Are Bats Old Rats?
WouterThere’s an old saying that says bats are old rats, but it’s not true. Scientists have discovered that bats have the same genetic makeup as a human. Specifically, they have similar physiology, but bats are different from humans in several ways. First, they have brown fat, which has a lot of mitochondria. These are organelles in the cell that perform most of the body’s metabolic processes, including production of heat. Moreover, brown fat cells are activated by reduced temperatures. This helps them raise their body temperature slowly, up to 37 degrees Celsius.
Secondly, bats are the only mammals that have wings that are powered by flapping motion. This is in contrast to the way that other mammals glide on expanded membranes. Scientists believe that bats evolved this method and later evolved wings, which have a large number of bones. However, this theory is controversial.
Third, bats’ lifespans are longer than those of mice. For example, they live for nearly 30 years as compared to just four years in house mice. In addition, they have better health than mice do, with their livers accumulating fewer damaged proteins as they age. Moreover, cave and Brazilian free-tailed bats can live up to 12 years.
Scientists have also found that bats’ fingers are shorter than the fingers of mice. This suggests that the difference between these two species is due to the expression of a gene that controls Bmp signaling. Therefore, researchers believe that bats have a higher Bmp2 activity than mice. If this hypothesis is correct, they will have to observe changes in regulatory RNAs, epigenetic controls, and DNA sequences surrounding the Bmp2 gene.
