Over time seals were chased off land due to an increase in wolves who were hunting them. The seals moved into the water.
Oh man I am sure glad for these great lungs.
The population of seals were split between grey seals and tan seals. The grey seals had a larger lung capacity which gave them a distinct advantage over the tan seals as they could be underwater for longer therefore they could hunt much better. The tan seals were either out competed for food in the sea or were forced back on land were they were prayed upon by wolves.
Generations passed and the only kind of seals left were gray seals as they were the only ones who were able to live long enough to re produce.
The seals were chased of land due to increased wolf population who were hunting them. Both the tan seals and the grey seals began to live in the water.
Hey I can feel my lungs getting larger.
The grey seals had better lung capacities and at first they were able to outcompet the tan seals for food. However the lungs of the tan seals began to expand to fit their needs and the tan seals became equal hunters to the grey seals.
The two types of seals were able to survive to reproductive age. The tan seals were able to pass on their lung capacity to their children. Therefore the two speeches were able to coexist in the water.After many years the wolves eventually left due to a shortage in pray therefore some seal went back to land and there lung shrunk back down to normal size.