Somehow this humorous tale seems to fit the armadillo rather well. It is, after all, a rather odd-looking beast; the only mammal with a true shell must have looked nearly as strange to the early Spanish explorers as the duck-billed platypus did to the first European who spotted one. The name “armadillo”, or “little armored thing”, does originate from the Spanish conquistadores. The Aztec name was Azotochtli, which means “turtle-rabbit.”

The British author Rudyard Kipling wrote in one of his “Just So Stories” for children that the armadillo was actually born out of an alliance between a turtle and a hedgehog. This tongue-in-cheek story explains that to escape the jaguar, the turtle taught the hedgehog how to be less prickly and more armored, and the hedgehog taught the turtle how to curl up into a protective ball. The end result was the first two armadillos, which thoroughly confused the hungry jaguar.

We know today that armadillos are not turtles, hedgehogs, rabbits, or any cross between these animals. The armadillos belong to the order Cingulata, family Dasypodidae. Their closest living relatives are sloths and anteaters. Together, armadillos (order Cingulata) and sloths and anteaters (order Pilosa) make up the superorder Xenarthra. These animals first evolved around fifty million years ago, in what is now South America.

Glyptodon and Panocthus: Ancient armadillos

The earliest armadillo-like creatures were the glyptodon and the panocthus. (If you have seen the movie Ice Age, you have probably seen a glyptodon, at least in cartoon form!) These animals were quite large, about the size of a Volkswagen Beetle. They were also very heavily armored. While modern armadillos have become much smaller, they do retain the shell that first appeared in these ancient armadillo relatives.
 

Isolated from the rest of the world, and protected from predators with their bony armor, the armadillos flourished. They were relatively safe from predation; that is, until a land bridge developed between North and South America. Large canine and feline predators moved southward along this bridge, wreaking havoc on the native South American animals. Fossil records show that around seventy percent of the indigenous South American mammals were destroyed. The armadillos were not immune to these new and larger predators — although their shells are made of bone, they are rather thin — even a medium sized dog would have little trouble biting through.

Despite all of the pressures caused by the influx of North American predators, the ever-resilient armadillo was not completely eradicated. In fact, the animals staged a counter-attack, moving northward as far as the Ohio river valley. The most widespread of these was the beautiful armadillo(Dasypus bellus), which was nearly identical to the modern nine-banded armadillo in appearance — except the beautiful armadillo was much larger, nearly three times the size of the nine-banded armadillo. Fossilized scutes (the bony plates that make up the shell) from the beautiful armadillo have been found throughout the midwestern United States.

The beautiful armadillo held onto this territory until about eleven thousand years ago, when for unknown reasons all of the North American armadillo species became extinct. It was not until about 1850 that armadillos re-established themselves north of the Rio Grande. Since then, they have spread throughout the southeastern and midwestern United States, from North Carolina north to central Illinois, and as far west as New Mexico. Further northward expansion has been hampered by the animal’s low resistance to cold temperatures; they have almost no body fat reserves, and must forage for insects constantly. Cold weather means no food; no food means no armadillos. Even short periods of freezing temperatures can be fatal. However, they have had no problems with moving into warmer areas; current population estimates show between 30 to 50 million armadillos in the United States alone. For more information on the recent expansion of armadillos into the United States, see theArmadillo Expansion page.

Modern Armadillo Species

Twenty species of armadillo exist today. The most numerous one (and the only one found in theUS) is the nine-banded armadillo (Dasypus novemcinctus). Others include the giant armadillo (Priodintes maximus), the tatouay (Cabassous tatouay), the six-banded armadillo (Euphractus sexcinctus), the three-banded armadillo (Tolypeutes tricinctus — the only armadillo that can actually roll itself into a ball), the little hairy armadillo (Euphractus vellerosus), and the pink fairy armadillo (Chlamyphorus truncatus). The endangered pink fairy armadillo has a very unusual shell. It is only attached to the animal along the spine, forming a sort of shield over the rest of the body. It also has an unusual tail, tipped with a shovel-like plate. This burrowing armadillo, with its large front feet and very hairy sides, resembles a cross between a mole and a scaly-backed pink caterpillar. For more information on these and other armadillos, see the Armadillo Species page.

While armadillo habitat is limited by temperature it remains expansive.  The Nine-banded armadillo, one of 19 species of armadillos, is found throughout several continents including South, Central and North America, and is the only species of armadillo found in North America.  Armadillo habitats for all species are found as far south as Argentina in South America with the Nine-banded varieties extending as far north as Oklahoma and into Missouri in North America.

Armadillo habitat is not limited by water as a physical barrier.  A relatively new resident of the United States, the armadillo arrived here around 1850 by crossing the Rio Grande River from Mexico into Texas.  Based on their physical appearance it is hard to believe that this armored creature can swim for long distances but they have a rather interesting trait that allows for them to cross rivers-they can hold their breath!  Scientists have determined that the armadillo can inflate its stomach and intestines by pulling in air, thereby increasing its buoyancy and allowing it to float across wider rivers.  Additionally, an armadillo can simply hold its breath in its lungs, like you and I, and walk across the bottom of narrow streams, thus creeks and streams do not adversely affect the armadillo habitat.

Though, the state of Florida makes an inviting habitat for the armadillo, their presence there has been attributed mostly to those that have escaped from zoos and traveling circuses. The territory of those two (2) populations has merged into one (1) widening range consequently expanding the armadillo habitat greatly.    

Armadillos live in temperate and warm habitats, keeping them from expanding their range beyond the southern regions of the US. Having a lower body temperature than most mammals they cannot tolerate long periods of cold weather. They tolerate short periods by hiding in their underground burrows. The Nine-banded armadillo will begin to shiver at about 71 degrees Fahrenheit. The earth around a cozy burrow, however, keeps things a bit warmer than the outside and as such allows the armadillo to inhabit areas further north that have milder winters.  That said, it has been determined that the armadillo will not be able to survive in a climate where the average January temperature gets much below freezing.

The amount of rainfall in the area is also important to determining armadillo habitat.  It has been estimated that they prefer to live in climates that provide up to 38 cm of rainfall annually.  Reasons for this have been hypothesized to include associations between rainfall amounts and the quantities of food available, and the effect rainfall has on soil conditions.  As long as sufficient food and water supplies are available, Nine-banded armadillos are very adaptable to many different habitats.

Because they dig for both food and shelter the armadillo is very particular about the soils that it inhabits.  Armadillos will prefer your yard and gardens if the soil is soft and/or you have rotting wood nearby (rotting wood will be home to ants and termites that the animal finds irresistibly delicious!). Sandy soils are preferred over clay because the heavy clay soils make digging more difficult. The naturally shallow and rocky soils found in central Texas make very attractive Nine-banded armadillo habitats.