The tour may have taken in five countries and culminated in a banquet with the Queen, but the centrepiece event took place not at Buckingham Palace, but in a small room in Burlington House in Piccadilly, Central London, where he had been invited to address the Linnean Society of London.

Emperor Akihito specialises in taxonomy (the classification of species) and Carl Linnaeus is one of his intellectual heroes.

He delivered the tercentenery address yesterday – Linnaeus was born 300 years ago this month – in front of portraits of Charles Darwin and Alfred Russel Wallace, pioneers of evolutionary theory who drew on Linnaeus’s work. The Emperor described the history of binomial classification and its introduction to Japan, and discussed his own research into goby fish.

The Emperor also told an audience of about 100 scientists, including Sir David Attenbor-ough and Richard Fortey, a palaeontologist at the Natural History Museum, that taxonomy was undergoing a profound change.

“I think that the analysis of mitochondrial DNAs will open up great possibilities of discovering new species which cannot be distinguished morphologically, but which can be clearly distinguished at a molecular biological level,” he said.

Sir David said that the Emperor’s interest in the subject highlighted the importance of taxonomy, an unfashionable discipline that is fundamental to biology and conservation.

“Linnean classification is the foundation stone of modern taxonomy, and zoology would not exist without taxonomy,” he said. “It is vitally important to conservation. You can’t know what is flourishing and disappearing unless you can recognise it first. It has to be classified and named.”

Dr Fortey, responding on behalf of the Linnean Society, said that the work of taxonomists would be critical to preserving biodiversity against threats such as the rising human population and global warming.

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