Wild elephants might only need 2 hours of sleep a night

It seems wild elephants don't need a full eight hours of sleep every night to maintain one of the longest memories in the animal kingdom.

According to one team of scientists in South Africa, wild elephants sleep an average of just two hours a night — that's less than any other animal on record.

That's surprising because elephants are known for their incredible memories. And studies have shown that sleep and memory are connected.

The scientists used a tool similar to a Fitbit to track the elephants' movement. They attached the devices to the animals' trunks, which are almost constantly in motion. When an elephant's trunk was still for more than five minutes, the team determined the mammal was asleep.

The team also found the pair of wild African elephants it tested slept in bursts. They slept both lying down and standing up. And sometimes, they didn't sleep at all.

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Adorable elephants
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Adorable elephants
An Asian elephant beats the heat by gathering water from a sprinkler with his trunk, at Berlin's Zoologischer Garten Zoo August 10, 2015 as temperatures rose past the 30 degree mark.. (Photo credit: JOHN MACDOUGALL/AFP/Getty Images)
In this photo taken on July 24, 2015, Sri Lankan elephants bathes in a lake at Yala National Park in the southern district of Yala, some 250kms southwest of Colombo. Yala National Park is the most visited and second largest national park in Sri Lanka. (Photo credit:  Ishara S.KODIKARA/AFP/Getty Images)
MELBOURNE, AUSTRALIA - JULY 15: Nick Riewoldt of the Saints and Jack Riewoldt of the Tigers meet elephant Bong Su, the largest animal in Australia during an AFL media opportunity at Melbourne Zoo on July 15, 2015 in Melbourne, Australia. (Photo by Robert Cianflone/Getty Images)
An elephant cools off on a hot summer day at Madrid's zoo on July 2, 2015. Spain is heading for a new heatwave which will last for at least nine days and extend to the rest of Europe, the national weather office said on July 1. (Photo credit: DANI POZO/AFP/Getty Images)
IZMIR, TURKEY - JUNE 26: Deniz, the baby elephant living at Izmir Wild Life Park, looks at an inflatable pool brought for it in Izmir, Turkey on June 26, 2015. (Photo by Izmir Metropolitan Municipality/Anadolu Agency/Getty Images)
Baby elephants play in water at the Israeli zoo of Ramat Gan, north of the Mediterranean coastal city of Tel Aviv, on May 27, 2015 as temperatures reached 44 degrees Celsius (111 Fahrenheit). (Photo credit: JACK GUEZ/AFP/Getty Images)
A male elephant charges towards unseen Indian villagers after they threw stones in an attempt to scare away a herd of wild elephants which strayed close to the village of Kolabari, some 50kms from Siliguri close to the India-Nepal border on May 25, 2015. Indian forest guards and local villagers used firecrackers to scare away the elephants after sightings caused unease among villagers. Human-elephant conflicts are on the rise in India as villagers and farmers encroach on the elephants' natural habitat.  (Photo credit: DIPTENDU DUTTA/AFP/Getty Images)
This picture taken on May 21, 2015 shows an elephant at the Lewa Wildlife Conservancy at the foot of Mount Kenya, approximately 300 km north of the capital Nairobi. An estimated 470,000 wild elephants remain in Africa, according to a count by the NGO Elephants Without Borders, down from several million a century ago. (Photo credit: TONY KARUMBA/AFP/Getty Images)
