I realise that I meant to put up earlier my May column from Prospect. Almost time for the June column now, but here goes.
The notion that God has an inordinate fondness for beetles, credited to the biologist J. B. S. Haldane, retains a whiff of solipsism. For beetles are not so unlike us: multicellular, big enough to see, and legged. But God surely favours single-celled organisms far more. Beetles and humans occupy two nearby tips on the tree of life, while single-celled life forms have two of the three fundamental branches all to themselves: bacteria and archaea, so alike that it was only in the 1970s that the latter were awarded their own branch. Archaea have a different biochemistry to bacteria – their metabolism usually produces methane – and they are found everywhere, including the human gut.
Our place on the ‘tree of life’ now looks like it may be even more insignificant, for a team at the University of California, working with genomics pioneer Craig Venter, claims to have found hints of a fourth major branch in the tree, again populated only by single-celled organisms. These branches, called domains, are the most basic divisions in the Linnaean system of biological classification. We share our domain, the eukaryotes (distinguished by the way their cells are structured), with plants, fungi and yet more monocellular species.
Like most things Venter is involved in, the work is controversial. But perhaps not half so controversial as Venter’s belief, expressed in a panel debate titled ‘What is life?’ in Arizona in February, that all life on Earth might not even have a common origin. “I think the tree of life is an artefact of some early scientific studies, which are not really holding up”, he said, to the alarm of fellow panellist Richard Dawkins. His suggestion that there may be merely a “bush of life” only made matters worse.
Drop in the ocean
Despite the glee of creationists, there was nothing in Venter’s speculative remark that need undermine the case for Darwinian evolution. The claim of a fourth domain is backed by a little more evidence, but remains highly tentative. The data were gathered on a now famous round-the-world cruise that Venter undertook between 2003 and 2007 on his yacht to gather genomic information about the host of unknown microorganisms in the oceans. The rapid gene-analysing techniques that he helped to develop allow the genes of different organisms to be rapidly compared in order to identify evolutionary relationships between them. By looking at the same group of genes in two different organisms, one can deduce where in the tree of life they shared a common ancestor.
Using Venter’s data, Jonathan Eisen in California discovered that two families of genes in these marine microbes each seem to show a branch that doesn’t fit on the conventional tree of life. It’s possible that these genes might have been acquired from some unknown forms of virus (viruses are excluded from the tree altogether). The more exciting alternative is that they flag up a new domain. If so, its inhabitants would seem so far to be quite rare – a minor anomaly, like the Basque language, that has persisted quietly for billions of years. But since we are ignorant about perhaps 99 per cent of species on the planet, who knows?
The European Union is looking for big ideas. Really big ones. Its Flagship programme offers to fund two scientific projects to the tune of €1 bn over the next ten years. These must be “ambitious large-scale, science-driven, visionary research initiatives that aim to achieve a scientific breakthrough, provid[ing] a strong and broad basis for future technological innovation and economic exploitation in a variety of areas, as well as novel benefits for society.” In other words, they’ve got to achieve a heck of a lot, and will have truckloads of money to do so.
Six of the applications – all of them highly collaborative, international and interdisciplinary – have now been selected for a year of pilot funding, starting in May. They range from the highly technical to the borders of science fiction.
One promises to develop graphene, the carbon material that won last year’s physics Nobel prize, into a practical fabric for information technologies. Another proposes to truly figure out how the brain works; a third will integrate information technology with medicine to realise the much-advertised ‘personalized medicine’. But these things will all be pursued regardless of the Flagship scheme. More extraordinary, and therefore both more enticing and more risky, are two proposals to develop intelligent, sensitive artificial agents – characterized here as Guardian Angels or Robot Companions – that will help us individually throughout our lives. The sixth proposal (which received the highest rating) is to develop massive computer-simulation systems to model the entire ‘living Earth’, offering a ‘crisis observatory’ that will forecast global problems ranging from wars to economic meltdowns to natural disasters – the latter now all too vivid. The two initiatives to receive full funding will be selected in mid-2012 for launch in 2013.