
Scientists pull living microbes, possibly 100M years old, from beneath the sea - walterbell
https://www.sciencemag.org/news/2020/07/scientists-pull-living-microbes-100-million-years-beneath-sea
======
sradman
The paper _Aerobic microbial life persists in oxic marine sediment as old as
101.5 million years_ [1]:

> Our results suggest that microbial communities widely distributed in
> organic-poor abyssal sediment consist mainly of aerobes that retain their
> metabolic potential under extremely low-energy conditions for up to 101.5
> Ma.

> Dominant bacterial groups included Actinobacteria, Bacteroidetes,
> Firmicutes, Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria,
> and Deltaproteobacteria (Fig. 3b, c) with a minor fraction of Chloroflexi
> (0– 2.6%).

It seems that it is the conditions that extends life since such a diverse
community of aerobes was "reanimated".

[1]
[https://www.nature.com/articles/s41467-020-17330-1](https://www.nature.com/articles/s41467-020-17330-1)

------
est31
I've heard that there is a hard limit of about 1 million years to recover
ancient DNA because of deterioration processes [1]. Wouldn't their DNA have
deteriorated by now? Or is it being constantly repaired?

[1]:
[https://en.wikipedia.org/wiki/Ancient_DNA](https://en.wikipedia.org/wiki/Ancient_DNA)

~~~
Knufen
You can 'reverse engineer' DNA. Though the DNA strand itself deteriorates
rather quickly given the time scales. The peptide bond are extremely robust
and can be used to recreate the original DNA string or at least some semblance
of it.

~~~
gus_massa
Some parts of the DNA are not transcribed, for example the "Promoters"
[https://en.wikipedia.org/wiki/Promoter_(genetics)](https://en.wikipedia.org/wiki/Promoter_\(genetics\))
They are important so some proteins are build only when the they are needed.
For a more concrete example, see
[https://en.wikipedia.org/wiki/Lac_operon](https://en.wikipedia.org/wiki/Lac_operon)

------
rajekas
Makes me think that panspermia isn't so outlandish. 100 million years will get
you from star system to star system with plenty of time to spare.

~~~
waheoo
Has work been done on figuring out how long it would take to develop
DNA/RNAthrough evolution?

I.e. has the earth been around long enough?

~~~
ericbarrett
The fossil record indicates life on Earth appeared no later than about
800,000,000 years after it first formed, and possibly much sooner.

While there’s no real evidence for panspermia, it is a fun topic to read
about. I recall one hypothesis is that DNA (or RNA) based life evolved shortly
after the Big Bang (500,000 years?) when the universe was a balmy lumpy-gas
bath of 0-100C. If this were true, it would follow that life is as pervasive
as the cosmic background radiation and we should expect to find it in every
crevice. Mind-bending.

~~~
ardy42
> I recall one hypothesis is that DNA (or RNA) based life evolved shortly
> after the Big Bang (500,000 years?) when the universe was a balmy lumpy-gas
> bath of 0-100C. If this were true, it would follow that life is as pervasive
> as the cosmic background radiation and we should expect to find it in every
> crevice. Mind-bending.

That's pretty unbelievable, since at that time stars hadn't formed to create
heavier elements, so the elements available were hydrogen, helium, and a
little bit of lithium. DNA is mostly carbon and nitrogen.

------
cerealbad
Anyone with a passing interest in this or adjacent fields should check out the
Deep Carbon Observatory website.

[https://deepcarbon.net/worlds-oldest-groundwater-supports-
li...](https://deepcarbon.net/worlds-oldest-groundwater-supports-life-through-
water-rock-chemistry)

[https://en.wikipedia.org/wiki/Sulfate-
reducing_microorganism...](https://en.wikipedia.org/wiki/Sulfate-
reducing_microorganisms)

------
rbartelme
It's a big logical leap to the conclusion that this will "doom us all". It's
even sillier to be afraid of sediment core incubation experiments with
destructive sampling techniques. Don't you think?

~~~
zipwitch
SF author and marine biologist Peter Watts has a trilogy on a very similar
premise, where an early "fork" of life (that is actually _more_ efficient than
our entire tree of life) got stuck down in the ocean depths at the dawn of
time, until we accidentally bring it up.

[https://rifters.com/real/shorts.htm](https://rifters.com/real/shorts.htm)

------
freedomben
Related: I recently read "The Story of Earth" by Robert Hazen and it's a
fascinating read. Highly recommend. The author also has a few Great Courses
courses. "The Origin and Evolution of Earth" is a companion to the book (it
covers much of the same material) but the two together left me with
significant retention of the material. It's fascinating to go out hiking now
with my kids and be able to entertain and educate them with facts about the
rocks and formations we are hiking on :-)

------
dumbfoundded
I wonder if there's any depth we've searched where we haven't found life. It
looks like life is everywhere we look. Is there anywhere on Earth there isn't
some microbe living?

~~~
Someone
Reading [https://www.nationalgeographic.com/news/2017/04/deepest-
life...](https://www.nationalgeographic.com/news/2017/04/deepest-life-earth-
mariana-trench-astrobiology-science/), scientists think temperatures above
250F (120 °C) aren’t compatible with life as we know it (carbon-based, using
water), and, because of that, there isn’t life below 6 miles down.

Reading
[https://en.wikipedia.org/wiki/Methanopyrus](https://en.wikipedia.org/wiki/Methanopyrus),
about a microbe that “can survive and reproduce at 122 °C”, that limit may be
based on observation, rather than first principles. Regardless, I would take
it with a grain of salt.

~~~
close04
Some archaea species like Geogemma barosii [0] can survive and reproduce at
temperatures above 121 °C (the temperature used in many autoclaves for
example).

[0]
[https://en.wikipedia.org/wiki/Strain_121](https://en.wikipedia.org/wiki/Strain_121)

~~~
dumbfoundded
That's pretty awesome that the only limitations of life on Earth appear to be
pressure and temperature.

------
ncmncm
Maybe now the bacteria revived from 40Mya amber are believable.

------
imvetri
Isn't this a repost ? I remember reading similar article last year

------
42droids
It’s 2020. What can go wrong?

~~~
vz8
Remember the Mayan calendar brouhaha over 2012? They just forgot to carry the
1.

And here we are.

~~~
felipemnoa
Would have made a great movie. "The Mayans were off by 8 years"

~~~
nkrisc
I'm sure the Mayan's original paper they submitted for peer review had the
appropriate margins or error detailed, it was just lost once the newspapers
picked it up.

~~~
felipemnoa
Great point!

------
tomcam
They don’t look a day over 61 million

~~~
Igelau
Does my pseudopod look fat to you? How about now?

~~~
tomcam
Dear, you always look wonderful to me.

------
benmcnelly
Do you want zombies, this is how you get zombies... /kidding of
course(mostly)!

~~~
walterbell
But, but .. we did that in 1997-2005 for Spanish flu and nothing (?) happened.

[https://www.nature.com/articles/437794a](https://www.nature.com/articles/437794a)

 _> It is thought to have killed 50 million people, and yet scientists have
brought it back to life … Working out how it arose and why it was so deadly
could help experts to spot the next pandemic strain and to design appropriate
drugs and vaccines in time, they say. But others have raised concerns that the
dangers of resurrecting the virus are just too great. One biosecurity expert
told Nature that the risk that the recreated strain might escape is so high,
it is almost a certainty._

Grave digging: [https://www.cdc.gov/flu/pandemic-
resources/reconstruction-19...](https://www.cdc.gov/flu/pandemic-
resources/reconstruction-1918-virus.html)

