Nectar feeding bats burn sugar faster than any other mammal on Earth

Nectar-feeding bats burn sugar faster than any other mammal on Earth - and three times faster than even top-class athletes - says a new study published online in the British Ecological Societys journal Functional Ecology.

Washington, Aug 6 : Nectar-feeding bats burn sugar faster than any other mammal on Earth - and three times faster than even top-class athletes - says a new study published online in the British Ecological Society's journal Functional Ecology.

As part of the study, the team of Dr Christian Voigt of the Leibniz Institute for Zoo and Wildlife Research in Berlin, Germany, and Professor John Speakman of the University of Aberdeen, Scotland, fed a captive breeding colony of bats in Germany, sugar labelled with non-radioactive carbon-13.

Then they measured the amount of carbon-13 in the bats' exhaled breath.

Findings revealed that these bats lived a highly energetic life, and were very vulnerable to any changes in their environment that interrupted their fuel supply for even a short period.

"We found that nectar-feeding bats made use of the sugar they were drinking for their metabolism within minutes after drinking it, and after less than half an hour they were fuelling 100 percent of their metabolism from this source. For comparison, the highest rates reported in humans are for athletes who can fuel up to 30 percent of their metabolism directly from power drinks," the researchers wrote in their study.

According to the scientists, the reason these bats live on such an energetic knife-edge is dependent on the food source they lived on and the way they get around.

The bats feed on floral nectars that contain simple sugars such as sucrose, glucose and fructose, which are produced in only very small amounts by flowering plants. The sugars are rapidly absorbed and digested, and by metabolising them directly - rather than converting them to fat or glycogen and then using them up later - the bats get the maximum energy they can from the sugars, the researchers say.

A second experiment that measured how fast the bats used their meagre fat stores revealed that the bats depleted almost 60 percent of their fat stores each day, but even this phenomenal rate was still barely enough to sustain their metabolism when nectar was absent.

"This underlines how accurately these bats must balance their energy requirements every day and how vulnerable they are to ecological perturbations that might interrupt their fuel supply for even a short period," the researchers said.

ANI