Let 'Em Eat Mud
Pregnant rain forest bats like to lick mud, probably to make sure they get enough minerals in their diets. Some people do too. Chelsea Wald reports.
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It's often joked that pregnant women crave pickles and ice cream; well, it seems that pregnant Ecuadorian bats crave salty mud. The soil in the rainforests where these bats live is notoriously poor in minerals. But muddy spots called “mineral licks” are rare exceptions. A team of scientists from Boston and Berlin trapped bats throughout the Ecuadorian rainforest, including at these mineral licks. They found that bats at the licks were overwhelmingly female, and pregnant or nursing.
The bats were probably there to lap up the mud. The researchers think the bats need the minerals to pass on to their young for their growing bones. Fruit-eating bats were more likely to visit the mineral licks than their insect-eating cousins, who get some minerals from their food. Other animals and indigenous people also square their diets with these minerally muds. In fact, they’re sold in Amazonian markets. Writing in the journal “Research Letters in Ecology,” the authors say their muddy discovery could help explain how rainforests can spawn such rich biodiversity with such poor soil.
—Chelsea Wald
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