| Answer | Crossword Clue |
|---|---|
| MIOCENE | Epoch in which grazing mammals became widespread |
| EOCENE | Epoch in which mammals became dominant |
| EOCENE | Epoch in which mammals arose |
| EOCENE | Epoch in which modern mammals emerged |
| EOCENE | Epoch in which modern mammals first emerged |
| IRONAGE | Era in which alphabetic writing became widespread |
