Citation: Tarsi, K. & Tuff, T. (2012) Introduction to Population Demographics. Nature Education Knowledge 3 (11):3 How do we know if a species is heading towards extinction?

Computational Biology: Bioinformatics; Sequence and structure databases; DNA, RNA and protein sequence analysis; Secondary structure and 3D structure prediction ... Three Dimensional Geometry; ...

An all-time high of 72 agencies are on this year's Power List, an annual collection of the world's biggest sellers of travel.