Written by Jessica Portner
Photo by Edgar Chamorro
NHM Entomology Curator Brian
Brown will pursue flies at all costs.
During a recent expedition to the
Costa Rican cloud forest, Dr. Brown
offered himself up as bait for
mosquitoes in a region where one
species at least—
carries dengue fever. He reached
into the nest of biting leafcutter ants
and scooped out a handful to find
the flies that feed there and plucked
flies from a stingless bee nest—all in
a jungle home to several species of
“This is certainly nothing
compared to past centuries of field
research,” said Dr. Brown, back
at NHM. His predecessors would
run out of food on river trips and
encounter unknown diseases, he said.
“Our small discomforts are worth
discovering something extraordinary.”
Dr. Brown, along with a team of
Costa Rican collaborators and an
international, 40-member crew of
fly specialists, believe it will be.
The landmark three-year research
project, led by NHM and funded by
a National Science Foundation grant,
is one of the biggest inventories of
, or true flies, ever conducted
to estimate tropical biodiversity.
There are more than 160,000 species
of true flies worldwide, more than
all the better-known mammals,
birds, fish, reptiles, and amphibians
put together, but we know little
about them. Flies pollinate plants
we rely on for food. They decompose
waste and prey on pests. Tracking
fly populations and their environment
can shed light on climate change.
While their work has global reach,
these fly catchers operate in a limited
range—a 5-acre site (about three
football fields) in the foothills of
the tropical cloud forest in eastern
Costa Rica called Zurquí de Moravia.
Their techniques include catching
bats and birds and inspecting them
for flies, using fruit as bait, setting up
ultraviolet night lighting, and sweeping
with nets. In two weeks of days and
nights, they collected about 500
specimens, many new to science,
with unusual mating behaviors and
talents for mimicry. Dr. Brown said
you don’t have to brave a tropical
forest to discover cool bugs. Visitors
to NHM’s hands-on Nature Lab can
inspect insects under a microscope.
They can go on Bug Hunts in the new
Nature Gardens, and embark on an
urban expedition outdoors every day
In the FieldWith
NHM’s Fly Catchers
Learn more about the
project at phorid.net/zadbi.
Watch videos on YouTube at NHMLA.
Peek into a microscope in the Nature Lab
and see the insects we’ve caught in the