Soon we will be able to talk to the animals

From a talk by the curator of the wildlife section of the National Sound Archive, Richard Ranft, delivered at the British Library in London

At this time of the year in Britain, you only have to hear the dawn chorus of birdsong (which starts at about 4.30 in the morning) to appreciate the variety of sounds of nature. But creatures have been uttering sounds on earth for many millions of years, and there's a tremendous diversity of natural sounds.

At this time of the year in Britain, you only have to hear the dawn chorus of birdsong (which starts at about 4.30 in the morning) to appreciate the variety of sounds of nature. But creatures have been uttering sounds on earth for many millions of years, and there's a tremendous diversity of natural sounds.

Many animals make incidental sounds as a by-product of their movements - flying, running and swimming sounds - but other sounds are deliberately produced by animals for the purposes of communication.

Amphibians were perhaps the first vertebrates on land to be heard on earth when they evolved some 200 million years ago. There are today about 4,000 species of frogs and toads, each with its own distinctive voice. Reptiles such as snakes and geckos make communication sounds, but it is surprising to learn that many fish produce distinctive sounds underwater. The oceans are not "the silent world" that Jacques Cousteau once described them as. This next recording is of the mating call of the haddock.

Other creatures besides fish and walruses produce sounds underwater. Whales and dolphins have elaborate communication and sonar signals, and some crustaceans produce sounds. Just as in the tropics the air is filled with the sound of cicadas and other insects, the tropical oceans reverberate with the noisy crackling made by the snapping shrimp.

The most vocal animals are the birds. Some, such as the puffin, use their voice only occasionally, but in many species the voice is used frequently. Some birds have a vocabulary of around 20 calls, some of them with precise meanings. For example, a chaffinch has one alarm call to warn of the presence of a bird of prey, and a different one for a terrestrial predator such as a cat.

Many birds have evolved very complex songs, which are primarily used to attract mates and defend breeding territories. The capercaillie, a bird of the Scottish Highlands, has a peculiar song which has been likened to the sound of wine being emptied out of a bottle.

In true songbirds, sound production is highly developed and quite musical to human ears. Some birds are able to mimic other birds and animals, and even man-made sounds, as we heard from the bowerbird. There is a recording, for example, of a blackbird, recorded recently outside offices in London, apparently mimicking the sound of a computer modem. No animal has evolved the sophistication of human speech. However, many mammals have sounds that are outside the range of human hearing. A recent discovery is that elephants can produce infrasound. Low-frequency sounds travel further than high frequency ones, and the elephants use these sounds to maintain contact over large distances in the African bush.

From the largest land animals to some of the very smallest, the insects. Everyone is familiar with the stridulations of grasshoppers and crickets in late summer, but there are other, smaller insect musicians that escape most people's attention. Planthoppers are tiny sap-sucking insects, a couple of millimetres in length. In their miniature world, grass stems are the size of tree trunks, yet these tiny bugs tap out complex drumming patterns on to the plants on which they sit. These sounds cannot be heard more than a few millimetres away and have to be recorded with special sensors in direct contact with the plant. Each bug has its own distinct beat.

New species are often discovered by their voices. Recently it was discovered that the common pipistrelle bat in Britain is in fact two similar species. One has a higher-pitched voice and is now called the soprano pipistrelle. Studies of animal sounds are also yielding clues to the origins of human language.

Charles Darwin in 1872 advanced the scientific discussion on the origins of animal sounds and their meaning, but he doubted whether anyone would ever explain them fully. He could not have foreseen the technical developments that have allowed us to understand so much more. New techniques are being developed that allow interactive dialogues via a computer that will soon enable us to really "talk to the animals".