Go Back   Palimpsest > Reviews > Book Reviews

Thread Tools Display Modes
Prev Previous Post   Next Post Next
Old 7th Jun 2005, 15:33   #1
John Self
suffers from smallness of vision
John Self's Avatar
Join Date: 27 Jun 2003
Location: Belfast
Posts: 15,939
Default Armand Marie Leroi: Mutants

I know how conjoined twins come to be formed; this morning I did not. I can hardly pay greater tribute to the explicatory gifts of Armand Marie Leroi than to say that. And yet there is much more to say about his book Mutants: On the Form, Varieties and Errors of the Human Body, even though I am only on page 67. The big thing, which I want to share now, is this: Leroi's truthful, beautiful account of how humans can develop with deformities and errors - and, more importantly, how so many do not - is written with an elegance and brilliance that even the most artful fiction rarely matches. The man is not only a scientist, but a poet. Here he is, explaining that because of inherited defects we obtain from our parents, and our parents' parents, and our parents' parents' parents:

the average newly conceived human bears three hundred mutations that impair its health in some fashion. No one completely escapes this mutational storm. But - and this is necessarily true - we are not all equally subject to its force. Some of us, by chance, are born with an unusually large number of mildly deleterious mutations, while others are born with rather few. And some of us, by chance, are born with just one mutation of devastating effect where most of us are not. Who, then, are the mutants? There can be only one answer, and it is one that is consistent with our everyday experience of the normal and the pathological. We are all mutants. But some of us are more mutant than others.
Although the book contains many illustrations and photographs and case histories of human mutations, it is not a freak show, and is mostly interested in what goes wrong as a way of discovering how, otherwise, it so often goes right. Here is an extraordinary description of the early life of an embryo:

Eighteen days after conception an embryo is just a white, oval disc about a millimetre long. It has no organs, just three tissue layers and a geometry. ... Within the next ten days all this will have changed. The embryo will be recognisably an incipient human - or at least some sort of vertebrate, a dog, a chicken or perhaps a newt. It will have a head, a neck, a spinal column, a gut; it will have a heart.

The first sign of all this future complexity comes on day 19 when a sheet of tissue, somewhat resembling the elongate leaf of a tulip, forms down the middle of the embryo. The leaf isn't entirely flat: its edges show a tendency to furl to the middle, so that if you were to make a transverse section through the embryo you would see that it forms a shallow U. By the next day the U has become acute. Two more days and its vertices have met and touched in the middle of the embryo, rather as a moth folds its wings. And then the whole thing zips up, so that by day 23 the embryo has a hollow tube that runs most of its length, the nature of which is now clear: it is the beginning of the mighty tract of nerves that we know as the spinal column. At one end, you can even see the rudiments of a brain.

Even as the nerve-cord is forming, the foundations of other organs are being laid. Two hitherto inconspicuous tubes, one on either side, then unite to make a single larger tube running the length of the embryo's future abdomen, an abdominal tube that echoes the neural tube on its back. Within a few days this abdominal tube will begin to twist and then twist again to become a small machine of exquisite design. Though it still looks nothing like what it will become it already shows the qualities that led William Harvey to call it 'the Foundation of Life, the Prince of All, the Sun of the Microcosm, on which all vegetation doth depend, from whence all Vigor and Stength doth flow.' On day 21 it begins to beat.
When was science ever this much fun - or this beautifully described? I am going to enjoy the rest of this book. Further bulletins as events warrant.
Reading Vasily Grossman, Life and Fate | Asylum | Book List
John Self is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT +1. The time now is 11:46.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.