Horse
The horse adapted to survive in areas of wide-open terrain with sparse vegetation, surviving in an ecosystem where other large grazing animals, especially ruminants, could not. Horses and other equids are odd-toed ungulates of the order Perissodactyla, a group of mammals that was dominant during the Tertiary period. In the past, this order contained 14 families, but only three—Equidae (the horse and related species), Tapiridae (the tapir), and Rhinocerotidae (the rhinoceroses)—have survived to the present day.
Egernia
It is the namesake genus of the "Egernia" genus-group, which also includes the Solomon Islands skink ("Corucia"), "Cyclodomorphus" and the blue-tongued skinks ("Tiliqua"). In some older works, it is considered closely related to "Mabuya", but even among the subfamily Lygosominae this genus does not seem to be particularly closely related and would—were the genus-groups treated at the rarely used rank of infrafamily—certainly constitute an infrafamily of its own. On the other hand, the enigmatic crocodile skinks ("Tribolonotus") might be a very basal member of the "Egernia" genus-group.