It is Extremeley hard to find anything on animals of the tertiary period (if that is what you are refering to by"TERTIARY") Good luck though! It is Extremeley hard to find anything on animals of the tertiary period (if that is what you are refering to by"TERTIARY") Good luck though!

growth

Tertiary - Third

So the tertiary comes third.

Peptide Bonds!

At the beginning of the Tertiary period, mammals replaced reptiles as the dominant vertebrates. Each epoch of the Tertiary was marked by striking developments in mammalian life. The earliest recognizable hominoid relatives of humans, Proconsul and Australopithecus, also. Modern types of birds, reptiles, amphibians, fish, and invertebrates were either already numerous at the beginning of the period or appeared early in its history. Modern families of flowering plants evolved. Marine invertebrates and non-mammal marine vertebrates experienced only modest evolution.