The armadillo, the armor-clad mammal that meanders through the Americas, has long piqued the curiosity of nature enthusiasts. Wrapped in a suit of impenetrable bony plates, armadillos have adapted for survival in a wide array of environments, from rainforest to desert.
Yet, behind their shield lies many an interesting fact—did you know these seemingly solitary mammals can give birth to identical quadruplets? Or that the nine-banded armadillo is the only species that inhabits the United States?
Read on to uncover the diverse species of armadillos, marvel at their unique feeding habits, and explore how the distinctive structure of their armor is both advantageous and limiting.
11 Facts About Armadillos For Curious Minds
1. Armadillos are covered with bony plates called “scutes”
When we think of armadillos, we think of the armor covering their bodies. This distinctive body armor comprises bony plates, or osteoderms, which fuse with their skin to create protective scutes. These scutes cover the armadillo’s head, back, tail, and sides. However, they vary in number and rigidity among species, accommodating their needs for flexibility and movement.
Armadillos have evolved these special overlapping plates over millions of years to protect themselves from predators and environmental hazards. Interestingly, this armor is primarily made of keratin1, the same protein found in human hair and nails.
An armadillo's underbelly remains unarmored and features coarse, sparse hairs for insulation and sensory purposes. Armadillos can also shed and regrow their scutes, repairing damage or accommodating their growth.
2. Armadillos are terrific diggers
The nocturnal armadillo has developed excellent digging skills to help it survive in the wild5. They can easily dig through soil and create elaborate burrow systems using their strong, curved claws on their front and hind legs.
These underground burrows protect them from predators and provide them with a comfortable resting environment with stable temperature and humidity levels. While digging, armadillos use their snouts to loosen the soil, and their powerful front claws effectively shovel the dirt out of the way.
Armadillos rely on an impressive sense of smell to detect insects and other invertebrates underground for food.
3. Armadillos are agile swimmers that can inflate their stomachs to float
Another interesting fact about armadillos that separates them from other mammals is their remarkable swimming ability. Armadillos inflate their stomachs to help them navigate rivers, ponds, and other bodies of water!
Armadillos float by gulping air, providing them with the buoyancy that allows them to glide easily across the surface of the water2. As they paddle with their front and hind limbs, they can effectively avoid any obstacle on the water.
Not only are armadillos skilled swimmers, but they're also relatively fast on land. Some species of armadillo, such as the nine-banded armadillo, can sprint at speeds of up to 30 mph. Their quickness helps them dodge predators and navigate their surroundings efficiently.
4. Armadillos are insectivores that can also enjoy small vertebrates, fruits, and plants
As solitary animals, armadillos spend much of their day foraging alone. Primarily, armadillos eat insects, skillfully using their keen sense of smell to locate ants, termites, and other insects.
While digging into the soil with their sharp claws, they find underground insects and devour them with their long, sticky tongue. Armadillos can consume thousands of insects in one sitting, helping to regulate insect populations and maintain ecological balance.
Although insects are their favorite food, armadillos aren't picky eaters. They are opportunistic feeders, so they eat whatever is available in their area. For instance, they also eat small vertebrates like amphibians, reptiles, and mammals when the chance presents itself. An armadillo's diet even extends to tubers, roots, foliage, and fruits native to their habitat, like berries and melons.
These diverse eating habits contribute to the health of the armadillo’s ecosystems. When they eat plants, armadillos disperse seeds around the soil. Meanwhile, digging through the soil promotes soil aeration, allowing it to support more organisms.
5. Female armadillos give birth to unique identical quadruplets in a single litter
One interesting aspect of armadillo reproduction is the birth of unique identical quadruplets in a single litter. This phenomenon occurs mainly in the nine-banded species. Polyembryony involves a single fertilized egg divided into four embryos with the same genetic material. As a result, the quadruplets are either male or female, with identical genetic makeup.
Nine-banded armadillos usually have a gestation period of around 120 days. Then, the female gives birth to a litter of four pups, all covered in soft, leathery skin.
This skin gradually transforms into protective armor within the first few weeks after birth. While this happens, the mother armadillo cares for her young, teaching them essential skills such as foraging, digging, and navigating their environment. Eventually, the baby armadillos become independent and venture out on their own.
6. The three-banded armadillo curls up into a ball for protection
The three-banded armadillo is unique among armadillo species because of its remarkable defensive ability. It curls up into a protective ball to protect itself from danger.
Notably, the Brazilian three-banded armadillo (Tolypeutes tricinctus) and the Southern three-banded armadillo (Tolypeutes matacus) are the only armadillo species that form themselves into tight balls for protection, using their specialized armor against predators like birds of prey or big cats4. Other armadillos simply burrow into the ground or seek cover when threatened.
