Popi's Whales

Whales are a diverse group of aquatic placental marine mammals.

They are divided in different categories: Baleen Whales, which include on one side the Right whales and the Pygmy Right Whale, and on the other the Rorquals and the Grey Whale. Toothed Whales, which include on one side the Sperm whales and on the other different types of dolphins and beaked whales (Beaked whales, River Dolphins, Beluga and Narwhals, Porpoises, Dolphins).

Whales, dolphins and porpoises belong to the Cetartiodactyla, which consists of even-toed ungulates. This is because their ancestor, the Pakicetus, a four-legged, goat-sized creature used to walk the earth. They eventually migrated to the water for hunting reasons and evolved to cope with their new environment. Some whales still have leftovers of the back-leg's bones.

Their ears are different from terrestrial mammals to be able to hear underwater.

Their tiny ear is made so that it can close underwater and produces layers of earwax that form a sort of earplug that actually works as a hearing aid: The similar densities of water and the earwax allows sound to travel into the ear unhindered (which wouldn't be possible if the ear was filled with air!).

The layers can be colored differently because of the keratin in the wax, which is influenced by the periods of migration or the feeding habits of the whale. This means you can learn a lot about a whale's age, migrations and eating habits by looking only at their earwax!

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