|
Simon Davey studying lichens in Jersey |
Life on Earth is a near infinite mix of species with complex inter relationships. It is quite incredible how every group of animals and plants has evolved in a way that also gives the naturalist a perfect avenue of study and development of knowledge. Take birds, for instance. An embryo birder would have little difficulty in distinguishing a robin, a blue tit and a blackbird in the garden. As his experience develops, challenges such as leaf warblers and waders present themselves to give a puzzle equal to any Times crossword.
|
Lichenologists in a Dutch churchyard |
Personally, one of my greatest interests is in lichens. I suppose many would be put off lichens believing them to be far too complicated to get into. However, the ecological value of lichens makes them a challenge that is so worthwhile. Anyone with experience of suburban areas, and with even the slightest observation of the natural world, cannot fail to have noticed the scrambled egg like crusts growing on asbestos garage roofs, walls, or the enriched dog-pee zone at the base of trees in urban parks.
|
Xanthoria parietina |
This is the lichen
Xanthoria parietina. With something like 1800 species in Britain, lichens present a challenge that could keep any naturalist inspired and occupied for a lifetime. As with birds, some are easily identified, while the identification procedures to name others require a series of complex processes involving chemicals, high power microscopes and the accurate measurement of structures such as spores. Lichens are probably the fussiest group about the environment in which they can survive. The presence or absence of many allows an ecologist to make a rapid initial evaluation of the health and ecological importance of a site. It is well known that lichens cannot tolerate acid rain. It was probably lichens that caused environmentalists to take seriously the problems, to us all, of industrial air pollution more than anything else. A few groups of species, and especially lichens, beetles and hoverflies indicate by their presence or absence the ecological continuity and lack of negative disturbance in the places in which they live.