Elephants are fascinating animals. Despite such fascination, our knowledge of the elephant brain is limited, and neuroanatomical differences between Asian (Elephas maximus) and African elephants (Loxodonta africana) are largely unexplored. In the new study, scientists from the Humboldt-Universität zu Berlin and the Leibniz Institute for Zoo and Wildlife Research collected a large number of elephant brains and studied their macro-anatomy to characterize species differences. To their surprise, the authors found that Asian elephants have larger brains and larger gray-matter volume than African elephants, and this brain size difference contrasts with the smaller bodies of Asian elephants.
Asian elephants in Myanmar. Image credit: John Jackson.
“Morphological differences between elephant species are widely known,” said first author Dr. Malav Shah from the Humboldt-Universität zu Berlin and colleagues.
“For example, African savanna elephants are larger and have larger ears compared with Asian elephants.”
“Only African elephant cows are known to develop large tusks compared with rudimentary tusks in Asian cows.”
“These differences reflect the substantial genetic separation of Asian and African savanna elephants, which is suggested to date back 5-8 million years.”
In the study, the researchers analyzed the weight and structure of the brains of Asian elephants and African elephants based on dissections of wild and zoo animals as well as on literature data and MRI scans.
They showed that adult female Asian elephants have significantly heavier brains, weighing a good 5,300 grams on average, than their African counterparts, which average just over 4,400 grams.
This finding could not be conclusively confirmed for male elephants — which have significantly heavier brains in both species — owing to the limited data available on Asian elephants.
However, the cerebellum is proportionally heavier in African elephants (22% of the total brain weight) than in Asian elephants (19%).
The scientists were also able to show that elephants exhibit very large postnatal brain growth.
The brains of adult elephants are about three times as heavy as they were at birth.
This means that elephants have a significantly higher lifetime brain growth than all primates — with the exception of humans, in which the brain at birth weighs only around a fifth of its final weight.
Juvenile African elephants in Kenya. Image credit: George Wittemyer.
“The difference in brain weight is perhaps the most important difference between these two elephant species,” Dr. Shah said.
“It could explain important behavioral differences between Asian and African elephants.”
“For example, both species show very different behavior when interacting with humans.”
“Asian elephants have been partially domesticated over thousands of years and are used as work animals in different cultures and regions.”
“In the case of African elephants, there are only very few cases in which domestication was even partially successful.”
“It is much more difficult to habituate African elephants to human company than Asian elephants.”
The study was published today in the journal PNAS Nexus.
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Malav Shah et al. 2025. Larger brains and relatively smaller cerebella in Asian elephants compared with African savanna elephants. PNAS Nexus 4 (5): pgaf141; doi: 10.1093/pnasnexus/pgaf141
