68 Scientific American, April 2020 Illustration by Matt Collins
ANTI GRAVITY
THE ONGOING SEARCH FOR
FUNDAMENTAL FARCES
Steve Mirsky has been writing the Anti Gravity column since
a typical tectonic plate was about 36 inches from its current location.
He also hosts the Scientific American podcast Science Talk.In June 2018 the journal Science published research showing
that chlorophyll-containing blue-green algae, also known as cya-
nobacteria, that were grown in extremely red light could carry
on some photosynthesis despite the light’s low energy.
Soon after, the magazine Cosmos ran with that finding to pro-
duce a nice article entitled “Pushing the Limit: Could Cyanobac-
teria Terraform Mars?” The subhead read: “The discovery that
blue-green algae can photosynthesize in extremely low light has
implications for astrobiology.”
Then, on January 19, 2020, Senator Rand Paul of Kentucky cit-
ed the article in a tweet that also said, “Despite climate alarmist
predictions, humans will likely survive for hundreds of millions
of years into the future. In the meantime, we should begin cre-
ating atmospheres on suitable moons or planets.” He then tweet-
ed, “With so many billionaires about, why not a private prize of
$10 million for the scientist who genetically creates an O 2 produc-
ing organism that will thrive in the frigid, methane lakes of Titan?”
These notions struck me as, well, wacky. I knew that species
don’t last for hundreds of millions of years. And making an organ-
ism to terraform Saturn’s moon Titan, if even possible, would
undoubtedly cost more than some billionaire’s chump change.
So I contacted Emory University paleontologist and geologist
Anthony J. Martin. He noted that another species of hu mans, Homo
ne and er thal en sis, “only lasted [approximately] 350,000 years
before going extinct.” Our species, Homo sapiens, has tens of
thousands of years to go be fore we even catch up to the Neandertals.
I then wrote to University of Edinburgh evolutionary biolo-
gist Steve Brusatte. “If we make it another 10 million years, we’ll
be a record setter,” Brusatte wrote back. “I can’t think of any spe-
cies that has approached that type of longevity. Ten million years
ago there wasn’t even a human lineage—it would still be anoth-
er few million years before our ancestors split from the chimps.”
(Podcasts with Martin and Brusatte about books they’ve written
are at ScientificAmerican.com.)
On to tweet two. A guest blog on our Web site in 2016 did in
fact claim that Titan might be the second-best place in the solar
system (in some ways better than the moon or Mars) for humans
to live—a loooooog time from now.
Curious about the idea of oxygenating Titan with an engi-
neered microorganism to be created on the cheap, I wrote to a
planetary scientist. That person, who requested anonymity, re-
plied, “I ap preciate that Senator Paul is not a planetary scientist
nor—apparently—an economist,
but it’s clear he could thrive as a
humorist. I am not sure that a lon-
ger lecture on the density of Titan’s
atmosphere or the hazards of add-
ing free oxygen to a methane mix
will help in this case.” The scientist
also mentioned the challenge of
“finding a photosynthetic bacteri-
um that produces oxygen at 94 kel-
vins [–290 degrees Fahrenheit].”
Then I heard from Donald Can-
field, a geoscientist at the Univer-
sity of Southern Denmark and au-
thor of the book Oxygen: A Four-
Billion-Year History. “As far as we
know,” Canfield wrote, “all life re-
quires water, so if we are looking
for life to thrive in something else,
we are pushing the boundaries
way beyond how we un der stand
life to function. Such a discovery
would be foundational but way beyond what we know about
life now. Prize money would be incidental to the Nobel Prize
that would follow.”
Did I mention that Earth’s sulfidic seas in the mid- to late-
Proterozoic eon are referred to as the Canfield Ocean, in honor
of his re search? Anyway, Canfield continued, “I think it might be
wiser to offer a prize to someone who could produce a photosyn-
thetic organism that could produce copious amounts of hydro-
gen for energy, or plastics, or some other useful hydrocarbon as
a substantial part of their metabolism.”
Because if we’re going to spitball ideas about designer microbes
that can help humanity, they might as well be good ones.JOIN THE CONVERSATION ONLINE
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How not to spend a lot of time
By Steve Mirsky
© 2020 Scientific American