Dear colleagues,

Thanks to Ferdinando for yet another very stimulating contribution. If we look at biodiversity change in the marine realm, by far the largest living space on earth, it is certainly good to take both the unknown and known into consideration.

Are threatening factors not becoming more and more evident through ongoing exploration and research? What about fisheries and pollution, including waste dumping? Certainly we do not fully understand all interrelationships (we don't even know all the species!), but aren't there indications that, for example, some fish species might be threatened at least locally by over fishing and that marine food webs (including human consumption) can be affected by pollution? Globally there may be no sign of biodiversity decrease so far, but locally I think there are potential threats that - admittedly - need to be studied in more detail. But as a first step, public awareness has to be raised in order to highlight why such studies are highly important. Who apart from scientists (including taxonomists) should do that?

I agree that the habitat level is important, but then immediately the question of scale arises as habitat is an operant definition with respect to the organisms that are unknown, studied, monitored, potentially threatened, locally extinct, etc.

Franz Uiblein
Fish taxonomist and ecologist
Institute of Marine Research, Bergen, Norway