Grey seals are able to form words and sing like humans, new research suggests.
A study, by University of St Andrews researchers, found three trained animals were able to copy speech, as well as notes from songs including Twinkle Twinkle Little Star and the Star Wars theme tune.
The findings suggest that grey seals have the skills to produce human language – although whether they would be able to understand meaning is a separate matter.
A seal called Hoover was documented copying human speech – including phrases like “how are you?” – at the New England aquarium in Boston, Massachusetts in the 1980s.
However, this does not necessarily mean that the mammals could learn to talk like humans.
Professor Vincent Janik, director of the Scottish Oceans Institute at the University of St Andrews, said: “While seals can copy such sentences, they would not know what they mean.
“We would have to investigate whether they are able to label objects vocally, which is a key requirement for actually talking about things.
“Our study suggests that they have the production skills to produce human language. Whether they can make sense of it would be the next question.”
The researchers worked with three grey seals from birth, training them to copy new sounds by changing their formants.
“Formants are emphasised frequency bands in our speech sounds,” Prof Janik said.
“They are parts of our speech sounds that we modify to encode information. For example, different vowels only differ in their formants.”
The seals were first trained to copy sequences of their own sounds, and then create melodies in their pitch.
Human vowel sounds were later presented to the animals, which they then copied.
“It takes hundreds of trials to teach the seal what we want it to do, but once they get the idea they can copy a new sound pretty well at the first attempt,” Prof Janik said.
Dr Amanda Stansbury, lead researcher, added: “I was amazed how well the seals copied the model sounds we played to them.
“Copies were not perfect but given that these are not typical seal sounds it is pretty impressive.
“Our study really demonstrates how flexible seal vocalisations are. Previous studies just provided anecdotal evidence for this.”
One seal, named Zola, was particularly good at copying melodies played to her, including up to 10 notes of Twinkle Twinkle Little Star.
As seals separate from their mothers when they are just two or three weeks old, the findings suggest they could be used to study speech disorders and test different methods for slower learners, the researchers said.
“Since seals use the same neural and anatomical structures as humans to produce these sounds, they provide a good model system in which to study how speech sounds are learned,” Prof Janik said.
“As they separate so early from their mothers, we can control what exactly they hear when, which makes such studies much easier than with humans who are exchanging sounds with parents for all of their development all the time.”
The research has been published in journal Current Biology.