On NOVA Next: Stereotype Threat and Biased Testing

The good folks at NOVA Next were good enough to publish my article on a new social psychology experiment. Stereotype threat is when someone fears they are at risk of confirming a negative stereotype about their group. It helps explain why women and ethnic minority students underperform on standardized exams that begin by asking for your sex and ethnicity. The researchers I spoke to found that stereotype threat's effect can be reversed under certain conditions, though.

Reporting on Brain Implants for Depression

from WIkimedia Commons, user Andreashorn.

Right now my classmates and I are focusing on how to write a science news article. My first go at this can be found on Scopeweb, which is our program's online publication. It involved diving into research on using deep brain stimulation, a treatment involving a small electrode implanted in the brain, to treat depression. It was fascinating to learn about an area of medical research in which doctors do not agree on where to take the research next, and I'll be interested to follow the story as it evolves. 

You Can't Build a Better Tuna

RoboTuna

Here's the first short essay I wrote for the Science Writing program at MIT. As a warm-up exercise, we were tasked with observing an object at a local museum and writing 500-800 words on it.

Though over twenty years old, RoboTuna looks like a freshly caught fish partway through filleting.

Its fabric skin is pulled back to reveal slender plastic ribs and motor-guts near its head, but the layer of synthetic scales between ribs and skin still clings to its back half. A wire threads through each belt of long, thin scales, creating a series of overlapping scale-belts down its body. Six joints down its spine give it the potential to ripple like a tuna hurtling after prey. RoboTuna is ready to swim as smoothly as a real fish.

Drones for Watching Beavers and Whales?

Are drones capable of non-evil purposes? Actually, are they even capable of a use that doesn’t make them look creepy and intrusive? (I feel that drone engineers need to do more to make drones that don’t instantly remind me of the Viper probe droid that the Imperial Fleet sent to spy on the Rebel base on planet Hoth.)

There is a surprising application for robotic aircraft that gives me a teaspoonful of hope. In a paper in the Journal of Unmanned Vehicle Systems (a journal whose title will always sound creepy to me) four researchers describe how they used a drone to survey the impacts of a pair of reintroduced beavers on ecosystem structure.

Photo by Per Harald Olsen

Conservationists in the United Kingdom are engaged in a major project of reintroducing the beaver to their country. Overhunting forced the species to local extinction as early as the 16th century. By damming streams and creating ponds and wetlands, beavers make a huge contribution to local diversity. Amphibians, fish, arthropods, plants and more all depend on the habitat created by beavers.

This study observed a pair of beavers brought to a first-order stream in southwestern England. The drone, a hexacopter equipped with a camera, was able to provide good images of beaver activity such as gnawed trees and dams under construction. And with software, the researchers converted these photos to computer models capable of telling us about hydrology, topography, vegetation structure, and other interesting landscape variables.

Unfortunately, the researchers only studied this site after the beavers had done their work, so they weren’t able to make comparisons to how the site was before the beaver engineers got to work.

Nonetheless, what the study suggests will be possible soon is very promising. The drone method is not just trendy. It’s cheaper than piloted aircraft, and, since it is low-altitude, it provides higher resolution data. It’s less labor intensive and faster than doing surveys on foot. You also avoid disturbing sensitive wetlands, which can be harmed by trace amounts of chemicals or pathogens found on researchers. The wildlife themselves are less bothered by a quiet hexacopter than a human or a piloted helicopter. And though the study didn’t mention it, a programmable aircraft is more rigorous than a human observer. Human estimations of vegetation parameters is notoriously prone to error.

Lastly, the drones don’t have a social schedule or a preference for warm or cold weather, and can be kept to inhumane and demanding survey schedules that even a seasoned field biologist would reject.

Another study in the same issue showed perhaps even more exciting benefits to drone surveys of whales. The surveyors launched the hexacopter from small craft at sea, where piloted aircraft would have been expensive and unfeasible. Since the whale pod showed no behavioral changes, the paper concluded that the drone did not bother them. From a height of 35 meters, the drone’s images showed enough detail for the biologists to identify each whale by its markings. And, because the drones can be kept to a constant altitude, biologists can use their photos of whales to calculate precise sizes and track growth rates for each whale.

I would be sad if the advent of drone ecology would mean the disappearance of human-led field surveys. We probably don’t have to worry about that any time soon. The main thing is to celebrate that we have found a socially and environmentally beneficial use for at least a few of those freaky airborne robots.

Egrets at Columbia Bottoms

This morning, my mom and I drove to Columbia Bottom Conservation Area for the my last birding trip in the St. Louis region for a while. Just north of the city, stacks of shipping containers and freight warehouses transition in just a few miles to the broad floodplains of the confluence of the Mississippi and Missouri rivers.  I had never been to the park before, and was impressed with the shorebird, wading bird, and duck diversity that the broad wet meadows and mudflats support. 

After spotting  a few Killdeer and Lesser Yellowlegs foraging in a roadside puddle, we were impressed with a flock of over 200 Great Egrets packed in the tall grasses of a marsh.

