If you think the largest fish in the ocean is the blue whale, you're wrong, it's the largest fish species!
When it comes to the largest creatures in the sea, many people will immediately think of whales, and the blue whale is the one most easily thought of, as it is the largest animal currently alive on Earth and the largest animal in terms of volume in the Earth's oceans. Its length can reach up to 33 meters and its weight can reach more than 180 tons, about 30 times that of a fully grown elephant and more than 3 times that of an M1A1 tank.
However, it is worth noting that blue whales belong to the baleen whale suborder and the baleen family, and are mammals, not fish! And whales have a physical structure and lifestyle that are obviously different from any mammalian group, so they have long been listed as a separate category. Their ancestors and evolutionary history were once disputed, but with the continuous progress of relevant research, it has now been fully confirmed that whales evolved from 50 million years ago from terrestrial odd-toed ungulates entering the water. DNA sequencing shows that whales are sister groups with hippos, and the branch formed by the two is also a sister group with ruminant suborders.
Although the 'whale' in its name is composed of the fish radical and resembles a fish in its appearance, like other baleen whales, blue whales mainly feed on small crustaceans (such as krill) and small fish, sometimes including squid. Blue whales usually need to forage in waters deeper than 100 meters during the day, and can forage at the surface at night. Blue whales begin to mate in late autumn and continue until the end of winter. Female whales usually produce one offspring every 2-3 years, and after a gestation period of 10-12 months, they generally give birth to calves in early winter. They are distributed in all four oceans.
In the ocean, there are many large creatures, such as a fish whose name contains 'whale'. It is the largest fish in the ocean, the whale shark.
The whale shark is a soft-rayed fish of the whale shark family and the whale shark suborder. Its length can reach 20 meters or more, and its weight is about 12.5 tons. The whale shark is the largest shark currently alive and the largest fish in the ocean and even the entire Earth.
Whale sharks are active filter feeders that attack plankton or fish using their sense of smell. Whale sharks don't need to swim forward to feed; they are often observed swaying up and down to suck in seawater and expel it to obtain food. This is the opposite of the whale shark, and they are gentle filter feeders who do not suck in seawater, but swim to make seawater pass through their gills.
Although the whale shark is very large and has a wide mouth of 1.5 meters, it is actually docile and does not have sharp teeth. It only eats plankton, algae and krill, small squids, etc. Like whales, it belongs to a filter-feeding animal. Therefore, compared to aggressive predators who need to travel long distances to track prey, the whale shark seems to be able to fill its stomach just by 'waiting for prey'.
Because whale sharks also have the characteristic of sensitive shark sense of smell, they can lock food targets through their sense of smell, then open their mouths to suck in seawater and expel it, through the opening and closing of their mouths, food will be blocked between the gill slits and swallowed, without spending too much energy. This is probably why whale sharks can grow to such a large size by eating such a small food item.
Each whale shark's spot is unique, biologists can use it to identify different individuals, so it is possible to accurately judge the number of whale sharks. It is common in the South China Sea, Taiwan Strait, East China Sea and South of the Yellow Sea. Although the whale shark is usually found in near-shore areas, its seasonal feeding activities occasionally occur in several coastal areas. The Philippines is the area with the highest density of whale shark distribution in the world.
However, when it comes to the largest fish that ever existed on Earth, it must be the giant shark. The giant shark lived in the ocean about 150 million years ago to 2.6 million years ago. Its length could reach 20 meters or more, and its weight was about 70 tons, and its biting force was as much as 20 tons, which was the top predator in the ocean during its survival period. However, this is a matter of the distant past, and currently, the largest creature in the ocean is the blue whale, and the largest fish is the whale shark!
