Posts Tagged ‘glyptodonts’

Arthritic Glyptodonts

July 9, 2021

I am lucky so far. I am 59 years old and don’t feel arthritic yet, but my father was about my age when he first suffered from arthritis. The incurable disease forced him to give up playing tennis because his hand hurt too much when he tried to return a shot. About 50 million adults and 300,000 children suffer from arthritis. There are over 100 types of arthritis. The 4 most common include degenerative, infectious, inflammatory, and metabolic. Degenerative arthritis is caused by cartilage wearing away so that 2 different bones rub against each other at the joint. Bacteria cause infectious arthritis, and inflammatory arthritis is the result of the immune system turning against itself following an infection. Metabolic arthritis is caused by uric acid build up. This is the kind my dad had, and he also used to suffer terrible attacks of gout–a related condition.

Man isn’t the only animal that suffers from arthritis. Other primates, elephants, bears, and extinct ground sloths are known to be susceptible to the disease. Paleontologists examining bones of extinct glyptodonts found evidence of arthritic joints. Glyptodonts are related to armadillos. A recent genetic study found their closest living relative was the tiny pink fairy armadillo–an ironic discovery because fairy armadillos are so small, and glyptodonts weighed several tons. However, glyptodonts diverged from armadillos about 35 million years ago. The main difference between armadillos and glyptodonts is the shell. Armadillo shells in most species are flexible, and they can curl up in a ball when threatened. Glyptodonts had stiff turtle-like shells. The arthritic glyptodont bones were found in a limestone cave near Lajeda de Ecole, Brazil. Glyptodonts ranged throughout South America and into the southern parts of North America including coastal Georgia. The arthritic glyptodont specimen found in Brazil suffered from calcium pyrophosphate disease, a complication of spondyloarthropy. This disease is known as false gout because it is similar to gout, though the physiological cause differs. The specimen’s arthritis was in its arm and leg joints.

3 different species of glyptodonts compared to an average-sized man. I found this image on google. I don’t know who the original creator was.
Glyptodont joints with arthritis. Image from the below referenced paper.

Arthritic glyptodonts may have been more vulnerable to predators. When attacked, glyptodonts quickly turned around and swung their tails which in some species were clubbed. A glyptodont slowed by arthritis may have been too sluggish to swing their tail in time. Scientists found 1 specimen of arthritic glyptodont with gnaw marks from an extinct dog known as Protocyon trogylodytes. This predator may have killed the aged glyptodont or perhaps it scavenged an animal that died of old age.

References:

Aurauj-Junior, H. ; et. al.

“Overlapping Paleoinchnology, Paleoecology, and Taphonomy: Analysis of Tooth Traces in Late Pleistocene-Early Holocene Megafaunal Assemblage of Brazil and Description of New Ichnology in Hard Substrate”

Paleogeography, Paleoclimatology, and Paleoecology 468 2017

Barbosa, F. ; et. al.

“Arthritis in a Glyptodont (Mammalia, Xenartha, Cintulata)”

Plos One Feb 2014