Neither of us had seen so many egrets in one place before. We set up a scope to get a closer look and see if any Snowy Egrets were tucked in among the others. (They would have black bills rather than orange.) We didn't see any Snowies, but there were at least two Great Blue Herons strutting around the edges of the flock. You can get a fairly high resolution picture by pressing a camera phone up to a spotting scope, though this picture isn't the best example.

We spooked a few Egrets as we drove by. 

Looking to the other side of the road, we saw a large lake lined with a seemingly endless flock of egrets, at least twice as large as the ones nearer to us. You can see them in the distance of this photo as a line of white on the far side of the lake.

We also found a flock of 150+ ducks beside a smaller group of egrets. In their duller non-breeding plumage, they gave us some trouble in identification, but seeing the band of white on the underside of their wings, dark eyestripe, and blotch of white behind the beak (the last two aren't so easy to see in this picture) allowed us to identify them as Blue-winged Teals. 

We followed the road until it took us to the Missisippi River. An Army Corps of Engineers pumping station had a large scale for reading the flood level. Strange to think that those heights are plausible; the bank in this photo is already 15 feet above the water level. 

Over the last two centuries, engineering projects in general have sought to contain rivers and eliminate floodplains so that they can be settled for homes and farming. The path of the Missouri through the plains used to change drastically year to year as snowmelt and spring rains sprung the river from its banks, reshaping its embankments each season. Millions of amphibians spawned in the huge wetlands created in the thaws, and amphibian predators like the egrets followed in the summer. At Columbia Bottom, the Army Corps of Engineers and the Missouri Department of Conservation have collaborated to restore and protect over 4000 acres of floodplain, allowing us to see a sizable glimpse of an ecosystem type that once stretched for hundreds of miles. 

Selfishness and Sushi

Yesterday morning a downpour started, so I stepped out to the covered porch and read about sushi. I had Trevor Corson’s book, The Zen of Fish, which uses an American woman’s entry to the California Sushi Academy to explore the history and current state of sushi culture.

“In the mid-1990s, Reiko Yuyama, a Japanese publishing executive, stopped by a famous sushi bar for a meal. She was alone. Most of the other customers were men. The chef chatted amiably with the other customers but ignored Yuyama. She managed to order several pieces of sushi, but after only her fourth piece a cup of green tea appeared in front of her. Since green tea is often served at the end of the meal, she took this as a request that she leave. She stayed for an hour, continuing to order. When she asked for the bill, it was obviously for more than she’d been served.

“Spurred by this incident, Yuyama visited many of the best sushi bars in Tokyo and around Japan, always alone, and described her experiences in a book called One Woman Sushi. Traditional sushi bars are like exclusive clubs, Yuyama found—difficult for single women and the uninitiated to enter, especially since there are no menus.

“The other women Yuyama encountered in the sushi bars were almost always accompanied by men, and the men used the opportunity to impress their dates with ostentatious displays of sushi knowledge. …. When Yuyama ordered sushi herself, the other women glared at her. Yuyama concluded that traditional sushi bars are the last place in Japan where men still feel completely superior to women.”

This came as a surprise to me. Stepping into a fairly Westernized sushi shop in Missouri, I had no idea the role that gender played in this kind of cuisine. I suspected that California rolls weren’t traditionally enjoyed in Japan. Corson confirmed this, but also described how Japanese tourists in America sometimes order the greasier American sushi dishes they can’t get back home. Cultural legacies, adaptations, and power struggles all acted themselves out in the apparently undramatic space of a sushi bar. Reading Corson, as with his previous book, The Secret Life of Lobsters, is a trail of unexpected revelations about apparently commonplace items. So it is too with other nonfiction writers—David Foster Wallace’s essay “Consider the Lobster” and John McPhee’s book Oranges come to mind.

Is it selfish to write about sushi? About fine food in general, when people are starving, no less? Thoughts like this bring me to Doctor Zhivago—the scene in which the narrator, a Bolshevik commissar, comes to warn his brother Yuri, the poet-doctor protagonist, that his apolitical lyric poetry was putting “a noose round his neck,” in the eyes of the revolutionary authorities. Yuri asks his brother, “Do you think it’s ‘personal, petit-bourgeois and self-indulgent?’” The narrator says “I lied” on the voice-over as his past self nods to Yuri. But fine feelings aside, people were and are starving.

The short answer: yes, it’s selfish—in the same sense that it’s selfish to discuss the shortcomings of Western medicine when people go without basic services elsewhere. However we angle it, we are all trapped in a web of privilege and injustice.

However, what allows us to see this web, and therefore, do something about it? For me, it’s books.

The goal of great fiction is not only to give someone an in-depth knowledge of Russian aristocratic drawing-room conventions, the conditions of a Harlem tenement in the Depression, or the legal details of inheritance in southern England, but instead to develop a reader’s ability to think critically about the human motives that created all of these social structures. No, we don’t improve the world at large a whit by knowing who the Thane of Cawdor was, but we might by being able to spot someone like him, willing to murder to become the next King of Scotland.

In The Zen of Fish, Corson follows two chefs, Zoran and Tetsu, from the restaurant Hama Hermosa, in their morning trip to Los Angeles’s biggest fish market, International Marine Products.

