For years I have been seeing fluffy heads on germander speedwell plants and I just assumed they had gone to seed. Imagine my surprise when browsing through my new book about plant galls to come across a photograph like mine. This is not germander speedwell gone to seed, it is the work of a gall fly, Jaapiella veronicae. Apparently, the fly attacks the shoot tips and causes the topmost pair of leaves to cling together to form a hairy pouch that then contains numerous fly larvae.
This fly only attacks germander speedwell and germander speedwell is a pretty common flower but is there not a real risk here for the fly? It is totally dependent on germander speedwell surviving as a species. It almost certainly will but lets say it is discovered that human beings would be better off without germander speedwell for some reason and decided to eradicate it; we have eradicated species before, in fact we are doing it all the time. If germander speedwell went suddenly the gall fly would have no time to adapt and would go as well. What if there is something as dependent on the gall fly as the gall fly is on the speedwell? What if we humans are dependant on that mystery species?
An extreme example of course but that is surely why biodiversity is so vital and why we ignore it at our peril. Nature conservation is not just about conserving wildlife, it is not just about conserving pretty places to visit, it is about conserving all life on earth and that includes human beings.