According to evolutionary theory, the whales of today had evolved from mammalian creatures that roamed the earth long ago. This was based on the evidence found from 53 million year old fossils of whale like semi - aquatic mammals. It was thought that the process from these creatures to change to whales actually took around 15 million years but a new discovery has found that it only took around 4 million years instead.
This new time line came about when a fossil from the oldest known whale was recently found in Antarctica. A 24-inch-long (60-centimeter) jawbone of this whale was recently discovered in a rich deposit of fossils on the Antarctic Peninsula. This early whale swam in the polar waters during the Eocene period, approximately some 49 million years ago. It's age suggests that fully aquatic whales had evolved from their mammalian ancestors much quicker than was previously believed.
The whale was similar in body structure but had a mouthful full of sharp teeth which were used to consume sharks, big boney fish and giant penguins. Their remains were discovered also along with the jawbone. The whale most likely reached up to lengths of 20 feet. The continent of Antarctica was at that time very green, with thick forests that marsupials and the mammalian survivors from the dinosaur age lived in. Even the surrounding waters were much warmer than that of today and were able to sustain the leather-back turtles and a quite diverse shark population. The shores of the continent were inhabited by large colonies of penguins including that of the giant penguin.
As soon as the predecessors of the whale became fully marine animals, they were populated all over the world and eventually developed into the species of whales that we are familiar with today. Some of these current species are now in jeopardy from human whaling activities from around the world. Considering their ancient beginnings from millions of years ago, it is quite sad that a newcomer in comparison (man) is the one responsible for the endangered status of many whales today.
This new time line came about when a fossil from the oldest known whale was recently found in Antarctica. A 24-inch-long (60-centimeter) jawbone of this whale was recently discovered in a rich deposit of fossils on the Antarctic Peninsula. This early whale swam in the polar waters during the Eocene period, approximately some 49 million years ago. It's age suggests that fully aquatic whales had evolved from their mammalian ancestors much quicker than was previously believed.
The whale was similar in body structure but had a mouthful full of sharp teeth which were used to consume sharks, big boney fish and giant penguins. Their remains were discovered also along with the jawbone. The whale most likely reached up to lengths of 20 feet. The continent of Antarctica was at that time very green, with thick forests that marsupials and the mammalian survivors from the dinosaur age lived in. Even the surrounding waters were much warmer than that of today and were able to sustain the leather-back turtles and a quite diverse shark population. The shores of the continent were inhabited by large colonies of penguins including that of the giant penguin.
As soon as the predecessors of the whale became fully marine animals, they were populated all over the world and eventually developed into the species of whales that we are familiar with today. Some of these current species are now in jeopardy from human whaling activities from around the world. Considering their ancient beginnings from millions of years ago, it is quite sad that a newcomer in comparison (man) is the one responsible for the endangered status of many whales today.
Is this peer-reviewed?