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.
245 to 208 million years ago. 1  During the Triassic period, all land on Earth existed as one enormous mass. It was called Pangaea. 2  Some reptiles, frogs, turtles and crocodiles existed earlier, but dinosaurs didnât appear until late in the Triassic period. 3  The period marked the rise of small, lightly built dinosaurs. The first mammals evolved during the Triassic period. Most of the plants that existed were evergreens. The period ended with a mass extinction that wiped out most animals and reptiles. An entire order of plants or animals dies out in a mass extinction. The dinosaurs that survived flourished in the next period, the Jurassic. Dinosaurs that lived during the Triassic period include: