The Evolution Of Whales
Intraspecific evolution in whales
The evolution of whales has long been disputed, this is due to many missing links in both the fossil record and DNA analysis. It is believed that whales as a whole evolved from insectivore creodonts. From this group three branches occurred. Archaeocetes - Extinct, Odontocetes – Extant and Mysticetes – Extant. Of the two extant groups we know they took separate paths at evolving and did not evolve from each other as they are so dissimilar it is apparent they have always been separate and distinct from each other since ancient times (Tinker, 1988). Archaeocetes are said to have evolved in the Mesozoic era, however there is no fossil evidence of this. The earliest fossils of Archaeocetes appeared in the early
Eocene Epoch (Tinker, 1988). The fossils found from this time showed that these ancient whales were already well adapted to life under water. They had very primitive features compared to modern whales though. They still had a bilateral skull and the “blowhole” or nostrils were still very frontal to the face.
The evolution of whales has long been disputed, this is due to many missing links in both the fossil record and DNA analysis. It is believed that whales as a whole evolved from insectivore creodonts. From this group three branches occurred. Archaeocetes - Extinct, Odontocetes – Extant and Mysticetes – Extant. Of the two extant groups we know they took separate paths at evolving and did not evolve from each other as they are so dissimilar it is apparent they have always been separate and distinct from each other since ancient times (Tinker, 1988). Archaeocetes are said to have evolved in the Mesozoic era, however there is no fossil evidence of this. The earliest fossils of Archaeocetes appeared in the early
Eocene Epoch (Tinker, 1988). The fossils found from this time showed that these ancient whales were already well adapted to life under water. They had very primitive features compared to modern whales though. They still had a bilateral skull and the “blowhole” or nostrils were still very frontal to the face.