Extinct Glyptodonts Were Gigantic Armadillos Say Scientists

Posted on February 23, 2016

Two male glyptodonts in battle

Extinct ancient glyptodonts were actually gigantic armadillos say scientists citing new DNA evidence. The DNA study also reveals that the huge armored mammals originated later than previously thought. Glyptodonts went extinct at the end of the last ice age. The illustration above shows a battle between two male glyptodonts.

The international team of researchers say glyptodonts likely originated less than 35 million years ago from ancestors within lineages leading directly to one of the modern armadillo families. Some species of glyptodonts may have weighed over two tons. The closest modern relatives include the giant armadillo (which weighs up to 25 pounds) and the tiny four-ounce pink fairy armadillo.

Hendrik Poinar of McMaster University, a co-author of the study, says in a statement, "Ancient DNA has the potential to solve a number of evolutionary questions, but it is often extremely difficult to obtain endogenous DNA, that is, DNA actually belonging to the animal being sampled, rather than some contaminant. In this particular case, we used a technical trick that allowed us to selectively enrich our Doedicurus DNA extract so that we had enough endogenous genetic material to work with."

The cause of the disappearance of the large armadillos remains a mystery. Climate change and humans are a couple of the current theories.

Ross MacPhee, a curator in the American Museum of Natural History's Department of Mammalogy, says, "Despite their ungainly appearance, different species of glyptodonts occupied habitats as distinct as open grassland and dense woodland, all the way from Patagonia to the southern parts of the continental United States. Although their disappearance has been blamed on human depredation as well as climate change, some species persisted into the early part of the modern or Holocene epoch, long after the disappearance of mammoths and saber-toothed cats. Like the loss of giant ground sloths, mastodons, and dozens of other remarkable mammalian species, the precise cause of the New World megafaunal extinctions remains uncertain."

A research paper on the study was published here in the journal, Current Biology. The image below shows a glyptodont on display in the American Museum of Natural History's Hall of Primitive Mammals.

Glyptodont on display at the American Museum of Natural History


Illustration: Peter Schouten
Photo: AMNH/ D. Finnin