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Chimpanzees bash out distinctive drum solos on the roots of trees as a form of 'signature' and to tell others in their group where they are.

Biologists studying the primates have found over the years that male chimps grip the buttresses of tree roots with their hands and beat them with their feet.

The noises produced - which is normally accompanied with loud hooting -  are known as pant calls, and can be heard more than half a mile (1km) away, even in the dense jungle.

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An example of a male chimpanzee  drumming a large tree root, which they use to tell others their location 

But now one group of scientists studying the animal in the Sonso Community in the Budongo Forest in Uganda, have found that this drumming contains distinctive rhythmic patterns that can be used to identify a specific individual.

Each male used a different number of beats and used a style of doublets and pauses that was distinct to them.

The researchers also discovered that the chimps tended to use drumming far more often when their group was travelling. They believe this may help keeps tabs on an individual's whereabouts.

Dr Katie Slocombe, a psychologist at the University of York who led the study, said she found she was able to identify individual chimps from their drumming style.

She believes her findings may also provide clues about how musical rhythm first began among humans.

She told Science: 'This shows that rhythmic abilities are not uniquely human.

'Coordinating movement over very long distances might have been why the earliest humans started to drum.'

Chimpanzees can roam over territories the size of Manhattan Island, which can make it difficult for the chimps to find each other.

They are known to use a series of hoots and bellows to communicate with each other, but some scientists have seen some males aggressively beat tree roots too.

It was thought that this might be a way of showing dominance by the male chimpanzees.

However, Dr Slocombe and her colleague's research, which a troop of chimpanzees for three years, suggests that this is not the case.

Their study, which is published in the American Journal of Physical Anthropology, analysed the social context of 293 hooting and drumming events by the troop's 13 males.

They found that while the older more experienced males did drum more than other troop members, their rank and whether other males or females were nearby played little role.

Instead, the decision to drum seemed to be more influenced by what the group were doing. 

Moment chimpanzee drums on a tree to identify itself

Male chimps like this one above tended to drum on trees more when they were on the move through the forest

If they were travelling, chimps drummed buttresses in 75 per cent of pant hoots but only 40 per cent of the time when resting and 10 per cent of the time when eating. 

Dr Slocombe found that travelling males tended to have their own distinctive flair. Recordings showed that the length of time each chimp spent drumming, their use for doublets and pauses and the number of beats varied by each animal.

Using computer software the researchers were able to identify the drummer 47 per cent of the time.

Dr Slocombe said: 'Drumming sequences produced with pant hoots may have contained information on individual identity and that qualitatively, there was individual variation in the complexity of the temporal patterns produced.

'We conclude that drumming patterns may act as individually distinctive long-distance signals that, together with pant hoot vocalizations, function to coordinate the movement and spacing of dispersed individuals within a community.'

She added that such behaviour could also be important in helping to allow rival chimpanzees keep their distance by knowing who is where.

The root drumming behaviour was only seen to be carried out by male chimps like the one above, but did not appear to be intended as a way of exerting dominance over others in their group in the area or to attract a mate