Dr Gingerich believes that primitive whales lived on land by hunting other animals and fish. Later, due to the attraction of a large number of fish, they gradually moved to the sea. And more importantly, whale fossils. well preserved and exactly the same as that of terrestrial mammals.
The skeletal system of modern whales can support the fact that whales entered the ocean from land during their long historical journey. Modern whales have well-developed skulls, small brains, large faces, extremely narrow frontal bones, and a wingspan on both left and right sides. The premaxilla and maxilla are greatly extended to form a longer snout, and the mandible is adapted to the snout. . The clavicle is absent from the bones of the shoulder girdle of the fins, the shoulder blades are broad and fan-shaped, the humerus is considerably shortshortened and the radius and ulna are flat. It has five fingers, but the first and fifth fingers are shortened leaving only traces, and the second and third fingers are very long, especially the second finger is the longest.
From the skeletal system diagram, we can see that the whale's forelimbs have five fingers and hind limb bones. It can be seen that whales lived on land in prehistoric times and crawled on all fours. ocean, they To adapt to swimming life in the ocean, the front limbs became thin and flat fins, and the hind limbs degenerated and left no trace outside the body. The degenerated hind limbs ossified into a very small arched bone, which was completely separated. vertebrae and buried under the skin. The dorsal fin may or may not be present, and the caudal fin has no bones and is composed of connective tissue and graisse. The caudal fin is flattened into left and right wings and becomes the main swimming organ. It can be inferred that the fact that the whales entered the ocean from land during their long historical journey
This is because the scope of the aquarium is still too small for the blue whale, allowing it to survive in such a place may not be a good thing for its growth, so this approach is also very unrealistic. The scope of the aquarium is limited. Imprisoning such a huge creature there will completely lose its freedom, so it is even more suitable for the aquarium. Wed.