PINNAWALA, SRI LANKA - APRIL 16: Elephants are seen at Pinnawala Elephant Orphanage in Sri Lanka, on April 16, 2015. Pinnawala Elephant Orphanage is an orphanage, nursery and captive breeding ground for wild Asian elephants located at Pinnawala village, northwest of Kegalle town in Sabaragamuwa Province of Sri Lanka. Pinnawala is notable for having the largest herd of captive elephants in the world. The orphanage was originally founded in order to afford care and protection to many of the orphaned unweaned wild elephants found wandering in and near the forests of Sri Lanka. It was established in 1975 by the Sri Lanka Department of Wildlife Conservation (DWC). (Photo by Fatih Dogan/Anadolu Agency/Getty Images)
SYDNEY, AUSTRALIA - APRIL 10: Elephants feed on giant pumpkins at Taronga Zoo on April 10, 2015 in Sydney, Australia. Taronga Zoo and the Sydney Royal Easter Show partnered together to recycle the giant pumpkins, including one pumpkin weighing in at 728kg. (Photo by Cameron Spencer/Getty Images)
An elephant splashes at sunset in the waters of the Chobe river in Botswana Chobe National Park, in the north eastern of the country on March 20, 2015. African elephants could be extinct in the wild within a few decades, experts warned on March 23, 2015 at a major conservation summit in Botswana that highlighted an alarming decline in numbers due to poaching. (Photo credit: CHRIS JEK/AFP/Getty Images)
Bayanga, Central African Republic - March 15: An African forest elephant (Loxodonta cyclotis) at Dzanga Bai Saline in Dzanga National Park at triangle of Democratic Republic of the Congo, Cameroon and Central African Republic on March 13, 2015 in Bayanga, Central African Republic. (Photo by Michael Gottschalk/Photothek via Getty Images)
Bayanga, Central African Republic - March 15: An African forest elephant (Loxodonta cyclotis) at Dzanga Bai Saline in Dzanga National Park at triangle of Democratic Republic of the Congo, Cameroon and Central African Republic on March 13, 2015 in Bayanga, Central African Republic. (Photo by Michael Gottschalk/Photothek via Getty Images)
Elephant Asha (front), father Assam (C) and mother Angele (L) are pictured on Asha's 2nd birthday in the zoo and Botanic Garden in Budapest on February 14, 2015.  (Photo credit: ATTILA KISBENEDEK/AFP/Getty Images)
This picture taken on January 31, 2015, shows Tang Gwaa of the Thai blind orchestra playing with an elephant after a rehearsal ahead of a concert at the Thai Elephants Research and Conservation Fund in Khao Yai national park 180 km (112 miles) north east of Bangkok. Deftly feeling their way along the bumps of the braille score, the young players of Thailand's first blind orchestra memorize scales, defying both their impairment and ingrained negative attitudes towards disability. (Photo credit: NICOLAS ASFOURI/AFP/Getty Images)
IZMIR, TURKEY - NOVEMBER 07: Baby elephant named Deniz, which has been kept in a sanctuary since she was born due to the risk of getting infection, is seen with her sister Izmr on her first day outside of the sanctuary at Wildlife Park of Izmir, Turkey on November 07, 2014. (Photo by Izmir Metropolitan Municipality/Anadolu Agency/Getty Images)
Female elephants Safari (L) and Chupa walk in their enclosure on October 8, 2014 in a zoo in Erfurt, Germany. (Photo credit: MARTIN SCHUTT/AFP/Getty Images)
NEW DELHI, INDIA - AUGUST 30: Elephants roaming at Yamuna river bank, on August 30, 2014 in New Delhi, India. These elephants belong to several individual owners who work the elephants to earn a living for themselves and their families. (Photo by Mohd Zakir/Hindustan Times via Getty Images)
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SEE MORE: Protected Land Isn't Keeping African Forest Elephants Safe

