Extreme suction helps elephants suck up water quickly, and to hold water and food in their trunks. Extreme suction enables elephants to inhale water at speeds nearly 30 times faster than humans exhale air during a sneeze.
New Scientist magazine, on 2 June 2021, announced recent research results on the effectiveness of elephants using extreme suction. Elephants use their trunks, which weigh more than 100 kilograms (220 pounds), in a variety of ways: to forage through vegetation for food, to drink, and even as a snorkel when wading through deep water.
To better understand the trunk in action, scientist Andrew Schulz at the Georgia Institute of Technology in America, and his colleagues, filmed a 34-year-old female African Savannah Elephant (Loxodonta africana) while she completed a series of tests at a zoo in Atlanta.
The scientific researchers filled an aquarium with water and measured how long the elephant spent inhaling water from the tank through its trunk. They measured the volume of water left in the aquarium after the experiment. Schulz and his team also estimated the trunk’s capacity by measuring the internal volume of a trunk that came from another 38-year-old African Elephant.
The researchers calculated that elephants suck up water with what would be an equivalent air velocity of 150 metres per second. “That is around 30 times the speed of the human sneeze,” said Schulz. When humans sneeze, they exhale air with a velocity of 4.5 metres per second.
The researchers used ultrasound imaging to view the inside of the trunk as the elephant inhaled. They found that the elephant was able to dilate its nostrils by 30%, increasing the volume of nasal cavity by 64%.
“They use this mechanism to suction water and also store it in the trunk to spray on their body to cool down,” said Schulz. “This is a behaviour that few vertebrate animals other than fish use,” said John Hutchinson at the Royal Veterinary College in London.
Journal reference: Journal of the Royal Society Interface, DOI: 10.1098/rsif.2021.0215