Similar to Humans, Elephants also Vary What They Eat for Dinner Every Night
Published:03 Aug.2023 Source:Brown University
Elephants eat plants. That's common knowledge to biologists and animal-loving schoolchildren alike. Yet figuring out exactly what kind of plants the iconic herbivores eat is more complicated. A new study from a global team that included Brown conservation biologists used innovative methods to efficiently and precisely analyze the dietary habits of two groups of elephants in Kenya, down to the specific types of plants eaten by which animals in the group. Their findings on the habits of individual elephants help answer important questions about the foraging behaviors of groups, and aid biologists in understanding the conservation approaches that best keep elephants not only sated but satisfied.
The research group compared the new genetic technique to a method called stable isotope analysis, which involves a chemical analysis of animal hair. Two of the study authors, George Wittemyer at Colorado State University and Thure Cerling at the University of Utah, had previously shown that elephants switch from eating fresh grasses when it rains to eating trees during the long dry season. While this advanced study by allowing researchers to identify broad-scale dietary patterns, they still couldn't discern the different types of plants in the elephant's diet. The team coupled combined analyses of carbon stable isotopes from the feces and hair of elephants with dietary DNA metabarcoding, GPS-tracking and remote-sensing data to evaluate the dietary variation of individual elephants in two groups.
While the study wasn't designed to explain social behavior, these findings help inform theories of why a group of elephants may forage together: The individual elephants don't always eat exactly the same plants at the same time, so there will usually be enough plants to go around. These findings may offer valuable insights for conservation biologists. To protect elephants and other major species and create environments in which they can successfully reproduce and grow their populations, they need a variety of plants to eat. This may also decrease the chances of inter-species competition and prevent the animals from poaching human food sources, such as crops.