Biology Reference
In-Depth Information
Following a gestation of about 120 days after implantation, these are usually born in March in a burrow
with an enlarged chamber. This chamber, which serves as both birthing room and nursery, is filled with
soft plant material such as grass and leaves.
The baby armadillos look exactly like miniature adults. They can walk after only a few hours and
begin to follow their mother on her rounds in just a few weeks. Although they nurse for only about two
months, they continue to stay with their mother for a few additional weeks before going off to live on
their own. They'll be mature by the next summer and will breed at that time.
Armadillo oddities seem to have no end. Consider the creature's behavior when it encounters a
stream. Although, as might be expected, an armadillo lacks buoyancy because of its armor, one can hold
its breath for up to six minutes—an adaptation that evidently helps it avoid inhaling dirt and dust while
digging burrows. When an armadillo comes to a stream that isn't excessively wide, it simply wades in
and walks along the bottom to the far side. But what of wider waterways? That's no problem: the ver-
satile armadillo just sucks in air and inflates its digestive tract. Then, with this extra buoyancy, it swims
across with ease. Medieval knights in full armor undoubtedly fared far worse than this resourceful little
creature when they were pitched off their chargers into deep water!
Both medieval knights and Spanish conquistadors no doubt boasted of their distinguished ancestry,
but armadillos can claim a vastly longer lineage. The earliest known ancestors of today's armadillos
date back some 55 million years—only about 10 million years after the demise of the dinosaurs. In
time, quite a diverse array of armadillos and their close relatives evolved, some of them quite astonish-
ing.
For example, within the past million years, during the Pleistocene Epoch, there was an enormous
armadillo called
Chlamytherium.
This great creature, which was herbivorous, had the bulk of a rhino-
ceros. Far more recently the so-called giant armadillo
(Holmesina septrionalis)
inhabited Florida.
Although far smaller than
Chlamytherium,
this armadillo was nonetheless huge compared with our
present-day specimens, for it was six feet long and weighed an estimated six hundred pounds. There
were humans in Florida by eleven thousand years ago, and the giant armadillo survived for at least an-
other twelve hundred years, so early humans must have actually encountered this hulking fellow.
Perhaps even more fascinating than these ancient armadillos is a branch of their family tree known
as
glyptodonts.
Also known as “turtle armadillos” because of their superficial resemblance to turtles,
glyptodonts had a carapace, or single large plate, that covered their entire upper side, making them just
as inflexible as turtles. In turtle fashion, they also could retract head and neck inside the protective shell.
One of these glyptodonts was truly gigantic: it was fourteen feet long and towered an astounding fif-
teen feet high! Despite its vast bulk, however, this perhaps wasn't the most bizarre of the glyptodonts.
That prize probably belongs to the creature known as
Doedicurus.
Doedicurus
must have presented an amazing sight. Along with its inflexible shell, it had a long, stout
tail that tapered outward and terminated in a large, spiked ball. No doubt this creature lashed its en-
emies with this potent weapon, much as knights of yore clobbered each other with maces!
