Mammals evolved into larger organisms and began subdividing into various species in the

Mammals began subdividing into various species in the CENOZOIC ERA. Cenozoic era is the third major era of the earth history, the era began about 66 millions years ago until the present time. It is also called the age of mammals because mammals are the dominant specie during the era.

They create genetic variations

U. life is what you go through to become a better person. it makes you stronger, wiser, and more creative. it can be hard but its ok. because i believe everyone was put here for a reason. whether or not you know that reason you should always look towards the future and trust in god for a better tomorrow.be safe and blessed