From land animal to whale
On the left, you can see what whales looked like 50 million years ago. It was a long way from the land-based primeval whale to the whale of today. The animals had to adapt to life in the water little by little. Can you describe what has changed? What happened to their legs, tail, fur, ears and nose? How did the body shape change? In the following video you will find the answer.
Adaptations to life in the water
Evolution
Of course, the changes did not happen quite as quickly and in succession as in the explanatory video. It was a long process that lasted more than 10 million years.
You can clearly see from the primeval whales how the appearance and behaviour of the animals gradually changed.
The Pakicetidae (1) were still land animals and their appearance reminded a little bit of a wolf. They found their prey in shallow water. In the Ambulocetidae (2) the tail and legs are already stronger, which made it easier for this ancient whale to move in the water.
Even better adapted to the life in the water were the Remingtonocetidae (3). They had long snouts and probably already actively hunted for fish, similar to today's otters. The Protocetidae (4) were very good swimmers and had a shorter neck which was better suited for diving. Muscles had formed on the tail.
Now the primeval whales already look similar to today's whales and dolphins. The Basilosauridae (5) had only tiny hind limbs. Their nostrils had already moved further back, but for breathing they probably still stuck out their head. The long, slender body was very suitable for hunting in shallow bays. The Dorudontinae (6) lived at the same time as the Basilosauridae. They also had tiny hind legs, but were much smaller. The Dorudontinae are thought to be the origin of today's whales and dolphins. The suffix -nae indicates that Dorudontinae are only a subfamily. For a long time they were considered to belong to the Basilosauridae family, but this is now doubted.