the Australian Animal Health Labora-
tory, and at the highest biosecurity level—
BSL-4—there are vials of some of the
nastiest animal-borne pathogens on the
planet, including Ebola. (The labora-
tory gets a shout-out in the movie “Con-
tagion.”) Staff members who work in
BSL-4 units can’t wear their own clothes
into the lab and have to shower for at
least three minutes before heading home.
The animals at the facility, for their part,
can’t leave at all. “Their only way out is
through the incinerator” is how one em-
ployee put it to me.
About a year ago, not long before the
pandemic began, I paid a visit to the
center, which is an hour southwest of
Melbourne. The draw was an experi-
ment on a species of giant toad known
familiarly as the cane toad. The toad was
introduced to Australia as an agent of
pest control, but it promptly got out of
control itself, producing an ecological
disaster. Researchers at the A.C.D.P.
were hoping to put the toad back in the
bottle, as it were, using CRISPR.
A molecular biologist named Mark
Tizard, who was in charge of the proj-
ect, had agreed to show me around. Tiz-
ard is a slight man with a fringe of white
hair and twinkling blue eyes. Like many
of the scientists I met in Australia, he’s
from somewhere else—in his case, En-
gland. Before getting into amphibians,
Tizard worked mostly on poultry. Sev-
eral years ago, he and some colleagues
at the center inserted a jellyfish gene
into a hen. This gene, similar to the one
I was planning to plug into my yeast,
encodes a fluorescent protein. A chicken
in possession of it will, as a consequence,
emit an eerie glow under UV light. Next,
Tizard figured out a way to insert the
fluorescence gene so that it would be
passed down to male offspring only. The
result is a hen whose chicks can be sexed
while they’re still in their shells.
Tizard knows that many people are
freaked out by genetically modified or-
ganisms. They find the idea of eating
them repugnant, and of releasing them
into the world anathema. Though he’s
no provocateur, he, like Zayner, believes
that such people are looking at things
all wrong. “We have chickens that glow
green,” Tizard told me. “And so we have
school groups that come, and when they
see the green chicken, you know, some
of the kids go, ‘Oh, that’s really cool.
Hey, if I eat that chicken, will I turn
green?’ And I’m, like, ‘You eat chicken
already, right? Have you grown feath-
ers and a beak?’”
Anyway, according to Tizard, it’s too
late to be worried about a few genes
here and there. “If you look at a native
Australian environment, you see euca-
lyptus trees, koalas, kookaburras, what-
ever,” he said. “If I look at it, as a scien-
tist, what I’m seeing is multiple copies
of the eucalyptus genome, multiple cop-
ies of the koala genome, and so on. And
these genomes are interacting with each
other. Then, all of a sudden, ploomph,
you put an additional genome in there—
the cane-toad genome. It was never
there before, and its interaction with all
these other genomes is catastrophic. It
takes other genomes out completely.”
He went on, “What people are not see-ing is that this is already a genetically
modified environment.” Invasive spe-
cies alter the environment by adding
entire creatures that don’t belong. Ge-
netic engineers, by contrast, just alter a
few stretches of DNA here and there.
“What we’re doing is potentially
adding maybe ten more genes onto
the twenty thousand toad genes that
shouldn’t be there in the first place, and
those ten will sabotage the rest and take
them out of the system and so restore
balance,” Tizard said. “The classic thing
people say with molecular biology is:
Are you playing God? Well, no. We are
using our understanding of biological
processes to see if we can benefit a sys-
tem that is in trauma.”F
ormally known as Rhinella marina,
cane toads are a splotchy brown,
with thick limbs and bumpy skin. De-
scriptions inevitably emphasize their
size. “Rhinella marina is an enormous,
warty bufonid (true toad),” the U.S. Fish
and Wildlife Service notes. The U.S.
Geological Survey observes that “large
individuals sitting on roadways are eas-
ily mistaken for boulders.” The biggest
cane toad ever recorded was fifteen inches
long and weighed six pounds—as much
as a chubby chihuahua. A toad named
Big Bette, who lived at the Queensland
Museum, in Brisbane, in the nineteen-
eighties, was nine and a half inches long
and almost as wide—about the size of
a dinner plate. The toads will eat almost
anything they can fit in their oversized
mouths, including mice, dog food, and
other cane toads.
Cane toads are native to South Amer-
ica, Central America, and the southern-
most tip of Texas. In the mid-eighteen-
hundreds, they were brought to the
Caribbean. The idea was to enlist the
toads in the battle against beetle grubs,
which were plaguing the region’s cash
crop, sugar cane. (Sugar cane, too, is an
import; it is native to New Guinea.)
From the Caribbean, the toads were
shipped to Hawaii. In 1935, a hundred
and two toads were loaded onto a steamer
in Honolulu, headed for Australia. A
hundred and one survived the journey
and ended up at a research station in
sugar-cane country, in northeast Queens-
land. Within a year, they’d produced
more than 1.5 million eggs. (A female
“It’s not that I can’t stand the cold—I just hate the holidays.” cane toad can produce up to thirty thou-