse deer are the smallest members of the animal family that includes pigs, hippos, camels, deer, antelopes, sheep and goats. Adults are 45 to 55 centimetres long (18 to 22 inches) and can live for about 12 years.It is found in Brunei, Cambodia, China, Indonesia, Laos, Malaysia, Myanmar, Singapore, and Thailand. Its natural habitat is subtropical or tropical moist lowland forests.