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o 500 degrees centigrade and squeeze them to three hundred timesnormal pressures。 bacteria do it all the time without fuss； and thank goodness； for no larger organism could survive without the nitrogen they pass on。 above all； microbes continue toprovide us with the air we breathe and to keep the atmosphere stable。 microbes； including themodern versions of cyanobacteria； supply the greater part of the planet’s breathable oxygen。
algae and other tiny organisms bubbling away in the sea blow out about 150 billion kilos ofthe stuff every year。
and they are amazingly prolific。 the more frantic among them can yield a new generationin less than ten minutes； clostridium perfringens； the disagreeable little organism that causesgangrene； can reproduce in nine minutes。 at such a rate； a single bacterium could theoreticallyproduce more offspring in two days than there are protons in the universe。 “given an adequatesupply of nutrients； a single bacterial cell can generate 280；000 billion individuals in a singleday；” according to the belgian biochemist and nobel laureate christian de duve。 in the sameperiod； a human cell can just about manage a single division。
about once every million divisions； they produce a mutant。 usually this is bad luck for themutant—change is always risky for an organism—but just occasionally the new bacterium isendowed with some accidental advantage； such as the ability to elude or shrug off an attack ofantibiotics。 with this ability to evolve rapidly goes another； even scarier advantage。 bacteriashare information。 any bacterium can take pieces of genetic coding from any other。
essentially； as margulis and sagan put it； all bacteria swim in a single gene pool。 anyadaptive change that occurs in one area of the bacterial universe can spread to any other。 it’srather as if a human could go to an insect to get the necessary genetic coding to sprout wingsor walk on ceilings。 it means that from a genetic point of view bacteria have bee a singlesuperorganism—tiny； dispersed； but invincible。
they will live and thrive on almost anything you spill； dribble； or shake loose。 just givethem a little moisture—as when you run a damp cloth over a counter—and they will bloom asif created from nothing。 they will eat wood； the glue in wallpaper； the metals in hardenedpaint。 scientists in australia found microbes known as thiobacillus concretivorans that livedin—indeed； could not live without—concentrations of sulfuric acid strong enough to dissolvemetal。 a species called micrococcus radiophilus was found living happily in the waste tanksof nuclear reactors； gorging itself on plutonium and whatever else was there。 some bacteriabreak down chemical materials from which； as far as we can tell； they gain no benefit at all。
they have been found living in boiling mud pots and lakes of caustic soda； deep insiderocks； at the bottom of the sea； in hidden pools of icy water in the mcmurdo dry valleys ofantarctica； and seven miles down in the pacific ocean where pressures are more than athousand times greater than at the surface； or equivalent to being squashed beneath fiftyjumbo jets。 some of them seem to be practically indestructible。 deinococcus radiodurans is；according to theeconomist ； “almost immune to radioactivity。” blast its dna with radiation；and the pieces immediately reform “like the scuttling limbs of an undead creature from ahorror movie。”
perhaps the most extraordinary survival yet found was that of a streptococcus bacteriumthat was recovered from the sealed lens of a camera that had stood on the moon for two years。
in short； there are few environments in which bacteria aren’t prepared to live。 “they arefinding now that when they push probes into ocean vents so hot that the probes actually startto melt； there are bacteria even there；” victoria bennett told me。
in the 1920s two scientists at the university of chicago； edson bastin and frank greer；announced that they had isolated from oil wells strains of bacteria that had been living at depths of two thousand feet。 the notion was dismissed as fundamentally preposterous—therewas nothing to live on at two thousand feet—and for fifty years it was assumed that theirsamples had been contaminated with surface microbes。 we now know that there are a lot ofmicrobes living deep within the earth； many of which have nothing at all to do with theorganic world。 they eat rocks or； rather； the stuff that’s in rocks—iron； sulfur； manganese；and so on。 and they breathe odd things too—iron； chromium； cobalt； even uranium。 suchprocesses may be instrumental in concentrating gold； copper； and other precious metals； andpossibly deposits of oil and natural gas。 it has even been suggested that their tireless nibblingscreated the earth’s crust。
some scientists now think that there could be as much as 100 trillion tons of bacteria livingbeneath our feet in what are known as subsurface lithoautotrophic microbial ecosystems—slime for short。 thomas gold of cornell has estimated that if you took all the bacteria out ofthe earth’s interior and dumped it on the surface； it would cover the planet to a depth of fivefeet。 if the estimates are correct； there could be more life under the earth than on top of it。
at depth microbes shrink in size and bee extremely sluggish。 the liveliest of them maydivide no more than once a century； some no more than perhaps once in five hundred years。
as the economist has put it： “the key to long life； it seems； is not to do too much。” whenthings are really tough； bacteria are prepared to shut down all systems and wait for bettertimes。 in 1997 scientists successfully activated some anthrapores that had lain dormant foreighty years in a museum display in trondheim； norway。 other microorganisms have leaptback to life after being released from a 118…year…old can of meat and a 166…year…old bottle ofbeer。 in 1996； scientists at the russian academy of science claimed to have revived bacteriafrozen in siberian permafrost for three million years。 but the record claim for durability so faris one made by russell vreeland and colleagues at west chester university in pennsylvaniain 2000； when they announced that they had resuscitated 250…million…year…old bacteria calledbacillus permians that had been trapped in salt deposits two thousand feet underground incarlsbad； new mexico。 if so； this microbe is older than the continents。
the report met with some understandable dubiousness。 many biochemists maintained thatover such a span the microbe’s ponents would have bee uselessly degraded unless thebacterium roused itself from time to time。 however； if the bacterium did stir occasionallythere was no plausible internal source of energy that could have lasted so long。 the moredoubtful scientists suggested that the sample may have been contaminated； if not during itsretrieval then perhaps while still buried。 in 2001； a team from tel aviv university argued thatb。 permians were almost identical to a strain of modern bacteria； bacillus marismortui； foundin the dead sea。 only two of its genetic sequences differed； and then only slightly。
“are we to believe；” the israeli researchers wrote； “that in 250 million years b。 permianshas accumulated the