To the layperson, a fly is just a fly. But to a scientist with a microscope, it's a coffin fly that can dig two meters to find decaying flesh in which to lay its eggs so that its offspring can feed on the putrid tissue. It prefers lean over fatty. It is literally found in coffins. Is this the stuff of nightmares or just another insect buzzing too close to your ear on a summer's night?
Consider the twisted-wing parasite, which grows by consuming its mother from the inside out. Or the shrunken-headed spider-stalking fly — its young penetrate a spider's body and then lay dormant until the spider is large enough to feed on, at which point the parasite “convinces” the spider to spin a death cocoon around its own body, and the feeding begins.
These macabre insects don't live in some far-off country; they live in L.A., amid the concrete, asphalt, Spanish colonials and hulking stucco apartment buildings. While scientists knew that these creatures — and many others — made their homes here, nobody had ever studied them in this most urban of environments.
Until now. The Natural History Museum's BioSCAN project and team, with a staff of seven experts — plus a rotating crop of interns, students, researchers and volunteers — is combing through what will likely be “hundreds of thousands if not millions” of insect specimens collected in the backyards of 30 L.A. residents during a three-year period.
Emily Hartop, the project's assistant collections manager, is lead author of the group's first paper, just published in the journal Zootaxa on April 2. It details the discovery in Los Angeles of 30 new insect species in a single genus, Megaselia, of the fly family Phoridae.
“We're dealing with so much material,” Hartop says. It can include hours just studying and drawing the details of fly genitalia — because that is often the only distinguishing feature among the species — or parsing the curve of a teeny-tiny appendage. The staff has gone through more than 10,000 specimens of the tiny phorid flies alone.
The projected new species numbers are staggering. Brian V. Brown, the museum's curator of entomology and BioSCAN principal investigator, says, “We expect there are 40,000 to 50,000” types of phorid flies in Los Angeles. Put in perspective, there are only about 4,000 currently described phorids, while known vertebrates (reptiles, amphibians, birds, fish, mammals) number about 64,000.
“If you look at an insect with the naked eye, it's a dot,” says Lisa Gonzalez, BioSCAN assistant collections manager and lifelong L.A. bug
nut. “But they're all beautiful, with all kinds of weird extensions.”
Insects caught in the traps set up in 30 selected backyards go beyond flies, although flies — specifically phorids — are a focus of BioSCAN. Everything from bees to butterflies gets caught in Malaise traps, which resemble small, netted tents, peaked on one end, leading to a collection bottle of life-ending ethanol.
To thank the 30 households scattered from Glendale to Gardena that have given up a slice of their backyards to accommodate the traps and a weather station, newly discovered phorid species are named after each family. Megaselia mikejohnsoni and M. rodriguezorum are among the monikers.
Brown, who sees L.A. not as an urban wasteland but as a “subtropical paradise for insects,” got the idea for this project after making a bet with a museum trustee that he could find a new species in an L.A. backyard.
“I get the impression that most people feel that discoveries need to be made in Suriname or Borneo, but the process of finding new insects is the same anywhere,” he says.
One could perhaps look for a discovery on the mild-mannered scientist's desk, littered with accoutrements of his trade: an unidentified fly in a plastic bag, a 125 million–year-old insect preserved in amber, a box of pinned flies, and — an interloper from the paleontology side of the museum — a triceratops meat chart coffee mug.
Early results of the BioSCAN study, which is still in its infancy, have surprised the researchers while also telling a unique story of the urban experience. Remember those coffin flies? In one backyard, the scientists couldn't figure out why so many were caught in a trap. Finally, the site host sheepishly admitted to burying family pets in the yard.
Another finding that may please urban dwellers: The team has collected just one type of cockroach, a forest dweller in a yard nearer to the mountains. Gonzalez says this is likely a reflection of how the traps work and not an absence of the unpopular creatures.
The team is interested in more than just counting, notating, pinning and filing specimens away. “We're looking at 'How does it fit into the larger picture?' — not just what there is and how many,” says Regina Wetzer, BioSCAN project co–primary investigator and director of the museum's Marine Biodiversity Center. “It's about thinking in larger terms — how it affects all of us.”
“A driving force behind the project is to really help us understand what it is about urbanism that's changing biodiversity,” adds Dean Pentcheff, BioSCAN's project coordinator, who has a background in marine biomechanics. “Without that knowledge, there's no way to save it.”
Pentcheff says there's no “value judgment” on L.A.'s urban culture. As L.A. Weekly has reported, New York University doctoral student Thomas Laidley has shown that Greater L.A. is so dense that, by his measure, it has the least sprawl of any U.S. metro area. L.A. doesn't skip and hop over the land, creating outposts in open spaces; it is fully crammed throughout.
The BioSCAN team wants to uncover which environments within this highly urban world encourage insect biodiversity. Is it better to create many small parks or just a few big ones in order to boost a biodiverse insect population? One question that hasn't yet been researched: Does insect diversity increase or decrease in relationship to different types of urban developments?
“People need to be around biodiversity,” Brown says. “We've got unique things in California that we want to encourage, and that's a message we can bring to the city and affect how it's planned or landscaped.”
Beyond the scientific import for the city and entomology at large, there's a sense of awe toward the insect world that permeates the BioSCAN team, and they hope they can pass it on to the general public.
“When I look into a microscope, I'm looking into another universe that most people never get to see,” Gonzalez says. “It's almost a mystical experience.”
“It does kind of ruin large vertebrates for you,” jokes Wetzer, who refers to her time spent looking at magnified bugs as a “petri dish safari.”
The staff has been educating the public inside the Natural History Museum's Nature Lab, which focuses on L.A.'s plants and animals. Visitors can watch at a microscope station as the staff sorts and identifies insects.
There on one occasion Brown pointed out a fire ant–decapitating fly found in Glendale, which lives up to its name by planting its egg in the thorax of a never-the-wiser ant. Once the larva develops, it moves to the ant's head, where it molts. It's only when the maggot begins to eat away at the inner head tissue that the ant starts to behave oddly. Once the ant dies, its head falls off and the fully formed fly emerges from its remains.
As Gonzalez puts it, “The things you read about in science fiction books — that happens in the real world.”