72 Scientific American, February 2022
RECOMMENDED
Edited by Amy Brady
Illustration by London LaddOtherlands:
Journeys in
Earth’s Extinct
Ecosystems
by Thomas Halliday.
Random House,
2022 ($28.99)As a teenager, I was obsessed with dino
saurs, but I had little aptitude for what came
before them. I couldn’t make sense of what
John McPhee, in that most glorious line of
geopoetry, called “deep time.” Planet Earth
is 4.5 billion years old, and life has been
around for about 90 percent of it. When
T. rex stalked its prey, every trilobite that
ever fossilized was already in the ground.
Every Brontosaurus , too. The time spans
seem inconceivable, yesterday’s worlds
far too distant from our own. Then, a book
made it click: this was Richard Fortey’s
1997 Life , which I devoured around the time
I started studying geology in college. It was
hard science, but it read like a novel, and
it made the murky depths of prehistory into
a riotous story.
Fortey wrote from his perch at the
Natural History Museum in London, as one
of the world’s most respected and expe
rienced paleontologists, the letters F.R.S.
(Fellow of the Royal Society) trailing his
name. A quarter of a century later Fortey’s
Life has a worthy successor in Thomas Hal
liday’s Otherlands. Writing with gusto and
bravado, Halliday is part of our gen eration
of 30something paleontol ogists, not long
out of grad school, putting a millennial spin
on popular science writing.
In a genre that can tend toward cook
iecutter sameness ( another dinosaur
ency clopedia?), Halliday has honed
a unique voice. His approach is novel as
well. Otherlands is a Benjamin Button tale,
which begins in the present day and runs
in reverse, the evolution of life in rewind.
He structures the narrative through an
ecological lens: Each major division of geo
logic time is given a single chapter, which
is focused on a single lost ecosystem. As
you read along, Earth gets weirder and
weirder, the creatures more alien, more
removed from the norms and comforts
of today. Soon enough, you find yourself
underwater 550 million years ago, in what
is now Australia, where fish and whales
and corals are nothing but a future fantasy,
as blobs of primitive cells leave ghostly im
pressions on the seafloor.
Otherlands is a verbal feast. You feel like
you are there on the Mammoth Steppe,
some 20,000 years ago, as frigid winds blow
off the glacial front. You sense fear in a band
of human ancestors as they clamber up
a tree, fleeing a python. You can taste
the salty air over a Jurassic lagoon and com
miserate with a gorgonopsian—a ghastly
mammal predecessor—as a tumor presses
down on its jaw.
Along the way, we learn astounding
facts. Some trees that are alive today
emerged from seeds while mammoths
trudged through snow; reefs of sponges
once stretched from Poland to Oklahoma.
And we meet some sublime creatures.
There’s Haikouichthys , one of the oldest fishes, “only a few centimeters long, shaped
like a fallen leaf.” Even more ancient is Eo-
andromeda , probably one of the oldest ani
mals (or maybe not), a “coiling helterskel
ter, floating hypnotically” in the Precam
brian oceans. My favorite, the official fossil
of my home state of Illinois, is the mystify
ing Tully Monster, with its “segmented tor
pedo of a body” and a “hose of a vacuum
cleaner” as a nose.
During this backwards journey across
time, Halliday centers his tale on how spe
cies work together as ecosystems and food
webs. Yes, dinosaurs and megafaunal mam
mals pop up throughout, but plants, bugs,
mush rooms and deepsea bacteria all get
their due. The great calamities and
transforma tions of prehistory are treated
more like background; the endPermian
mass ex tinction—the closest complex life
has ever come to annihilation—garners a
single paragraph, and the origin of limbed
tetra pods from finned fish takes all of four
sen tences. This keeps attention on the big
ger picture, as Halliday shows that the same
rules of energy flow have governed all eco
systems over time, linking that dream world
of 550 million years ago to dinosaurs to our
fragile Earth of today.
Otherlands is a book for people who like
books. Chapters begin with verses and prov
erbs in many languages (original and trans
lated), poetry and mythology are liberally
quoted throughout, and fossils are described
with comparisons to Gaudí’s architecture
and L. S. Lowry’s paintings. In many ways,
it is more literature than tradi tion al popular
science, which makes me wonder how it will
connect with people who haven’t studied
science (or poetry) since school.
Another new book on evolutionary his
tory is more tailormade for a general audi
ence. A (Very) Short History of Life on Earth ,
written by Nature editor Henry Gee and
published in late 2021, does what it promis
es. Punchy and breezy, his book reads like a
bedtime story, the triumphs and cata clysms
of life waltzing by at breakneck speed. Gee’s
book is more appetizer, Halliday’s is more
main course, and to gether they weave an
evocative tapestry of what Earth and life
have endured—which helps us understand
where we are going next.Steve Brusatte is a professor of paleontol
ogy at the University of Edinburgh.NONFICTION
Life, Linked
A reverse journey through geologic time shows
the interconnectedness of Earth’s species
Review by Steve Brusatte