The Virginia opossum, the only marsupial species native to North America, is a creature of remarkable biological distinction. Its reproductive cycle is arguably its most unique trait, involving a highly accelerated birth process followed by an extended period of external development. Understanding the young of this species requires exploring the specific terms used for them and the unusual journey they take from birth to independence.
The Specific Names for Opossum Babies
The most common term for a baby opossum is a joey, a name shared with the young of many other marsupials like kangaroos and wallabies. Alternative names, though less frequent, include pups or kits.
When referring to a group of opossums, the collective noun is a passel. The terms for the adults are also specific, with a male opossum being called a jack and a female referred to as a jill.
The Unique Marsupial Birth Journey
The reproductive cycle begins with a short gestation period, lasting only 12 to 14 days. This is one of the shortest pregnancy periods of any mammal, resulting in young that are still in a near-embryonic state at birth. At this stage, the tiny newborns are blind, hairless, and only about the size of a honeybee, weighing less than a tenth of an ounce.
Immediately after birth, the underdeveloped young must undertake an arduous and solitary journey to the mother’s pouch, or marsupium. Driven purely by instinct, the neonates crawl through the mother’s fur, using their relatively developed forelimbs. Upon successfully reaching the pouch, the surviving young will latch firmly onto one of the mother’s teats.
Development Inside and Outside the Pouch
Once secured inside the marsupium, the joey’s development continues for approximately two months. The teat swells inside the joey’s mouth, helping to keep it firmly attached for continuous nursing, acting as a temporary external umbilical cord. During this time, the young grow rapidly, and physical changes begin to occur, such as the opening of their eyes and the development of a fine coat of fur.
As they grow too large to comfortably fit inside the pouch, the joeys begin to venture out, often clinging tightly to their mother’s back for transportation. This transition marks the most recognizable phase of their early life, with a mother sometimes carrying over a dozen young as she forages. They remain with the mother until they are fully weaned, typically reaching independence around three to four months of age.