Most mammals respond to the demands of exercise in the same way by breaking carbohydrates and stored lipids (fat) in their body, which releases the energy required to work them.
But every good rule deserves an exception. Vampire bats, for example, feed only on blood: an energy drink lipid and carbohydrates, and rich in protein. This realization inspired Giulia Rossi and Kenneth Welch at the University of Toronto to question how these animals were able to maintain energetic activities like flying. There was a possibility that bats were turning blood into carbohydrates which were being burnt then. But DRS Rossi and Welch were happy to entertain the hypothesis of a forest: that bats, instead, may be able to feed the protein in the way some bloodshed insects.
Tsetse flies and female mosquitoes fuel their energetically expensive flight activities by burning the amino acids that make proteins found in their food. This is an extraordinary metabolic trick that only these insects were mastered. To find out if the vampires were also performing bats, DRS Rossi, Welch and their fellow stakeholders went to the vampire-shikar.
Researchers traveled to a tropical forest in Belize, capturing 24 adult vampires and then withdrawn them to a nearby laboratory. Their goal was to feed the blood of bats, to exercise them and then monitor their breath for the chemical signs of metabolic processes in the game. Putting bats in wind tunnels where they could have monitored their breath because they flew were very challenging. Instead, DRS Rossi and Welch used the fact that Vampire bats are truly very good runners and have created a customized bat treadmill.
To do the work that the bats were getting their energy, the animals were consumed about eight minutes before the animals were placed in the center of the treadmill chamber. Most of the bats consumed blood, with two amino acids (either leucine or glycine), chemically already labeled. All three were kept as control and blood -soaked blood was fed.
Researchers reported biologyThe breath that included chemical labels in breathing. This means that bats were using amino acids from the blood that they recently eaten as their primary source of fuel as soon as they started exercise. If they were burning lipids and carbohydrates, as all other mammals do, their breathing was label-free.
These findings suggest that vampires bats and blood-feeding insects have metabolic systems which are very similar. From a evolutionary point of view, it is impossible that they developed into insects and then maintained by bats without appearing in other mutual relatives. It is very likely that natural selection led both groups of animals to develop a solution to the same problem.
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