How does the three-banded armadillo do this? First, it retracts its head and limbs, which curls its flexible armor over its soft underbelly. The armor comprises three bands (hence their name), forming armadillo shells that cover their entire bodies. In one move, the animal creates a near-impervious shield against all attacks. Remarkably, its head and tail fit seamlessly into this defensive posture.
Three-banded armadillos develop this vital survival skill early on. As their armor begins to harden, the pups start practicing rolling into a ball, a fascinating example of animal adaptation.
7. Armadillos have gestation periods of 60 to 120 days, depending on the species
Depending on species or body size, armadillos have different gestation periods. Smaller species, like the pink fairy armadillo (Chlamyphorus truncatus) and the six-banded armadillo (Euphractus sexcinctus), typically have gestation periods of 60 days. Since they have shorter gestation periods, they can reproduce quickly and grow their population more rapidly, helping them sustain their population despite environmental challenges. However, their young might need extra care due to this rapid reproduction rate.
On the other hand, larger species, such as the giant armadillo (Priodontes maximus) and the greater long-nosed armadillo (Dasypus kappleri), have gestation periods of 120 days. Forming their larger and more complex body armor requires an extended development time to proceed properly. Moreover, a longer gestation period often results in offspring that are better prepared for survival shortly after birth.
8. Armadillo young develop their armor weeks after birth
At birth, armadillo pups have soft, leathery skin that provides only minimal protection. Within hours, though, this skin begins to harden. Then, a strong suit of armor made of keratin starts to replace its original skin over the next several weeks. Their armor also grows as the pups grow. New scutes form, and existing ones expand to accommodate the changes in their bodies.
The hardening process varies among the 21 species; some develop their armor more quickly than others. Their heads and tails are also covered with protective plates, leaving no gaps against predators and environmental hazards.
While armadillo pups might be vulnerable, they can already move around as soon as they are born. They can follow their mother and learn essential survival skills while waiting for their armor to form. By the time they are weaned and ready to venture out on their own, the pups' armor will have fully developed. They now have the protection they need to survive in the wild.
9. People hunt armadillos for their meat and shells
People in the Americas practice armadillo hunting, a culturally significant tradition in South America, Central America, and the southern United States. They hunt these animals for their meat and shells, which they use for various purposes. For example, armadillo meat has a distinctive flavor and texture, making them sought-after ingredients for traditional stews, soups, and roasts.
Moreover, some communities believe armadillo meat has medicinal properties, further boosting its popularity.
Besides their dietary importance, armadillos are important materials for local handicrafts. Locals have used their carapaces, or dorsal sections of the shells, to make bowls or containers. They also carve the scutes into intricately designed ornaments.
While recognizing the cultural importance of armadillo hunting, we must also be aware of the potential effects of excessive hunting on the animal population. Therefore, it is essential to advocate for sustainable practices. A few examples are implementing regulated hunting seasons, promoting alternative sources of income, or developing educational programs.
10. Some armadillo species are vulnerable to habitat loss
The International Union for the Conservation of Nature (IUCN) has classified most armadillo species, like the common nine-banded and the screaming hairy armadillo, as “Least Concern,” which indicates a low risk of extinction.
However, other armadillo species, like the giant armadillo and the pink fairy armadillo, are threatened by habitat loss, earning the designation of "vulnerable species."
Humans have destroyed and fragmented the natural habitats where armadillos live through deforestation, agriculture, urbanization, and infrastructure development. With reduced habitats, these armadillos face a limited food supply and lower chances for survival.
The largest species are the giant armadillos, and they are a prime example of this vulnerability. Over the years, the giant armadillo has seen a sharp population decline, thanks to habitat loss and poaching for their meat and shells. Noting this decline, the IUCN Red List has labeled it as "Vulnerable.”
On the other hand, one of the smallest species is the pink fairy armadillo, listed as "Data Deficient" on the IUCN Red List. This classification indicates a need for more sufficient information to assess its conservation status accurately. However, experts believe that agricultural expansion in its native Argentina is the biggest threat to this creature. They are also concerned with the long-term health of the armadillos’ ecosystems because of these creatures’ significance in maintaining balance in these environments.
11. Armadillos can contract and transmit leprosy
Nine-banded armadillos have become major contributors to leprosy research thanks to their ability to contract and transmit the disease. The bacterium Mycobacterium leprae can thrive in an armadillo's body because of its low body temperature, which resembles that of humans.
The first case of an armadillo contracting leprosy was recorded in the 1970s. Since then, researchers have gained valuable insights into the disease’s host-pathogen interactions and the factors affecting vulnerability. Studying armadillos has enabled scientists to develop and test new diagnostics, treatments, and vaccines for leprosy, which has profoundly affected human life for years.
Moreover, experts have observed many cases of armadillo-to-human transmission of leprosy3, particularly in the southern United States. While the study of armadillos for leprosy research does raise ethical questions, their contributions to the field have undeniably been vital. Without these animals, humans would remain unable to widen existing knowledge and enhance treatment options for those afflicted by the disease.
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