“As they walked through a loading door in the warehouse, they felt the chill of the huge refrigerated space. The smell of the ocean assaulted their nostrils. Their shoes squished over a film of frigid water on the plastic floor. Under a high ceiling, long tables were covered with plastic bins and Styrofoam boxes full of ice. Zoran nodded to Tetsu and the two men split up. … Shouts in Spanish and Japanese filled the room. … Zoran eyed the bins. There were sardines, squid, and barracuda from the waters of California. There were butterfish, tilefish, skate, and live Maine lobster from the East Coast. There were amberjack, grouper, and trevally from Australia and New Zealand. From Japan there were Pacific saury, blue snapper, red gurnard, largehead hairtail, chicken grunt, and many other fish that didn’t even have English names.”

Some nigiri and sushi rolls I had recently.

Connected to a piece of nigiri on a plate in California, despite centuries of innovation, is still a deep knowledge of the sea—where fish come from, their diet, their ecology, how these things shape their taste. Studying that plate, tugging on its connections, Carson finds not just into a consideration of sushi culture but an entire world of human labor, knowledge, ambition, and sense of fun that sustains it.

It’s fair to question the motives of a writer who’s writing about something they love—Trevor Corson and his sushi, John McPhee and his rocks—because such a project can be deeply rewarding work. (As well as exhausting.) But it’s not fair to question them and then keep eating sushi unreflectively.

Maybe if we thought deeply enough about our own food we would notice those who don’t have any for longer than a few seconds. Maybe if we considered the energy expended in transporting fresh fish from New Zealand to the U.S., we would think more critically about the possibility of feeding distant nations stricken by famine. At the least, maybe we would appreciate people who make our sushi more completely, with a greater understanding of the training and effort it takes to make something worth eating.

Of Swallow Wings and SUV Windshields

I often think of high-rise buildings, subways, and dams when I think about characteristic human changes to the landscape. But in terms of acreage, high-input agricultural zones have been a more widespread and comprehensive land use change in the past two centuries. This land use type includes not just the actual cornfields but also the houses, grain elevators, country highways, and small towns that support the farming. The cumulative effect has been to almost wipe out grasslands worldwide, replacing them with an ecosystem with many different pressures and opportunities than the previous one.

These changes have measurable impacts on wildlife that are often surprising. Wild populations do not merely shuffle out of the way when humans come to settle. It is always a collision. Some are killed in droves like the American buffalo. Others slowly or steadily decline over many years, like grassland songbirds. And a few special species are able to adapt and thrive in the new ecosystem.

Photo by Don DeBold

Cliff Swallows are small, handsome flycatching birds with a blue back and wings, a white belly and a red throat. They create colonies of nests on vertical surfaces made from mud they carry in their beaks. In Nebraska, biologists have been studying the habits of Cliff Swallows for over 30 years. There, the birds are not nesting on natural cliffs but the constructed ones under highway overpasses and roadway culverts. Birds with shorter wings are better able to avoid passing cars, and short wings are now the norm in these cliff swallow populations, according to Charles Brown and Mary Bomberger Brown of U. Nebraska-Lincoln and U. Tulsa. They described their findings in a paper, “Where has all the road kill gone?” published in Current Biology in 2013.

Brown and Brown compared the roadkilled birds to a sample of birds which died accidentally while the researchers used mist-netting to capture individuals for study. They saw that the roadkilled birds almost all had longer wings than the rest of the population. Over the 30-year study, fewer and fewer birds ended up on the highway shoulder, and the general population’s wings got shorter.

To understand why short wings help you dodge a Hummer, we have to consider flight physics. Longer wings lead to efficient flight and shallow, graceful takeoffs by decreasing the amount of bird mass carried by each square inch of wing. But shorter, stubbier wings allow for greater maneuverability and more vertical takeoffs. These sharply angled takeoffs, the researchers believe, are what allowed the short-winged swallows to launch away from the road surface as a car approaches more successfully than their long-winged relatives.

While the outcome has a strange beauty, the process was plainly brutal. The selection pressure was millions of unforgiving windshields. Roadway traffic kills 80 million birds a year in the U.S. alone. If you look at Brown and Brown’s figures, you’ll see that even in a moderate year, they and their students collected tens of thousands of cliff swallow corpses. And these were the cliff swallow casualties only in their Nebraska study area. Not that the butcher’s bill here is so different from that resulting from other kinds of selective pressures. Evolution works through death—new forms arise because less successful individuals die.

Yet even though we can read the cliff swallow’s story as a success of natural selection, what stands out to me is how few species have been able to adapt this well. In the same region, birds such as Henslow’s Sparrow, the Upland Sandpiper, and the Greater Prairie Chicken have faced severe declines due to the loss and fragmentation of even marginally suitable habitat. For these birds, evolution would not be a matter of changing wing length but changing their entire lifestyle, something that is probably impossible within timescales meaningful to humans. Are the opportunities that one country highway creates for Cliff Swallows balanced by the splintering of the remaining lands for declining and endangered species?

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Citation

Brown, C.R., and M.B. Brown. 2013. Where has all the road kill gone? Current Biology 23:233-234.