Horse evolution was previously believed to be a linear progress, but after more fossils were discovered, it was determined the evolution of horses was more complex and multi-branched. Horses have evolved from gradual change ( anagenesis ) as well as abrupt progression and division ( cladogenesis ).They concluded that horses evolved with the emergence of grasslands and an increase of predators. The digits of their early Eocene ancestor evolved into hooves.
Because amino acids can be arranged in many different combinations, it's possible for your body to make thousands of different kinds of proteins from just the same 21 amino acids. You may see books that say there are only 20 amino acids.
