Evolution: a different view with loss of DNA segments (Introduction)

by David Turell , Sunday, March 27, 2022, 17:09 (971 days ago) @ David Turell

Vampire bats live on blood alone:

https://www.sciencenews.org/article/vampire-bat-lost-genes-blood-mammal

"Surviving on blood alone is no picnic. But a handful of genetic tweaks may have helped vampire bats evolve to become the only mammal known to feed exclusively on the stuff.

"These bats have developed a range of physiological and behavioral strategies to exist on a blood-only diet. The genetic picture behind this sanguivorous behavior, however, is still blurry. But 13 genes that the bats appear to have lost over time could underpin some of the behavior, researchers report March 25 in Science Advances.

“'Sometimes losing genes in evolutionary time frames can actually be adaptive or beneficial,” says Michael Hiller, a genomicist now at the Senckenberg Society for Nature Research in Frankfurt.

"Hiller and his colleagues pieced together the genetic instruction book of the common vampire bat (Desmodus rotundus) and compared it with the genomes of 26 other bat species, including six from the same family as vampire bats. The team then searched for genes in D. rotundus that had either been lost entirely or inactivated through mutations.

"Of the 13 missing genes, three had been previously reported in vampire bats. These genes are associated with sweet and bitter taste receptors in other animals, meaning vampire bats probably have a diminished sense of taste — all the better for drinking blood. The other 10 lost genes are newly identified in the bats, and the researchers propose several ideas about how the absence of these genes could support a blood-rich diet.

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"Whether the diet caused these changes, or vice versa, isn’t known. Either way, it was probably a gradual process over millions of years, Hiller says. “Maybe they started drinking more and more blood, and then you have time to better adapt to this very challenging diet.'”

Comment: pure Behe. Evolution advances with loss of genes.