Sneaking a peek at my brother’s opened tabs for his environmental studies homework I find the following phrase: “…An accident of history we may be, but there is no question that Homo sapiens is the single most dominant species on Earth today.” Really? No question? This is a fairly common view, but I’ve always been a little confused by it. Exactly what criterion are we using for dominance? It can’t be numbers, because there are several species which are far more numerous than us. It can’t even be the extent of the globe we cover, since I think even plankton (ok, I know that’s not a single species or genus or anything, but I’m too lazy to do any detailed research on this) could lay claim to more of the earth than we do:
The dictionary definition of “dominance” is “exercising influence or control”, which says nothing about numbers or extent, so I suppose we can always call ourselves “dominant” by virtue of being able to exterminate other creatures more effectively than any other species. This is at least the focus of the page I quoted from, Chapter 13 of The Sixth Extinction by Richard Leakey and Roger Lewin. But while technically correct this seems to be a remarkably narrow view of dominance, because power exerted in this fashion holds almost as many risks for us as for the other creatures. Our actual power to change the earth in a controlled fashion is far more limited than most people seem to think. I guess we will find out soon enough, if the geo-engineering crowd gets its way.