 Complete the following phrase:  Chalicotheres can be first identified with certainty around 46 million years ago, in the Eocene of Asia. The family is thought to have evolved there, but appeared in North America by the Eocene. By the late Oligocene, they had divided into schizotheriines and chalicotheriines. Earlier chalicotheres are often referred to the family Eomoropidae; it is not yet clear whether they had claws or how the two subfamilies diverged. Both subfamilies were successful over many millions of years, and reached their greatest diversity in the Miocene. Advanced schizotheriines Moropus entered North America via the Bering land bridge at the Oligicene-Miocene boundary, and expanded southward into Central America. There were multiple radiations into Africa, where chalcotheriines were later replaced by schizotheriines. Both groups spread early into Europe. In the Pliocene, they would have faced new competition in North America from megalonychid ground sloths which emigrated from South America in the 