“In the course of his geologic studies, Darwin came across many fossils of extinct mammals. Among the most interesting to him were those of giant armadillos. Nowhere else in the world were surviving species of these strange armored mammals found. Was it only a coincidence that extinct armadillos were also found buried in these same South American plains? Here again Darwin encountered tangible evidence of change and history.”
from Biology, by Helena Curtis (Worth Publishers, Inc., 4th edition, pg. 882-883)
[Photo credit: Luiz Claudio Marigo/naturepl.com]
The giant armadillo is the largest existing armadillo species (it grows up to 1.5 meters in length (~ 5 feet), with a weight up to 25 kg (~ 60 lbs)), although the extinct glyptodont — which evolved during the Miocene era in South America — was considerably larger (close to the size of a Volkswagen beetle). At one time, the giant armadillo was spread over most of the tropical forests and grasslands east of the Andes, from Venezuela to Argentina; currently, due to over-hunting and the loss of habitat to human development and agriculture, the species is at risk of extinction.