The Cenozoic is the age of mammals.
It was during the Cenozoic that these lifeforms proliferated:
- Grasses
- Flowering plants
- Birds
- Rodents
- Snakes
Also, Antarctica developed its ice sheet through most of the Cenozoic.
Depending on if this makes an outlier, or if it is not. If it is then it will change the mean a good bit positive or negative depending on if it is it being a high or low outlier. The median will not be as effected by this new number because it will only move one point in either direction.