Surviving on blood alone is not a picnic. But some genetic tweaks may have helped vampire bats evolve into the only mammal known to feed exclusively on vampire bats.
These bats have developed a range of physiological and behavioral strategies to feed on blood alone. However, the genetic map behind this bloodthirsty behavior remains obscure.but Bats appear to have lost 13 genes Researchers on March 25 at scientific progress.
“Sometimes losing genes over evolutionary timescales can actually be adaptive or beneficial,” says Michael Shearer, a genomics scientist now at the Senckenberg Association for Nature Research in Frankfurt.
Shearer and his colleagues pieced together a genetic guide for the common vampire bat (Arrowroot) and compared it with the genomes of 26 other bat species, including six in the same family as vampire bats.Then the research team D. round They are either lost entirely or inactivated by mutation.
Of the 13 missing genes, Three previously reported in vampire batsThese genes are associated with sweet and bitter taste receptors in other animals, which means vampire bats may have a diminished sense of taste — and drink blood better. The other 10 missing genes were newly discovered in bats, and the researchers raised some ideas about how the loss of these genes could support a blood-rich diet.
Some genes help increase insulin levels in the body and convert ingested sugar into a form that can be stored. Given the low sugar levels in the blood, this processing and storage system may be less active in vampire bats, and the genes may not be as useful anymore. In other mammals, another gene is involved in stomach acid production, which helps break down solid food. The gene may have been lost as vampire bat stomachs evolved to primarily store and absorb fluids.
One of the other missing genes inhibited iron absorption in gastrointestinal cells. Blood is low in calories but rich in iron. Vampire bats must drink up to 1.4 times their body weight in water during each feeding, and ingest potentially harmful amounts of iron in the process. Gastrointestinal cells in the guts of vampire bats shed regularly, so by losing this gene, bats may absorb large amounts of iron and excrete it quickly to avoid overload — an idea supported by previous research.
A missing gene may even be involved in the extraordinary cognitive abilities of vampire bats, the researchers believe.Because bats are prone to starvation, they share refluxed blood and Bats are more likely to do this previously donated to myself (SN: November 19, 2015).Vampire bats also form long-term bonds even feeding with their friends in the wild (SN: 10/31/2019; SN: 9/23/21). In other animals, the gene is involved in breaking down compounds produced by nerve cells that are involved in learning and memory — traits thought to be necessary for vampire bat social skills.
“I think there are some compelling hypotheses out there,” said David Lieberus, an evolutionary genomics scientist at Temple University in Philadelphia who was not involved in the study.He said it would be interesting to see if the other two vampire bats also lost these genes, since they feed more on bird blood, while D. round Prefers to be absorbed from mammals.
Whether diet caused these changes, or vice versa, is unclear. Either way, it could be a gradual process over millions of years, Shearer said. “Maybe they start drinking more and more blood, and then you have time to better adjust to this extremely challenging diet.”