The cow skulls have been cleaned and do not have lower jaws. They average 20" long and 8" wide. "Muley" means naturally hornless.
Cows are not an endangered species.
These skulls are a by-product of the meat industry. The animals were not killed just for their skulls. We cannot ship cow skulls to Canada because of concerns over BSE (Bovine Spongiform Encephalopathy).