News Release

Elephants' quantitative ability may be rooted in olfaction

Peer-Reviewed Publication

Proceedings of the National Academy of Sciences

An Elephant (Or Elephants) at the Golden Triangle Asian Elephant Foundation in Chiang Rai, Thailand

image: The elephant trunk contains tens of thousands of muscles and acts as an exceptional olfactory tool by which elephants can find food and distinguish between differences in quantity. Here, an elephant (or elephants) at the Golden Triangle Asian Elephant Foundation in Chiang Rai, Thailand. view more 

Credit: Image courtesy of Hoi-Lam Jim (Vetmeduni Vienna, Vienna, Austria).

A study finds that elephants can use their sense of smell to pick the greater of two quantities of food. Several nonhuman species, including some primates, cetaceans, birds, and elephants, can visually identify the greater of two quantities. Wild elephants, however, are thought to likely rely on their sense of smell, hearing, and touch to find water and food, using vision as a complementary sense. Joshua Plotnik and colleagues tested whether six 12-45-year-old Asian elephants (Elephas maximus) living on the grounds of a hotel in northern Thailand could distinguish between two quantities of food using only their sense of smell. The authors used a sliding table to present pairs of locked buckets containing 11 different ratios of sunflower seeds that the elephants could smell but not see. Subsequently, the buckets were unlocked, and the elephants chose one of the two buckets, slid open its lid, and consumed the seeds inside. Overall, the elephants chose the greater quantity of seeds in each pair, regardless of the actual quantity of seeds presented. As expected, the elephants' performance improved as the difference between the quantities of seeds in each pair increased and worsened as the ratio between the pair of presented quantities increased, reinforcing the notion that elephants have a nose for quantity. Additionally, the authors ruled out the possibility that the elephants were using a sense other than smell, acting on inadvertent cues from the experimenters, or responding to unrelated olfactory cues during trials. According to the authors, understanding how elephants use their sense of smell while foraging might help mitigate conflict in regions where elephant habitats and human settlements overlap, aiding conservation efforts.

###

Article #18-18284: "Elephants have a nose for quantity," by Joshua Plotnik et al.

MEDIA CONTACT: Joshua Plotnik, Hunter College, City University of New York, NY; tel: 646-210-6138; email: <Joshua.plotnik@gmail.com>


Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.