British scientists have taught a group of seals how to copy human sounds and one of them how to sing the popular lullaby Twinkle, Twinkle Little Star.
Researchers from the University of St Andrews worked with three young grey seals from birth to determine their natural repertoire and say the research could help others study speech disorders.
The seals were then trained to copy new sounds, such as vowels and melodies, by changing their formants, the parts of human speech sounds that encode most of the information that we convey to each other.
One seal, named Zola, was ‘particularly good’ at the musical side of things – correctly copying up to 10 notes of songs, including the classic jingle of ‘Twinkle, Twinkle’.
British scientists have taught a group of seals how to copy human sounds and sing tunes including Twinkle, Twinkle Little Star – and now the research could help others study speech disorders
The study, published in the journal Current Biology, found that the seals used their vocal tract in the same way as us – unlike our closest relatives in the animal world, monkeys and apes.
Now scientists working on disorders can use seals as a new model system to study the ‘nature vs. nurture’ element of our speech development.
Researchers Dr Amanda Stansbury and Professor Vincent Janik, of the Scottish Oceans Institute (SOI) at St Andrews worked together on the project.
They taught the seals to sing by playing sounds close to their natural vocal range, before rewarding them with treats when they successfully copied them.
Dr Stansbury, who now works at El Paso Zoo in Texas, said: ‘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.’
Professor Janik, Director of the SOI, said: ‘This study gives us a better understanding of the evolution of vocal learning, a skill that is crucial for human language development.’
He added: ‘Surprisingly, non-human primates have very limited abilities in this domain.
‘Finding other mammals that use their vocal tract in the same way as us to modify sounds informs us on how vocal skills are influenced by genetics and learning and can ultimately help to develop new methods to study speech disorders.’
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.
The study, published in the journal Current Biology , found that the seals used their vocal tract in the same way as us – unlike our closest relatives in the animal world, monkeys and apes
‘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,’ Professor 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.’
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 Janik added: ‘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.’
