Among the best known marine animals are whales, even a small child recognizes them after seeing them in a book, television or a caricature. And how not to do it? These giants are unmistakable, cause some people panic because of their large size while others arouse fascination.
Like the dolphins, they are cetaceans, an order of aquatic mammals. One of the main characteristics of mammals is that they have mammary glands to feed their young, like us humans. In fact the milk of the whales has so much fat that it does not dissolve easily in the water, so the calves (baby whales) can feed.
What if I told you that the evolutionary ancestors of whales walked on earth? Would you believe me?
Whales as we know them exist for more than 50 million years, but one theory says that their ancestors were land animals that began to inhabit the water. Maybe because of the lack of food or the temperatures, like the hippos that spend most of their time in the water to withstand the heat of Africa. Over time, their bodies adapted, changing their front legs by fins and their hind legs by caudal fins, both of which even conserve the bones that used to be fingers.
This theory is based on scientific discoveries of the last decades when studying skull fossils. This research was led by the American paleontologist and biologist Phillip D. Gingerich, even today there are many things to discover and continue to be investigated.
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Another of the bases of this theory are the vestigial organs that still possess the cetaceans, near their tails is a floating bone that was previously their pelvis, it is quite obvious that an exclusively aquatic animal would not need it. Simply incredible!
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