Scientists don’t necessarily spend all of their time at the lab bench. There are the intrepid, the brave, the field scientists. Those who don chest waders, snake gaiters, or snow shoes and venture out into the untamed wilderness, the carefully maintained nature preserve, or highly-trafficked urban park in pursuit of their science.
When you are outside of the lab, things can get messy. A common denominator of all fieldwork is that difficult problems seem to always arise. Difficult problems require creative solutions. Field scientists have devised many methods to collect data and specimens through the years. Some of these methods are a bit more unique than others. While those familiar with them may not bat an eye, to others, these outside-the-box methods can be endlessly interesting and entertaining.
Resourcefulness is a common thread among good scientists. Barry Cael, a graduate student in Oceanography at MIT, was intrigued by the geometric patterns he noticed in the mud of a receding tidal pool in Maine. He enlisted the aid of fellow colleagues Kelsey Bisson and Bennett Lambert to study the phenomena to see if the patterns were in fact fractals—clusters following a power law distribution. Similar patterns have been found in lake distributions. Lacking access to an aerial drone to photograph the patterns, Cael and his group resorted to suspending an iPhone from balloons to take aerial photographs then calibrating the pixel size using foam pool noodles as references. Ultimately, the group ended up supporting the iPhone on a long piece of PVC pipe, then using time-lapse photography to acquire their data. (Read the full paper in Physical Review E).
Trees can grow pretty tall. While the coastal redwoods of California can approach heights of 100 meters, they are not the only giants of the forest–many other species such as the mountain ash of Australia or the mengaris of the rainforests of Indonesia and Borneo can exceed 80 meters or greater. But if what you are interested in is studying the leaf chemistry of even your average oak tree, well, how do you get to those leaves at the top of that tree? It is often not possible to bring a scissor lift out to the middle of the forest, nor are most field ecologists expert tree climbers (though I am sure there are quite a few who are). To solve this problem, researchers have established a tried-and-true method that is not only quick, but efficient and cost-effective. Just shoot the leaves out of the tree.
Now granted, there are subtleties here. The preferred method is to use a shotgun to aim for the branch above the leaves you actually want. Leaves riddled with birdshot are not the most useful for analysis. A shot is fired, the branch is severed, and a portion of the branch with the leaves attached floats to the ground where it can easily be picked up. Shotgun sampling is a well-established technique that often brings surprise to those who learn about it for the first time, and may be also the only ecological method parodied in The Onion.
While shooting down leaves and using your cell phone to reenact scenes from Up are perfectly “odd,” the science seems to really hit the fan when we look at the lengths researchers have to go to when working in the animal kingdom. In order to study animals, you first have to “attract” them.
A couple of years ago I had the fortune to work with a Jorge, an undergraduate student from the University of Puerto Rico-Mayagüez as part of the Research Experiences for Undergraduates (REU) program at the Blandy Experimental Farm. Jorge introduced me to what I thought at the time was a remarkably strange method of collecting earthworms. He hammered a 25 x 25 cm metal frame into the ground then poured a mixture of deionized water and hot mustard powder on the ground within the frame. Admittedly, I was skeptical, but lo and behold earthworms soon began to emerge from the ground where Jorge expertly collected and placed them in sampling jars.
The hot mustard method has advantages over other extraction methods. It is definitely quicker than digging up a large chunk of soil and methodically picking out all of the earthworms, but is also non-toxic and safer than other methods, such as electric shock (which is coincidently how you sample fish populations). Also, if you just want to count how many earthworms there are and then release them, hot mustard is non-lethal. It does make you wonder though about all of the other things scientists poured on the ground before that hot mustard “eureka” moment.
Emilio Bruna, Professor of Tropical Ecology and Latin American Studies at the University of Florida and Institute Director of the University of Florida Brazil Institute, offered further insight from the world of entomology:
In case you need to gather some leaf-cutter ants yourself, all you have to do is coat small pieces of plastic sheeting with your homemade 50:50 water and urine mixture and then place those on foraging trails. Pretty soon you are going to be swimming in leaf-cutter ants. To find out more, check out, “Do herbivores exert top-down effects in Neotropical savannas? Estimates of biomass consumption by leaf-cutter ants” by Alan Costa et al. in the Journal of Vegetation Science.
Bruna also brought to my attention what might be considered by many the bravest of all field research methods. Ingrid Quinetero and Tomas Roslin, in a 2005 paper in Ecology, “Rapid recovery of dung beetle communities following habitat fragmentation in central Amazonia,” include this tantalizing line in their methods section, “Each individual sample was based on a transect of six pitfall traps . . . alternately baited with human dung and decaying beef.” Which make sense, right? Dung beetles like dung and if you need to find some dung really quickly while in the middle of the rain forest, there is one source that would likely come to mind pretty quickly. And if employing your research assistants to donate their own stool to further the cause of science is not a remarkable testament to the will and fortitude of field scientists and their quest for knowledge, I am not sure what is. My hat is off.