There are many amazing and mysterious creatures in the animal world. Some of the most interesting representatives of marine fauna are whales and dolphins. These mammals, which have fully adapted to aquatic environments, are a classic example of convergent evolution. In honor of World Whale and Dolphin Day, we’ve gathered six interesting facts about them for you.
1. Origin of cetaceans: from wolves to sea creatures
The oldest cetaceans were the pachycetes, which lived about 50 million years ago. These four-legged animals resembled wolves with an elongated face and did not exceed one meter in length. Pakicetes lived a semi-aquatic lifestyle, hunting for fish like seals and sea elephants. Interestingly, pachycetes had small hooves on their toes, and their closest relatives among non-cetacean species were hippopotamuses.
2. Primitive cetaceans: crocodile-like animals
Ambulocetes, representatives of primitive cetaceans, were a transitional form between land animals and full aquatic animals. Their body was narrow and streamlined, and their snout was elongated with high-set eyes. Ambulocetes probably hunted like crocodiles, ambushing large mammals and hiding underwater near the shore. At this stage of evolution, cetaceans had not yet lost the ability to go on land.
3. The unique communication of dolphins
Cetaceans communicate using sounds, and dolphins are among the most talkative members of this group of animals. Each individual responds to a specific type of whistle, which is set at birth and remains unchanged. Scientists have found that dolphins are able to memorize new sound signals throughout their lives. They can also memorize and respond to certain “names.” This ability helps them maintain communication in conditions of poor visibility underwater.
4. The melodic “songs” of whales
During the mating season, whales communicate with each other with complex melodic sounds similar to singing. Some of these “songs” become extremely popular and spread around the world. Interestingly, the chain of borrowings can transmit the song of humpback whales over a distance of many thousands of kilometers – from Polynesia to South America. Scientists have not yet been able to determine which themes become popular and on what principle they change.
5. Sperm whales and their “echo sounder”
Sperm whales, or giant whales, have a unique way of orienting themselves in space – an “echoloter”. They make specific sounds that are reflected off objects and return to the sperm whale. Thus, they can determine the distance to the object and its shape. Interestingly, for a long time scientists mistakenly considered this organ of the sperm whale to be a sperm sac.
6. History of cetacean research
The study of cetaceans began long before our time. Already in ancient times, people were interested in these mysterious creatures. The Greeks and Romans described whales and dolphins in their works. In the 19th century, active scientific work began to study these animals, and with the development of modern technology, scientists were able to obtain more accurate data on the behavior and physiology of cetaceans.
Whales and dolphins are amazing creatures of nature that continue to amaze researchers with their abilities and behavior. Their evolution and unique abilities pique the interest of scientists and animal lovers. They are not only a symbol of the sea, but also important elements of ecosystems, being at the top of the food chain.
