An Introduction to Whale Species: A Full Analysis of the Main Differences Between Baleen Whales and Toothed Whales

Whales are mammals that live in the ocean, breathing with lungs, giving birth to live young and nursing them, and maintaining a constant body temperature, which makes them fundamentally different from fish. Although the word "fish" appears in their name, whales are more closely related to cattle and sheep on land, and their ancestors originally came from land.

In terms of classification, whale species are broadly divided into two major groups: baleen whales and toothed whales. Baleen whales have comb-like baleen in their mouths and swallow krill, small fish and other food by filter feeding; the blue whale, humpback whale and fin whale all belong to this group. Toothed whales, by contrast, have teeth and actively hunt prey such as fish and squid; the sperm whale, killer whale and beluga are representatives of this group, and the dolphins we are familiar with also belong to the toothed whale family in terms of classification.

Different species of whales differ noticeably in body size and habits. The blue whale is considered the largest animal currently living on Earth, the humpback whale is known for its melodious songs and its behaviour of leaping out of the water, and the sperm whale is skilled at deep diving and can forage in relatively deep waters.

Because of the impact of whaling activities in history, the populations of many whale species have declined markedly; today most species have been included in protected categories, and commercial whaling is also strictly restricted. Ship strikes, ocean noise and entanglement in fishing nets are likewise threats that whales face. Understanding whale species helps us better know and protect these giants of the ocean.