News / Science & Technology

Study: Dolphins Remember Each Other for Decades

File - Dolphins are seen at the Brookfield Zoo in Brookfield, Ill. (AP Photo/Chicago Zoological Society, Jim Schulz)
File - Dolphins are seen at the Brookfield Zoo in Brookfield, Ill. (AP Photo/Chicago Zoological Society, Jim Schulz)
VOA News
Dolphins, not elephants, may have the best memories of any non-human species.

In a new study, scientists say dolphins in captivity have shown an ability to recognize former tank mates’ whistles even after being apart from them for more than 20 years.

The study, done by researchers at the University of Chicago, shows that dolphins have the longest social memory ever recorded for non-humans. According to the study, dolphins’ skills in recognizing the whistle sounds may be better than humans' facial recognition skills because human faces change over time.

“This shows us an animal operating cognitively at a level that’s very consistent with human social memory,” said Jason Bruck, a specialist in comparative human development, who conducted the study.

His study is published in the current issue of the Proceedings of the Royal Society of London B.

Bruck collected data from 53 bottlenose dolphins at six facilities that were part of a breeding consortium that kept decades of records on which dolphins had lived together.

Bruck compared the dolphins’ reactions to whistles of former tank mates with those of dolphins that were not familiar with each other. His initial studies showed that “dolphins get bored quickly listening to signature whistles from dolphins they don’t know.”

“When they hear a dolphin they know, they often quickly approach the speaker playing the recording,” Bruck said. “At times they will hover around, whistle at it, try to get it to whistle back.”

Bruck said dolphins even responded to calls they had not heard in decades.

In one notable example, Bruck played a recording of a female dolphin named Allie, who currently lives at the Brookfield Zoo, for Bailey, a female now in Bermuda.

The pair had last lived together at Dolphin Connection in the Florida Keys when Allie was two years old and Bailey was four. But 20 years and six months after their last contact, Bailey still recognized the recording of Allie’s signature whistle.

“Why do they need this kind of memory? I’m not sure they do,” Bruck said. “The cognitive abilities of dolphins are really well-developed, and sometimes things like this are carry-along traits. But to test whether this kind of social memory capacity is adaptive, we would need more demographic data from multiple populations in the wild to see if they experience 20-year separations.”

Here's a video about the experiment:


You May Like

Philippines, Muslim Rebels Try to Salvage Peace Pact

Peace process faces major setback after botched military operation to find terrorists results in bloody gunbattle between government forces, Moro Islamic Liberation Front fighters More

Republicans Expect Long, Expensive Presidential Battle

Political strategist says eventual winner will be one who can put together strongest coalition of various conservative groups that make up Republican Party More

Video New Wheelchair Is Easier to Use, Increases Mobility

Engineers have come up with a lever-operated design that makes use of easily accessible bicycle technology More

This forum has been closed.
Comment Sorting
Comments
     
by: Kitagawa Keikoh from: Nakameguro, TKO
August 10, 2013 9:34 AM
Dolphins need not meet so many mates in their life, so they are able to remember a few old mates for a long time.
Why does mass media like topics about dolphins, especially that dolphins may have some good abilities like human beings? Does they really think dolphins and human beings can communicate in the near future?

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Liberia's Almost Last Ebola Patient Grateful but Still Grievingi
X
Benno Muchler
March 26, 2015 3:41 PM
Beatrice Yardolo was to make history as Liberia’s last Ebola patient. Liberians recently started counting down 42 days, the period that has to go by without a single new infection until the World Health Organization can declare a country Ebola-free. That countdown stopped on March 20 when there was another new case of Ebola, making Yardolo’s story a reminder that Ebola is far from over. Benno Muchler reports from Monrovia.
Video

Video Liberia's Almost Last Ebola Patient Grateful but Still Grieving

Beatrice Yardolo was to make history as Liberia’s last Ebola patient. Liberians recently started counting down 42 days, the period that has to go by without a single new infection until the World Health Organization can declare a country Ebola-free. That countdown stopped on March 20 when there was another new case of Ebola, making Yardolo’s story a reminder that Ebola is far from over. Benno Muchler reports from Monrovia.
Video

Video Cambodian Land Grabs Threaten Traditional Communities

Indigenous communities in Cambodia's Ratanakiri province say the government’s economic land concession policy is taking away their land and traditional way of life, making many fear that their identity will soon be lost. Local authorities, though, have denied this is the case. VOA's Say Mony went to investigate and filed this report, narrated by Colin Lovett.
Video

Video US, South Korea Conduct Joint Military Exercises

The Eighth U.S. Army Division and the Eighth Republic of Korea Mechanized Infantry Division put on a well orchestrated show of force for the media this week during their joint military training exercises in South Korea. VOA’s Seoul correspondent Brian Padden was there and reports the soldiers were well disciplined both in conducting a complex live fire exercise and in staying on message with the press.
Video

Video Space Program Status Disappoints 'Last Man on the Moon'

One of the films that drew big crowds last week at the annual South by Southwest festival in Austin, Texas, tells the story of the last human being to stand on the moon, U.S. astronaut Eugene Cernan. It has been 42 years since Cernan returned from the moon and he laments that no one else has gone there since. VOA’s Greg Flakus reports.
Video

Video Young Filmmakers Shine Spotlight on Giving Back

A group of student filmmakers from across the United States joined President Barack Obama at the White House this month for the second annual White House Student Film Festival. Fifteen short films were officially selected from more than 1,500 entries by students aged 6 through 18. The filmmakers and their families then joined the president and a group of celebrities for a screening of their films. VOA’s Julie Taboh reports.
Video

Video VOA Exclusive: Interview with Afghan President Ashraf Ghani

Afghan President Ashraf Ghani, during his first visit as president to Washington, gave a one-on-one interview with VOA Afghan Service reporter Said Suleiman Ashna, about his request for a change in U.S. troop levels, the threat from the Islamic State, and repairing relations with the United States and Pakistan. The interview was held at Blair House, late Sunday, in Pashto.
Video

Video California Science Center Tells Story of Dead Sea Scrolls

The ancient manuscripts were uncovered in the mid-20th century, and they are still yielding clues about life and religious beliefs in ancient Israel. As VOA's Mike O'Sullivan reports, an exhibit in Los Angeles shows how modern science is bringing the history of these ancient documents to life.
Video

Video Angelina Jolie Takes Another Bold Step

Hollywood actress and filmmaker Angelina Jolie has revealed she had her ovaries and fallopian tubes removed to lower her odds of getting cancer. Doctors say the huge publicity over her decision will help raise awareness about the importance of cancer screening. VOA’s George Putic has more

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More