Armadillos and possums are familiar sights across North America, often observed in backyards or along roadsides. Despite their common presence and distinct appearances, these creatures are frequently misunderstood. Their unique adaptations allow them to thrive in various environments, from woodlands to suburban areas. While both are part of the continent’s diverse wildlife, their biological relationships are not always clear.
The Direct Answer
Armadillos and possums are not closely related, despite sometimes sharing habitats. These animals belong to entirely different mammalian orders. While they may occasionally be mistaken for one another due to superficial resemblances or co-occurrence, their evolutionary paths diverged millions of years ago.
Why the Confusion
People often confuse armadillos and possums due to several shared characteristics. Both species are primarily nocturnal, and their geographical ranges overlap significantly, particularly across the Southern United States. They are frequently observed rummaging for food in yards or along roadsides, leading to casual comparisons. This shared habit of foraging in human-modified landscapes contributes to the mistaken belief of a close relationship.
Armadillos: Their Unique Lineage
Armadillos belong to the superorder Xenarthra, an ancient group of placental mammals primarily found in the Americas. This superorder also includes sloths and anteaters, their closest living relatives. Armadillos are highly adapted for digging, possessing strong claws and short, powerful legs well-suited for excavating burrows or unearthing food. Their diet consists of insects, grubs, and other invertebrates, though some species may also consume plant matter and small animals. Most armadillos are covered by a leathery, bony armor shell, which gives them their name, meaning “little armored ones” in Spanish.
Possums: A Different Branch of the Family Tree
The North American opossum is a marsupial. Marsupials are characterized by giving birth to relatively undeveloped young that complete their development outside the womb, often within a specialized pouch called a marsupium. The Virginia opossum is the only marsupial native to North America north of Mexico. Their closest living relatives are other marsupials found predominantly in Australia and the Americas, such as kangaroos and koalas.
Key Distinctions
Significant biological and behavioral differences clearly separate armadillos and possums.
Physically, armadillos are distinguished by their bony, segmented armor, which covers their backs, heads, tails, and legs. In contrast, opossums have grayish fur and a long, nearly hairless, prehensile tail that they use for grasping, balancing, and even carrying nesting materials.
Reproductively, armadillos are placental mammals, with the nine-banded armadillo notably giving birth to identical quadruplets. Possums, as marsupials, have a short gestation period of only 11-12 days, after which their tiny, undeveloped young crawl into the mother’s abdominal pouch to continue developing and nurse.
Their diets also vary. While armadillos are largely insectivorous, possums are omnivorous scavengers, known for eating a wide variety of foods including plants, fruits, insects, small animals, and carrion.
When threatened, armadillos may jump straight into the air or roll into a protective ball. Possums employ a different defense mechanism, famously “playing dead” by entering an involuntary, catatonic state.
Regarding locomotion, armadillos are quick diggers and can move surprisingly fast on their short legs, even crossing water. Possums are terrestrial animals that walk with a slow, deliberate gait, but they are also skilled climbers and decent swimmers, using their prehensile tails for balance.