11.2019 | THE SCIENTIST 15idea, although he cautions that Görres
and Chesmore have yet to attempt to
detect stridulations beyond their con-
trolled lab experiment and have not yet
demonstrated that it’s possible to accu-
rately estimate the abundance of larvae
from the frequency of their stridulations.
In addition, Görres wants to record
and analyze stridulation sounds in order
to improve estimates of insect biodiversity.
As part of her upcoming Underground
Twitter study, which aims to determine
when and why insects in the soil commu-
nicate with one another, she plans to bury
multiple microphones in a field to record
around the clock for six months. “There
are all these insect studies about how bio-
mass is dropping and species are endan-
gered, but these are all about insects above
the soil,” she says. “We don’t know much
about biodiversity in the soil because
it’s so hard to monitor.” Mankin agrees,
although he notes that because many soil
insects aren’t known to stridulate, relying
on stridulations alone could also skew esti-
mates of insect diversity.Another hurdle in moving acoustic
monitoring from the lab to the field is
how to deal with the sheer quantity of
data the approach generates. For the lab
study, the researchers manually ana-
lyzed all of the recordings they made—
about 12 hours’ worth of audio—by lis-
tening for the occasional stridulation
and deciding which sounds belonged
to which species. “This is the one dis-
advantage of audio recording,” Görres
says. “It produces so much data, at
[some] point you cannot analyze it
manually anymore.” However, she says
she’s confident that automated data
analysis, perhaps enabled by machine
learning, will be able to pick out stridu-
lations from the recordings and identifywhich sounds belong to which species in
a matter of hours.
Ultimately, Görres hopes to return
to the questions about greenhouse
gas emissions that she initially set
out to answer. “My hypothesis is that
the acoustic activity [of white grubs]
somehow relates to their metabolic
activity,” she says, “so maybe I can use
acoustic activity to model greenhouse
gas emissions. But right now, it’s just a
crazy idea of mine.”
—Michael GrawMurderous
Minds
Kent Kiehl and his research team regu-
larly park their long, white trailer just
outside the doors of maximum-security
prisons across the US. Inside the vehi-
cle sits the bulky body of a mobile
MRI machine. During each visit, peo-
ple from the prison make their way to
and from the vehicle in hourly shifts to
have their brains scanned and help
to answer an age-old question: What
makes a murderer?
“It’s not an uncommon thing for
[incarcerated people], while they’re
getting a scan, to be like, ‘I’ve always
been different. Can you tell me why I’ve
always been so different?’” says Kiehl, a
neuroscientist at the University of New
Mexico and the Albuquerque-based non-profit Mind Research Network (MRN)
who helped design the mobile MRI sys-
tem back in the early 2000s.
The author of The Psychopath Whis-
perer: The Science of Those Without a
Conscience, Kiehl has been fascinated
by the criminal mind since he was an
undergraduate at the University of
California, Davis. Now, as director of
mobile imaging at MRN, he oversees
efforts to gather brain scans from thou-
sands of people held in US prisons to
learn what features, if a ny, might differ
from scans of the general population.
This massive dataset recently
allowed Kiehl to examine the brain
structures of more than 800 men held
in state prisons in New Mexico and
Wisconsin in an attempt to distinguish
incarcerated people who have commit-
ted homicide from those who have com-
mitted other crimes.
First, Kiehl and his colleagues labo-
riously sorted the pool of people who
had volunteered for the study into
three categories based on their crimes:
homicide, violent offenses that were not
homicide, or non-violent or minimally
violent transgressions. The team relied
on official convictions, self-reported
homicides, and confidential interviews
with participants to determine whoHe said, “Oh my god, those
are stridulations.” We didn’t
expect that at all.
—Carolyn-Monika Görres
Hochschule Geisenheim University
SCAN-MOBILE: Kiehl and his colleagues made
more than 75 modifications to a trailer and the
MRI system inside to outfit both for the team’s
unique research.KENT KIEHL