Sleep experts are taking the study into account, but others say it's possible wild elephants have evolved to thrive with little or no sleep. The enormous mammals are busy eating 17 to 18 hours each day.

In spite of the small sample size — just two female elephants — the scientists are confident the results represent most wild elephants. But more research needs to be done to confirm the study's accuracy.

RELATED: Learn more about elephant conservation efforts:

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Elephant conservation in Malaysia
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Elephant conservation in Malaysia
KUALA GANDAH, MALAYSIA - MARCH 01: An Elephant is seen swimming in a river near the National Elephant Conservation Centre on March 1, 2016 in Kuala Gandah, Malaysia. Almost 1,200 wild Asian Elephants, also known as Elephus Maximus, are left in Malaysia and this is the only conservation centre set up to relocate these displaced pachyderms. The elephants here have been rescued from all over Peninsula Malaysia, providing them a safe sanctuary in the wild, according to World Wildlife Foundation, the increasing human population in Asia has affected the elephant's dense, but diminishing forest habitat. (Photo by Mohd Samsul Mohd Said/Getty Images)
KUALA GANDAH, MALAYSIA - MARCH 01: Foreign tourists are seen bathing with an elephant in a river near the National Elephant Conservation Centre on March 1, 2016 in Kuala Gandah, Malaysia. Almost 1,200 wild Asian Elephants, also known as Elephus Maximus, are left in Malaysia and this is the only conservation centre set up to relocate these displaced pachyderms. The elephants here have been rescued from all over Peninsula Malaysia, providing them a safe sanctuary in the wild, according to World Wildlife Foundation, the increasing human population in Asia has affected the elephant's dense, but diminishing forest habitat. (Photo by Mohd Samsul Mohd Said/Getty Images)
KUALA GANDAH, MALAYSIA - MARCH 01: A Nature guide is seen walking with an elephant after bathing and cleaning in a river near the National Elephant Conservation Centre on March 1, 2016 in Kuala Gandah, Malaysia. Almost 1,200 wild Asian Elephants, also known as Elephus Maximus, are left in Malaysia and this is the only conservation centre set up to relocate these displaced pachyderms. The elephants here have been rescued from all over Peninsula Malaysia, providing them a safe sanctuary in the wild, according to World Wildlife Foundation, the increasing human population in Asia has affected the elephant's dense, but diminishing forest habitat. (Photo by Mohd Samsul Mohd Said/Getty Images)
KUALA GANDAH, MALAYSIA - MARCH 01: Nature guides bath elephant's in a river near the National Elephant Conservation Centre on March 1, 2016 in Kuala Gandah, Malaysia. Almost 1,200 wild Asian Elephants, also known as Elephus Maximus, are left in Malaysia and this is the only conservation centre set up to relocate these displaced pachyderms. The elephants here have been rescued from all over Peninsula Malaysia, providing them a safe sanctuary in the wild, according to World Wildlife Foundation, the increasing human population in Asia has affected the elephant's dense, but diminishing forest habitat. (Photo by Mohd Samsul Mohd Said/Getty Images)
KUALA GANDAH, MALAYSIA - MARCH 01: A Nature guide is seen with an elephant in a river near the National Elephant Conservation Centre on March 1, 2016 in Kuala Gandah, Malaysia. Almost 1,200 wild Asian Elephants, also known as Elephus Maximus, are left in Malaysia and this is the only conservation centre set up to relocate these displaced pachyderms. The elephants here have been rescued from all over Peninsula Malaysia, providing them a safe sanctuary in the wild, according to World Wildlife Foundation, the increasing human population in Asia has affected the elephant's dense, but diminishing forest habitat. (Photo by Mohd Samsul Mohd Said/Getty Images)
KUALA GANDAH, MALAYSIA - MARCH 01: A Nature guide rides an elephant in a river near the National Elephant Conservation Centre on March 1, 2016 in Kuala Gandah, Malaysia. Almost 1,200 wild Asian Elephants, also known as Elephus Maximus, are left in Malaysia and this is the only conservation centre set up to relocate these displaced pachyderms. The elephants here have been rescued from all over Peninsula Malaysia, providing them a safe sanctuary in the wild, according to World Wildlife Foundation, the increasing human population in Asia has affected the elephant's dense, but diminishing forest habitat. (Photo by Mohd Samsul Mohd Said/Getty Images)
This picture taken on November 10, 2015 shows mahouts with their elephants in a river at the Kuala Gandah Elephant Conservation Centre in Kuala Gandah, Malaysia's Pahang state. The conservation centre is a base for the Elephant Relocation Team, which began the elephant translocation programme in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
This picture taken on November 10, 2015 shows a mahout riding an elephant along a river at the Kuala Gandah Elephant Conservation Centre in Kuala Gandah, Malaysia's Pahang state. The conservation centre is a base for the Elephant Relocation Team, which began the elephant translocation programme in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
This picture taken on November 10, 2015 shows visitors looking on as mahouts lead their elephants from a river after washing them at the Kuala Gandah Elephant Conservation Centre in Kuala Gandah, Malaysia's Pahang state. The conservation centre is a base for the Elephant Relocation Team, which began the elephant translocation programme in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
This picture taken on November 10, 2015 shows mahouts riding elephants along a river at the Kuala Gandah Elephant Conservation Centre in Kuala Gandah, Malaysia's Pahang state. The conservation centre is a base for the Elephant Relocation Team, which began the elephant translocation programme in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
A foreign visitor feeds an elephant at the Kuala Gandah Elephant Conservation Center in Kuala Gandah, Pahang, on the outside Kuala Lumpur on June 16, 2013. The conservation center is a base for the Elephant Relocation Team, which began the elephant translocation program in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
Visitors play with an elephant in the river at the Kuala Gandah Elephant Conservation Center in Kuala Gandah, Pahang, on the outside Kuala Lumpur on June 16, 2013. The conservation center is a base for the Elephant Relocation Team, which began the elephant translocation program in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
Keepers lead the elephants out of the river after cleaning them at the Kuala Gandah Elephant Conservation Center in Kuala Gandah, Pahang, on the outside Kuala Lumpur on June 16, 2013. The conservation center is a base for the Elephant Relocation Team, which began the elephant translocation program in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
A Keeper rides an elephant in the river at the Kuala Gandah Elephant Conservation Center in Kuala Gandah, Pahang, on the outside Kuala Lumpur on June 16, 2013. The conservation center is a base for the Elephant Relocation Team, which began the elephant translocation program in 1974. AFP PHOTO / MOHD RASFAN (Photo credit should read MOHD RASFAN/AFP/Getty Images)
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