The armadillo, Dasypus novemcinctus, is a small mammal covered with hard bony plates instead of ordinary skin across most of its back. This nine-banded armadillo lives across parts of North America, Central America, and South America.
A Body Built Like Armor
The back is its strangest feature.
Its armor is made from bony plates called scutes, covered by a layer of tough skin. The shell has a front shield, a rear shield, and movable bands around the middle of the body.
A nine-banded armadillo has 7 to 11 movable bands, despite its common name. The number of bands does not always equal nine.
The shell is gray to brown.
Its underside is softer and lacks the heavy bony armor found across the back. Sparse hairs grow around the belly and other areas of exposed skin.
The head is narrow and the snout is long.
Its tail is covered by rings of bony plates, while the front feet have four toes and the hind feet have five. Large curved claws give the animal the digging power needed to open burrows and search through soil.
A Small Mammal With a Heavy Shell
An adult nine-banded armadillo measures about 38 to 58 cm from the head to the end of the body, with the tail adding another 26 to 38 cm. Adults weigh about 2.5 to 6.5 kg, although individual body mass changes with age, sex, food availability, and season.
The animal looks heavier than it is.
Its armor can account for about 15 percent of the body weight in armadillos as a group, according to Animal Diversity Web.
The Ground Becomes a Pantry
Nine-banded armadillos feed mainly on small animals without backbones. Insects form a large part of the diet, while spiders, scorpions, snails, grubs, and other invertebrates also appear in its food.
It also eats eggs.
Small reptiles and other animal food enter the diet when available, while fruit, seeds, fungi, and other plant material make up a smaller part of the diet.
The nose does most of the searching.
Nine-banded armadillos have poor eyesight but a strong sense of smell. They walk with the snout close to the ground, sniffing for prey before using their claws to break through soil or leaf litter.
A Burrow Under the Roots
The nine-banded armadillo lives in forests, scrub, grasslands, savannas, and areas beside streams. It favors warm habitats with enough moisture because damp soil is easier to dig and contains more prey.
Rain matters.
Animal Diversity Web reports that the species is strongly associated with areas receiving at least 38 cm of annual rainfall. It also lives in the southeastern United States, Mexico, Central America, and large parts of South America.
Burrows provide shelter during resting periods.
A single burrow can contain several passages leading to an underground chamber, giving the animal more than one escape route when danger arrives.
Six Minutes Underwater
The armadillo is a better swimmer than its heavy shell suggests.
It can cross water by swimming at the surface or by walking along the bottom in shallow water. Animal Diversity Web reports that it can hold its breath for up to 6 minutes.
There is another trick.
The animal can swallow air and inflate its stomach and intestines, increasing buoyancy so it floats across the surface.
That strange behavior is especially useful when a stream blocks its path.
The Three-Foot Jump
A frightened armadillo does not always run.
When startled, it can jump almost straight upward, reaching about 3 feet in the air. This defensive reaction creates a serious danger near roads because the animal can rise directly toward the height of a vehicle bumper.
Roads are a major threat.
National Park Service observations identify vehicles as an important source of mortality, especially because the animal is active at night and its eyes do not reflect headlights like deer eyes.
Four Identical Babies
The reproductive system of the nine-banded armadillo has an unusual feature.
Females give birth to 4 genetically identical young from a single fertilized egg. This process is called monozygotic polyembryony.
All four young are the same sex.
Gestation lasts about 135 days after implantation, but the full period from fertilization to birth is longer because the embryo can remain in a delayed state before implantation.
Birth normally produces four babies.
Newborns weigh about 28.6 to 114 grams and have soft pink skin rather than the hard armor seen on adults.
The Armor Hardens After Birth
The babies develop their protective plates after birth.
Within several days, their skin begins to harden and form the dorsal armor that gives the species its adult appearance.
Young armadillos can walk shortly after birth.
At about 2 to 3 weeks old, they begin leaving the burrow for short periods with their mother. Weaning takes place at about 4 to 5 months.
Females reach sexual maturity at about 1 year.
A Mammal That Crossed Northward
The nine-banded armadillo originally had a range centered farther south in the Americas. Its range expanded northward through Mexico and into the southern United States.
It reached the United States long ago.
Today the species occurs across a large part of the southeastern United States, with its range extending farther north into parts of the Midwest.
Animal Diversity Web reports records as far north as Nebraska.
Predators Above and Beside the Road
Young armadillos face predators before their armor becomes fully developed.
Coyotes, bobcats, and alligators are among the predators listed by the National Park Service. Eggs and small reptiles are also part of the armadillo's diet, showing that its food web includes both prey and predator relationships.
Humans create a different danger.
Vehicle collisions kill armadillos across their range, especially during nighttime activity.
A Name From Spanish
The word armadillo comes from Spanish and means “little armored one.” The name fits the animal's bony shell rather closely.
The species name is different.
Dasypus novemcinctus was described by Carl Linnaeus in 1758, placing the species in one of the oldest formal systems of modern animal classification.
The nine-banded armadillo belongs to the order Cingulata.
A Mammal That Carries Its Shelter
The armor protects the upper body while the claws handle another problem: soil.
Its forelimbs contain powerful muscles attached to modified bones, while the long claws break through hard ground and leaf-covered soil. The animal spends large parts of its active time searching for food close to the surface.
It is mostly solitary.
The nine-banded armadillo is primarily nocturnal and spends daylight hours inside burrows or other sheltered locations. Its sense of smell guides it through the dark more effectively than its weak eyesight.
One animal can have more than one burrow.
The same individual can move between underground shelters as conditions change, keeping its feeding area connected to places where it can escape quickly.
A Species Still Moving North
The nine-banded armadillo is not listed as endangered.
Its broad distribution and ability to use forests, grasslands, scrub, and areas near water have helped it occupy habitats across a large part of the Americas.
But the northern edge of its range is still changing.
Scientists continue to study how temperature, habitat changes, food supply, and predators affect this expansion.
For an animal wearing a shell, the biggest danger can still arrive on four wheels.
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