This also gives me the opportunity to pay tribute to my colleagues, whose dedication to bringing out their organs laughs in the face of a paucity of anything actually happening or indeed the regularity with which the same few things happen every year. So just cross off these headlines as they happen: 1) Queen's Xmas Message Of Hope 2) Di's Lonely Xmas 3) Xmas Cheer For Our Boys In Bosnia 4) Drunken Santa Who Headbutted Child Had "Emotional Problems", Court Told 5) Xmas Club Treasurer Goes Missing 6) And So Does The Chairman's Wife 7) Kiddies' Xmas Kitten Torn To Pieces In Boxing Day Hunt Horror (see picture) 8) Siberian Warbler Spotted In Suffolk (see picture) 9) Linda McCartney Caught With Goose 10) Another Quiet Xmas For John And Norma n Observer Shame. We seek cures for cancer and Aids and may indeed find a few but we simply don't know enough biology. The necessary knowledge will come from a broader vision: seeing the number of ways it is possible to be alive, therefore, is literally vital. Symbion is more than a quaint and tiny creature: it is a symbol of what is yet to be found out.The writer is a visiting research fellow at the centre for philosophy,London School of Economics..

JINGLE! And, today, the Captain's Christmas Service brings you an exclusive guide to some of the things you can look forward to reading in the newspapers over the festive season. But also for practical reasons - for the broad lesson to emerge is how naive we have been. This, we tell ourselves, is the age of biotechnology, when microbes will take over from industrial chemists. But what microbes? We hardly even begin to know what is out there.

But the people who are doing the work emphasise how little is known What we know now is just a glimpse of knowledge to come. Three domains sounds impressive - but there could be a dozen.Does it matter? For cultural reasons, certainly. It is a shame to partake of life and not know how wonderful it really is. In the 1970s, he found that the creatures known as "bacteria" represent two enormously different groups.

One group he called Eubacteria - now simply called "Bacteria"; the other he called Archaebacteria - now simply "Archaea". Each of these, he said, deserves to be called a "Domain": an even more embracing category than Linnaeus's Kingdoms. The animals, plants, fungi and the huge miscellany of "protists" then form a third domain, the Eukaryota.So this is life through modern eyes Since the 1950s, we have leapt a conceptual aeon We are at least two conceptual aeons ahead of Linnaeus. Indeed if plants, animals and fungi deserve to be called "kingdoms" then a dozen or so other distinct groups among the protists deserve kingdom status, too.

It seems that we human beings plus our cats and dogs and other familiar creatures are merely part of one division of one phylum among 35 in the kingdom of animals, which in turn is only one kingdom among 15 or so. In biology as in cosmology: eachdiscovery pushes us and our conceits further towards the periphery.Yet the greatest revelation of all is due to Carl Woese of the University of Illinois. The human gut parasite Giardia is distinct from all the rest; its ancestors might have been ploughing their own furrow for a couple of billion years. You might have supposed that we at least knew all the phyla - but Symbion has punctured any such complacency. It turned up, as great a novelty as animals can provide, right under our noses.Yet the animals as a whole represent only a sliver of life's variety.