About Whales
Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. They are an informal grouping within the infraorder Cetacea, which usually excludes dolphins and porpoises. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates. Their closest non-cetacean living relatives are the hippopotamuses, from which they and other cetaceans diverged about 54 million years ago.
Type of whales
The two parvorders of whales,
baleen whales (Mysticeti)
toothed whales(Odontoceti)
Whales consist of eight extant families:
Balaenidae (right whales)
Cetotheriidae (the pygmy right whale),
Eschrichtiidae (the grey whale)
Monodontidae (belugas and narwhals)
Physeteridae (the sperm whale)
Kogiidae (the dwarf and pygmy sperm whale), and
Ziphiidae (the beaked whales).
10 amazing facts about the whales:
1. Cetaceans evolved from terrestrial (land) mammals!
Their ancestors were ungulates (e.g., cows, pigs) that adapted to foraging in marine water. In fact, the closest living relative of cetaceans is the hippopotamus!
2. Since cetaceans are mammals, they breathe air
They are also known as conscious breathers – this means they actively decide when to take a breath, unlike humans who are involuntary breathers. But how do they sleep if they need to consciously breathe? Cetaceans can “shut down” one side of their brain at a time, resting at the surface, while the other half of the brain is alert to keep them breathing. They will rest for just a few hours at a time and switch between the two sides of their brain.
3. Whales are the largest animals to have ever lived – even larger than any dinosaur!
Blue whales are the largest animals on the planet; they are as long as three back-to-back school buses and have a heart the size of a small car
4. There are two types of cetaceans.
The two types are toothed whales, which includes dolphins, beluga whales and narwhals; and the larger baleen whales, such as humpback and North Atlantic right whales. Toothed whales, as the name suggests, have teeth – but they don’t use them for chewing! Instead, they use them to grab large prey, such as salmon, and then swallow it whole. Baleen whales, on the other hand, have baleen plates. Baleen is made of keratin (just like your fingernails), which acts as a sieve when a whale takes a big gulp of water, then pushes it out through the baleen, catching tiny prey.

For example, humpback whales can travel over 10,000 kilometres every year between their feeding and birthing grounds!
Cetaceans use sound to navigate the ocean, find food and communicate with one another. In fact, some groups of cetaceans have different dialects, and some even have a series of clicks and whistles unique to each individual. This can be thought of as their name, which they use to identify themselves to others!
9. Cetaceans play an important role in the food web by keeping the ocean ecosystem balanced and healthy.
How? With their poop! As whales swim long distances through the ocean, diving deep down and then resurfacing, they mix nutrients in the ocean, with their poop acting as a fertilizer for phytoplankton. Phytoplankton are tiny plants in the ocean that pull carbon from the atmosphere while producing oxygen. In fact, phytoplankton produce 50 to 85 per cent of the oxygen we breathe, meaning every breath we take contains oxygen produced by the ocean!
Unfortunately, many cetaceans are threatened or endangered around the world. With a growing human population, industrialization of our oceans is also increasing. With more commercial fishing, shipping, and oil and gas exploration than ever, threats to cetaceans are increasing as well. Find out more about what we are doing to help conserve these remarkable animals and what you can do to help!
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