African elephants are known for their expressive facial features and dexterous trunks which can grasp even small objects with their pincer-like grip.

Now scientists have uncovered the secret of their adroitness. 

The species has the highest number of facial neurons of any land-dwelling mammal, allowing them to expertly flick their ears and perform intricate manoeuvres with their trunks. 

Facial neurons create a pathway from the brain to muscles and, in humans, allow for expressions such as smiling, frowning or raising the eyebrows. The more that are present, the more control an animal has over its facial musculature. 

Yet humans have only around 9,000 facial neurons compared with African elephants which have around 63,000. 

Experts believe these tens of thousands of extra facial brain cells are responsible for the extreme feats of trunk, ear and lip dexterity exhibited by African elephants. The animals are capable of plucking out a single blade of grass.

Researchers even think they have found the part of the brain responsible for their skilful pinching movement that allows the elephants to pick up objects - a cluster of very large brain cells which lie at one end of a group of neurons controlling the trunk muscles. 

High-density cell regions in the brain

Professor Michael Brecht, of the Berlin School of Mind and Brain, at Humboldt University and Leibniz Institute for Zoo and Wildlife Research said: “We see high-density cell regions in the brains of African elephants, which seem to represent their ‘trunk-fingers’.

“In African elephants these trunk fingers are very skilful because they pinch objects with them.

“We think elephants have such giant neurons because these cells need to extend very long cables to reach the trunk tip.”

The discovery was made by comparing the brains of eight African and Asian elephants from German zoos.

The project has taken more than a decade because the team had to wait for the animals to die before they could study the anatomy of the brain. 

The researchers found that Asian elephants had far fewer facial neurons than their African counterparts - around 54,000 - which seemed to be linked to less control of their trunks and ears. 

Asian elephants have smaller ears and do not have finger-like tips on the end of their trunks, meaning they must wrap their entire trunk around an object to pick it up. 

They believe the extra neurons in African elephants show that their brains and trunks evolved together, allowing for greater dexterity. 

Elephant trunks are also super sensitive to smells and can detect vibrations as well as having the strength to push down trees. 

The team found that dolphins are the only mammals which have more facial neurons, although researchers are unsure if they are needed.

Prof Brecht added: “I wonder if this large number of facial nucleus neurons are involved in vocalisation control (which is very complex in dolphins).

“I don’t think they use these neurons for facial gesturing, which is seemingly not so complex in dolphins.”

The research was published in the journal Science Advances.