"Greg Egan - Mitochondrial Eve" - читать интересную книгу автора (Egan Greg)

was also exactly the same as that of your siblings, your maternal first
cousins, second cousins, third cousins… until different mutations striking the
plasmid on its way down through something like 200 generations finally imposed
some variation. But with 16,000 DNA base pairs in the plasmid, even the 50 or
so point mutations since Eve herself didn’t amount to much.

The hologram dissolved from the micrograph into a multicoloured diagram of
branching lines, a giant family tree starting from a single apex labelled with
the ubiquitous image of Eve. Each fork in the tree marked a mutation,
splitting Eve’s inheritance into two slightly different versions. At the
bottom, the tips of the hundreds of branches showed a variety of faces, some
men, some women – individuals or composites, I couldn’t say, but each one
presumably represented a different group of (roughly) 200th maternal cousins,
all sharing a mitotype: their own modest variation on the common
200,000-year-old theme.

“And here you are,” said Cousin André. A stylised magnifying glass
materialised in the foreground of the hologram, enlarging one of the tiny
faces at the bottom of the tree. The uncanny resemblance to my own features
was almost certainly due to a snapshot taken by a hidden camera; mitochondrial
DNA had no effect whatsoever on appearance.

Lena reached into the hologram and began to trace my descent with one
fingertip. “You’re a Child of Eve, Paul. You know who you are, now. And
no-one can ever take that away from you.” I stared at the luminous tree, and
felt a chill at the base of my spine – though it had more to do with the
Children’s proprietary claim over the entire species than any kind of awe in
the presence of my ancestors.

Eve had been nothing special, no watershed in evolution; she was simply
defined as the most recent common ancestor, by an unbroken female line, of
every single living human. And no doubt she’d had thousands of female
contemporaries, but time and chance – the random death of daughterless women,
catastrophes of disease and climate – had eliminated every mitochondrial trace
of them. There was no need to assume that her mitotype had conferred any
special advantages (most variation was in junk DNA, anyway); statistical
fluctuations alone meant that one maternal lineage would replace all the
others, eventually.

Eve’s existence was a logical necessity: some human (or hominid) of one era or
another had to fit the bill. It was only the timing which was contentious.

The timing, and its implications.

A world globe some two metres wide appeared beside the Great Tree; it had a
distinctive Earth-from-space look, with heavy white cumulus swirling over the
oceans, but the sky above the continents was uniformly cloudless. The Tree
quivered and began to rearrange itself, converting its original rectilinear
form into something much more misshapen and organic – but flexing its geometry
without altering any of the relationships it embodied. Then it draped itself