The Mole: Going underground
Several species of shrew have taken to water in their search for prey items. In Europe, there are two near relatives called the desmans - one lives in Russia (Desmana moschata) and the other in the Pyrenees (Galemys pyrenaicus) which use long mobile noses as snorkels, turning them up so that they project above the water as their owners swim about busily searching for food. One insectivore group searched for its prey entirely underground, the mole. Judging from the structure of its paddle shaped forelegs and powerful shoulders, it is possible that the mole's ancestors were once water living shrews and the mole has simply adapted the same sort of actions for moving along its tunnels. Fur, underground, might be a mechanical handicap, but many moles live in temperate areas and they need fur for insulation. So it has become very short and without any particular grain so that it points in all directions and the animal can move forwards or backwards along its tight tunnels with ease. Eyes are of little use underground, would easily clog with mud, so they are much reduced in size. Moles locate their prey using their nose which is an organ of both smell and touch, since it is covered with many sensorybristles. At the rear, in has a short stumpy tail also covered with bristles which make it aware of what is happening behind it. The star nosed mole of America (Condylura cristata) has an additional device, an elegant rosette of fleshyfeelers around its nose which in can expand or retract. It may be simply a tactile organ or it may be a means of detecting changes in the chemical content of the air.