Study shows teeth are testament to diet
Are we really 'what we eat' as the common platitude says? Apparently so, according to a team of scientists from the Netherlands, Switzerland and the United Kingdom: they have shown that our teeth are literally shaped by what food we choose to put in our mouths. Research from the team shows that evidence from teeth can be used to determine what has been eaten by a particular animal. This means scientists can now find out about wild animals' diets without having to look at the contents of their stomachs. The team also claim their method could be use to investigate diets of extinct animals such as giant marine reptiles and dinosaurs. Writing in the Journal of the Royal Society Interface, the team explain that the roughness of tooth surfaces can reveal what an animal has been eating. This shows there is a close link between roughness of teeth and diet, with teeth from animals that eat hard foods having rougher surfaces than those from animals that eat soft foods. Professor Mark Purnell from the University of Leicester, comments: 'Run your tongue over your teeth. Some may feel rougher than others. The question we are trying to answer is can the roughness of the tips of teeth, worn by contact with food, be used to work out what an animal has been eating? But before we can start to answer that question, we need to ask, what is roughness? This is tricky to measure. Smooth and rough surfaces are intuitively easy to distinguish, but is tree bark rougher than a road surface? Is the microscopic surface of chalk rougher than cheese? It's hard to make the comparison. 'But the question does matter. For example, as hip replacements wear, do they get rougher or smoother? If an engine cylinder is too smooth it won't retain enough oil on its surface, leading to friction and seizing, but how smooth is too smooth? In order to answer questions like this, engineers have been working on ways to measure roughness for decades. International standards are now being developed, based on new ways of measuring surfaces very precisely using special 3-D microscopes, and it is this approach that has been applied to the teeth in this study.' These new methods will provide a useful new way of investigating fish diets. This means researchers will be able to see how changes in diet can control the disappearance of a species, or the evolution of new ones - and will be especially useful for analysing fossils of animals whose diets are hard to determine. Ole Seehausen was the team member responsible for identifying stomach contents. He adds: 'To our surprise, we found that in some cases tooth roughness is a more reliable guide to diet than looking in a fish's stomach, because stomach contents tell you only what an animal was eating in the few hours before it was caught, not what it usually eats.'For more information, please visit:University of Leicester:http://www2.le.ac.uk/
Countries
Switzerland, Netherlands, United Kingdom