Explanation:
To swim, they move their tails up and down, rather than back and forth as fishes do. This is because whales evolved from walking land mammals whose backbones did not naturally bend side to side, but up and down. ... Whales do the same thing as they swim, showing their ancient terrestrial heritage.
Cetaceans are fully aquatic marine mammals belonging to the order Artiodactyla, and branched off from other artiodactyls around 50 mya (million years ago). Cetaceans are thought to have evolved during the Eocene or earlier, sharing a closest common ancestor with hippopotamuses.
Answer:
Genetics is a branch of science that deals with the study of genes, their sequence, function, variation, and heredity.
Increasing understanding of genetics help in making new fields of health care, for example,
- Gene therapy helps in treating various genetic diseases such as cystic fibrosis et cetera.
- Molecular genetics help in the development of more precise methods for diagnosis such as ELISA.
- Pedigree analysis and karyotypes help in early detection of possible hereditary diseases.
- DNA fingerprinting helps in detecting criminal suspects, paternity test, identification of dead organism et cetera.
Lions and tigers competing for an antelope.
The answer to this question would be: rapid impulse transmission.
By having organ near the head, the brain can process the information faster because the length of the nerve that carries the impulse from organ would be much shorter. The nerve also at lower risk of damage since it was shorter.
But it makes the head very important and damage to the head can cause much more problem than any part of the body.