The National SAFEKIDS Campaign recommends that no child under the age of 12 be left at home alone. However, consider a child's age and maturity level. For example, if a child is extremely impulsive, it might be best to wait until he or she is older than 12.
Did people and dinosaurs live at the same time? No! After the dinosaurs died out, nearly 65 million years passed before people appeared on Earth. However, small mammals (including shrew-sized primates) were alive at the time of the dinosaurs.
Life in the Tertiary Era On land, the age of the mammals was beginning. Rodents evolved, as well as gliding mammals and the early primates. Sharks and fish took over from marine reptiles. Towards the middle of this Era, the ancestors of elephants, horses, cattle, pigs, rhinos and deer appeared.eological Time Periods. The time periods are very important to a palaeontologist. The table below is a very simple Geological Time Line. Click on the time period you wish to invisigate.