Inam Ansari
Washington: The European mole can burrow through the soil with ease with its powerful digging shovels and the same applies to the Australian marsupial mole. Even though the two animal species live far apart, they have developed similar organs in the course of evolution. Science speaks of "convergent evolution" in such cases, when animal, but also plant species independently develop features that have the same shape and function. There are many examples of this: Fish, for example, have fins, as do whales, although they are mammals. Birds and bats have wings, and when it comes to using poisonous substances to defend themselves against attackers, many creatures, from jellyfish to scorpions to insects, have all evolved the same instrument: the venomous sting. Identical characteristics despite lack of relationship It is clear that scientists around the world are interested in finding out which changes in the genetic material of the respective species are responsible for the fact that identical characteristics have evolved in them, even though there is no relationship between them. The search for this is proving difficult: "Such traits - we speak of phenotypes - are of course always encoded in genome sequences," says plant physiologist Dr. Kenji Fukushima of the Julius-Maximilians-Universitat (JMU) Wurzburg. Mutations - changes in the genetic material - can be the triggers for the development of new traits. However, genetic changes rarely lead to phenotypic evolution because the underlying mutations are largely random and neutral. Thus, a tremendous amount of mutations accumulate over the extreme time scale at which evolutionary processes occur, making the detection of phenotypically important changes extremely difficult. Novel metric ...
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