Given my past involvement with Greenpeace, the fact that I have changed my mind about genetically engineered crops (GMOs) makes me an apostate. Continuing my heretic writings, I will try to show today that biotechnology, specifically genetic engineering, can be good for biodiversity, specifically genetic diversity.
In environmentalist discussions it is often presupposed, without much felt need of further justification, that genetically engineered crops are bad for biodiversity. Why this is so? There is a number of reasons standing behind this conviction. Most of all, biodiversity is often identified with intensive agriculture, which itself is identified with biodiversity loss. The latter link is indeed comprehensible: monocultures, aggressive use of pesticides and herbicides, nitrogen run-off are typical characteristics of industrial agriculture. And they have rather unambiguously negative effects on biodiversity (see, e.g., here and here). However, even though the two commercially dominant types of genetically engineered crops (various variants of Roundup Ready and bt crops) are mostly used in industrial agriculture settings, there is no logical link between GMOs and this type of agriculture. This is a clear non sequitur when one criticises genetic engineering because of her opposition to industrial agriculture.
Another reason for considering GMOs to be bad for biodiversity is that biodiversity is sometimes divided in “good diversity” and “bad diversity”. The former is then restricted to species that are considered “native”, while the latter includes not-so-good “exotics” or “(invasive) alien species”. From this perspective, GMOs are even worse–they are not just “alien”, they are “artificial”! Here, again, I believe that there is a misconception. First of all: what constitutes a native species? Species “migrate”, sometimes with, sometimes without human help. There are hardly any “untouched” ecosystems left on Earth, most of them having been modified or influenced by human activity in one way or another–including changes in species composition. Thus, restricting “good” biodiversity to the diversity of native organisms is simply naive. Second, there is no logical reason for constraining biodiversity to some arbitrarily defined domain. The term itself suggests that what it “pays attention” to is diversity of biotic things. It does not matter where they come from.
The fact is, however, that genetically engineered crops are not “worse” in any objective respect than are any other crops. They are not bad for biodiversity. But they may be good for it. There are two reasons for that. First, rather trivially, if we refuse the idea that “artificial species” do not contribute to “good” biodiversity, then the fact that genetically engineered crops can be considered new species or at least new varieties makes biodiversity increase when they are introduced (at least on a large scale and provided that they are not cultivated in monocultures–see above).
The second positive contribution of genetic engineering to biodiversity is the main point of my post. Biodiversity, specifically genetic diversity, is often considered a carrier of options. This means that the gene sequences of natural plants and animals can be useful for us in the future, e.g., if they code for the synthesis of certain bioactive compounds or if they are responsible for certain useful traits such as drought resistance. However, before the advent of biotechnology, only those traits were important which could be found in species that are closely related to our agriculturally important crops and livestock, so that these traits could possibly be bred into them by means of conventional breeding methods. With biotechnology, this restriction does not hold any more: genes from any living thing can potentially be inserted into any crop/livestock DNA. This means that the value of genetic diversity to agriculture increases vastly. If we use this argument in debates about the protection of ecosystems, we might be able to convince more political and societal actors that it is a sensible thing to do. Appealing to nature’s beauty and intrinsic value has not proven very helpful to date. Thus, in an indirect way, genetic engineering can be beneficial for biodiversity, contrary to what most environmentalists believe.
The Sceptical Economist 
Well, I could have seen it coming when I began reading the article: of course, by just making it a numbers’ game, the introduction of new genes or genes from another species into a second’s gene pool, biodiversity is increased. that is, if biodiversity is strictly defined by counting the various gene variants and their carriers that “roam the Earth”. However, the threat (if there is any) to biodiversity could come from another angle, and people a little more sophisticated than the critics that you paint (maybe they are that dull at Greenpeace, I don’t know), people thinking more deeply about the issue have another argument: if you cultivate organisms that get “ahead of evolution” by recombining genes or introducing totally artificial genes (certainly not far off and already on the agenda), then you might (might!) one day create an organisms that is so far advanced over its peers and other co-habitants that it finally eradicates therm via the “survival of the fittest”. Like when humans came to certain islands, then certain animals (the emu, turtles etc.) just vanished. And these eradications can be so profound that these organisms will not survive anywhere. I know all this is theory, but not less than your idea of “enriching” biodiversity by playing dice with gene recombination.
I do not see why this “danger” is supposed to be specific to genetically engineered organisms. Especially as genetic engineering is relatively precise. Such “super-organisms” you invoke here might just as well arise naturally. And “ahead of evolution” is a very seldom term. In fact, what we do while engineering new organisms is the same which occurs naturally through mutations. Evolution is just the set of “mechanisms” that makes some of thus developed organisms survive. So, as I understand it, there is no such thing as “ahead of evolution”.