Scientific American - USA (2021-03)

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14 Scientific American, March 2021

ing. But of all the widely studied “model
species” that are easy to raise in the labo-
ratory, rodents such as mice have been
most instrumental in understanding how
the brain works.
“The advantage of the mouse is that its
brain is remarkably similar to the human
brain, whereas the advantage of the octo-
pus is that it’s remarkably dissimilar,” says
Gül Dölen, a neuroscientist at Johns
Hopkins University. Comparing and con-
trasting these systems with our own, she
says, “gives you that logical power of
reduction.” Nematodes and fruit flies are
also very dissimilar to humans, she notes,
but octopuses eclipse these fellow inverte-
brates in terms of complexity. Recognizing
the unique opportunity cephalopods pro-
vide as vastly different yet highly sophisti-
cated creatures, Dölen and other neurosci-
entists are rooting for them to become the
field’s newest model organism.
Using octopuses to gain insight into
our own species was originally proposed
in the 1960s by neurophysiologist J. Z.
Young. The idea moved within reach in
2015, when scientists sequenced the first

octopus genome, for the California two-
spot octopus. “A whole genome opens
up huge levels of information you didn’t
have before,” says Clifton Ragsdale, a neu-
robiologist at the University of Chicago,
who co-authored the octopus genome
study in Nature.
As was the case with other model spe-
cies, publishing the octopus genome paved
the way for critical modes of investigation,
the researchers say. These include using
genetic engineering to probe how the
brain works, zooming in on where specific
genes are expressed, and exploring evolu-
tion by calculating differences between
octopus genes and those of other species.
“We’re at a really exciting moment for
working with these remarkable animals,”
says Caroline Albertin, an evolutionary
developmental biologist at the Marine Bio-
logical Laboratory in Woods Hole, Mass.,
and lead author of the genome study.
“There’s just a vast ocean of research and
questions that we need to explore.”
Toward that end, researchers have
begun developing cephalopod versions of
the same molecular tools that those work-

ing with mice or flies take for granted. Last
summer in Current Biology, Albertin and
her colleagues described the first cephalo-
pod gene knockout (inactivating a gene to
study what it does). Now the same team is
working on gene knock-ins that will, for
example, let scientists insert activity indi-
cators into octopus cells. This process will
let them study the animals’ neural activity
in real time, says Marine Biological Labo-
ratory researcher Joshua Rosenthal, who
co-authored the knockout study. “Once
we get that next step,” he says, “I think the
community is just going to start exploding.”
Research is already accelerating. In 2018
Dölen and co-author Eric Edsinger dosed
octopuses with MDMA and found that
although they are typically antisocial, they
respond to a drug-induced flood of the
neurotransmitter serotonin the same way
humans do: they relax and become more
sociable. Through genome analysis, the sci-
entists also confirmed that octopuses pos-
sess the same serotonin transporters that
MDMA binds to in vertebrates. As report-
ed in Current Biology, this finding suggests
that sociality could involve a molecular




A new algorithm could
spot the insect’s eggs and
curtail their rapid spread

Since it was first noticed in 2014 in Berks
County, Pennsylvania, the spotted lantern-
fly—a one-inch-long plant hopper that
resembles a moth and is native to China—
has been wreaking havoc on East Coast
lumber, tree fruit and wine industries. It has
spread to many counties in Pennsylvania,
plus parts of New Jersey, Delaware, Mary-
land, Virginia, West Virginia and New York.
The invasive, plant-killing insect can lay
its eggs on almost any surface, including
vehicle exteriors. These egg masses “are
most concerning because they can go very
far, by hitchhiking,” says Maureen Tang, a
chemical and biological engineer at Drexel
University. Tang’s new project uses crowd-
sourced photographs of the egg masses to

The spotted lanternfly is proliferating
quickly across the U.S. East Coast.
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