A once indigestible problem

UK researchers reveal that the ability to digest cellulose, the most common organic material produced by life, is not such a rare talent in the animal kingdom as scientists previously thought. Angus Davison of the University of Nottingham and Mark Blaxter of the University of Edinburgh were aware that a few animals possess cellulase enzymes, which is capable of breaking down the tough sugar-based polymers produced by plants. However, scientists were puzzled as to why an enzyme hundreds of millions of years old should not be more widespread in the animal kingdom. After all, cellulose would make a ready fuel source for any organism if it could be broken down. Now, the researchers have discovered that cellulases are not so rare after all, turning up in earthworms, sea urchins, lobsters, and bees. The researchers suggest that our ancient evolutionary ancestors may also have had cellulase enzymes, although why we lost them remains a mystery.