And this one’s no exception: "Darwin was wrong" on the cover of New Scientist, no less. (& in smaller type: cutting down the tree of life.)
This leads to a story about the significance of horizontal gene transfer to our understanding of evolutionary relationships. But why the headline (which will probably be grist to the anti-evolutionary mill…)? The idea of HGT is neither new, nor particularly controversial. Scientists have known for at least a decade that prokaryotes are quite promiscuous about passing around bits of DNA. And we know, too, that it can happen in eukaryotes: transfer of DNA between chloroplasts (& mitochondria) & their host cells’ nuclei has been well documented. (And this can sometimes make it difficult to work out prokaryote phylogenies.) So we can infer that HGT was just as rife among the prokaryote inhabitants of the early Earth – and hence, at that stage you couldn’t really describe what was going on as being represented by a ‘tree of life’.
We owe the metaphor of the ‘tree of life’ to Charles Darwin, who used it as a way of representing the concept of descent with modification. So, does the prevalence of HGT among prokaryotes, especially back on that early Earth, mean that Darwin was wrong?
Well – like all scientists – he was wrong about quite a lot. He was spectacularly wrong about how inheritance worked, for example. But Darwin developed the tree metaphor to represent the interrelatedness, & shared ancestry, of the organisms with which he was most familiar: animals & plants. It was a powerful metaphor then, & remains so today. And the recognition that, at the prokaryote level, a better metaphor might be of a web does nothing to topple the theory of evolution as the best explanation we have for how the wonderful diversity of life has developed.
Unfortunately, that’s how that cover headline could, & probably will, be interpreted. And both headline & article have been dissected already, here for example. But it does lead to the question: just what is the responsibility of the media to report accurately on what’s going on in science? Jason Rosenberg asked this question, over on Evolutionblog. Among others, it drew a response from the editor of New Scientist:. Making the point that there is an awful lot of competition for readership, he says:
To get noticed, you have to play the game to some extent. You have to find exciting new stories and sell them in exciting, sexy (and sometimes controversial) ways. That doesn’t go down well with the purists, but I’d always argue that it’s better to have a million people reading a "dumbed down science rag" than a few hundred people reading real science and everybody else doing something else.
But you can "dumb down" (a dreadful phrase!) without sacrificing accuracy – Carl ZImmer’s blogposts & books are an excellent example of how to communicate about science in a wonderfully engaging way that is also an accurate representation of the current state of play. So why is it so often deemed necessary to go for what could be described as a tabloid approach? As another commentator on Jason’s blog says:
Being a good writer and being exciting are components of science journalism.
But don’t forget that the top three criteria are:
1. scientific accuracy
2. scientific accuracy
3. scientific accuracy
Everything else is window dressing.
And in terms of conveying what science is about, that window dressing often does everyone a disservice.