This week’s BEACON Researchers at Work blog post is by MSU postdoc Eben Gering.
I. The Land of the Leech
This spring I received a last-minute invitation to join a French film crew in Thailand, which left me a) totally stoked! b) with virtually no prep time. And so I found myself arriving in Khao Yai National Park with a mess of hastily borrowed equipment, abundant enthusiasm, and very little basic information about the region.
For example: did you know that Southeast Asian forests are home to a 150 million-year-old, ten-eyed beast whose name means blood thirsting guts? If you don’t perhaps you are picturing something along the lines of the fantastical Naga (Figure 1) – a ferocious serpent believed to protect the Buddha. Naga guard temple entrances throughout Thailand, but are nowhere near as ubiquitous as Haemodipsidae (Figure 2) which, FYI, are hermaphroditic land leeches.
When our guide first offered us prophylactic “leech sox” I didn’t want them. In my undergraduate days I had read a terrific book1 about tropical biology which eventually helped land me in this Thai jungle many years later. One of the book’s most memorable chapters (recapped in a recent radiolab episode) concerns an evolutionary biologist who lets a parasitic botfly pupate in his head for heuristic (learning) purposes. Botfly husbandry has since become a fashionable act among a small and hardcore subset of tropical biologists.
The idea of joining Club Botfly makes me a little queasy, and involves an apparently painful initiation too. But leeches – painless, virtually incapable of transmitting disease, a boon to human health and medicine for at least three millennia – provided an attractive alternative source of field “cred.” In fact, I’ve been quite curious about these animals since meeting Mark Siddall, a passionate and persuasive expert on leech biology who “fishes” for his study subjects by dangling his legs in murky water. In parallel manner, Dr. Siddall advocates for these greatly maligned creatures. He lures his listeners past the ‘ick’ reflex into a reluctant appreciation for their elegance and mystery. It is, after all, an animal which once fed on dinosaurs, and outlived them, and will probably outlast us.
An enlightened view of the leech is also apparent in Khao Yai’s local, Buddhist residents, who point out their relative harmlessness with the saying:
The hero of Khao Yai National Park…
They eat blood but not the trees! 2
Will I be able to get a leech if I don’t wear the sox? I asked Tony, our guide. But I needn’t have worried. In the coming days I would have many chances to observe sanguivory (bloodfeeding) first hand. Leeches would be so abundant at times that we would see and hear them moving towards us on the forest floor.
II. Why won’t the chickens cross the road?
The chief purpose of our expedition was to visit the Red Junglefowl (Gallus gallus) within its native range. These extremely wild and elusive birds (figure 3) are the domestic chickens’ closest relatives. The French guys (Figure 4) were out to gather the world’s first 4k footage of wild Red Junglefowl. I, in turn, hoped to gather audio recordings and compare vocalizations to those from a non-native (Hawaiian) G. gallus population. Our recent research3 indicated that Pacific island G. gallus share both Red Junglefowl and “chicken” (i.e. domestic) ancestry. We are now investigating which wild, domestic, and/or hybrid traits have been favored in these feralized populations.
During our first days out, we occasionally heard Red Junglefowls calling from deep within the forest. That’s a somewhat surreal experience for western eyes and ears, because they look and sound just like backyard roosters, yet glide through primary tropical forests without effort, thriving among leopard cats and pythons.
From day one, I was able to collect audio recordings, but our efforts to film (with a menagerie of cumbersome gear) typically sent our targets fleeing dozens, or even hundreds of meters into impenetrable growth. A day’s work yielded only a few precious minutes of 4k video.
On day two, the production director (Benoit) put his cameraman (Nicolas Cailleret, a professional falconer back in France) in a camouflaged bird blind. We left him there before sunrise in an area where we’d seen junglefowl eating figs. Later a hornbill polished off the figs, so we decided to bait the area with another of the Red Junglefowl’s preferred food sources: elephant dung (figure 5).
As I grabbed my first handfuls of the dung, which was surprising lofty, fibrous, and not the least bit stinky, I thought how much I love my job. I was 11 time zones from home, and almost intoxicated by the nearly deafening whirs of the cicadas, the sweet and mournful ‘bwoooooops’ of gibbons, the bright flapping of birdwing butterflies gliding on hot, humid air.
While we picked the freshest dung we could find, the waste of our planet’s largest herbivore was already becoming a complex ecosystem. By coincidence, the book I mentioned earlier 1 (and highly recommend) a
lso contained a whole chapter on poop – specifically, how scatophagic4 organisms colonize and compete for this rich resource within minutes of its “birth.”
III. In praise of Bill Nye
While our brief experiment with elephant dung brought on an existential rapture, it did not bring any Junglefowl in front of the camera. Soon, however, Benoit and Nicolas found other ways to catch clips of the birds in stealth (figure 6). They crouched underneath a camouflage tarp in the bed of Tony’s rolling truck, ready to start shooting when Junglefowl were spotted. They learned and patrolled a few territories’ boundaries. And then, when they had acquired sufficient footage of their non-human prey, they turned the camera on me.
I am curious to see myself on French television, but not worried a bit. I cannot possibly look worse than I felt. For two days I had been crowing for the camera, a one-eyed monster that emitted so much heat it required its own water breaks. Usually this work was done standing in direct sunlight, sometimes while peeling off leeches… whose novelty was waning (sorry, Mark!). The heat seemed to fog up my brain, making it a struggle to follow simple instructions or speak intelligibly. And I could see that this was beginning to try the (extraordinary) patience of the crew – two men who had just spent uncomplaining days in a sauna-like blind surrounded by elephant poop.
On our last afternoon, we all spent an hour crouched in that small, poorly vented vinyl blind collecting footage of me photographing imaginary junglefowl. Nicolas held the camera a few inches from my face while Benoit held the microphone over my head. We were as close together as the heads of the Naga (Figure 1), and it was so hot in there – so very hot and humid (and the whole shot seemed so unimportant) that I wondered if perhaps they were trying to kill me in order to increase their film’s marketability.
But apart from such moments of heat and performance-induced panic, it was a joy to watch Benoit and Nicolas work. There was boldness and creativity in every step of their process, from handling equipment failure, to avoiding extortion by corrupt officials, to framing a narrative arc across this wild landscape, its diverse wildlife, and their bumbling biologist that would eventually reach into the homes of French families.
I was eager to participate in Benoit and Nicolas’ film because nature documentaries helped cultivate my interest in biology. And as a scientist on the more right-brained end of the spectrum, I enjoy seeing artists at work. While I would jump at another such chance, our filming of just one segment (25%) of a 45 minute show was both physically and mentally exhausting. I couldn’t do this work everyday, and have redoubled my respect for the stamina of David Attenboroughs and Bill Nyes.
When I first read Tropical Nature1, my game plan was to become a writer for a documentary production company. But I have since become increasingly fascinated with basic research questions, which take sustained (and sometimes boring) effort to answer. Benoit, on the other hand, began his career as an acarologist (mite expert) before transitioning out of research and into film. The mite work, he said, was much too specialized to match his interests. I could understand this, I said, but also asked him to tell me more about the mites. I think we have chosen wisely.
1 Forsyth, A., & Miyata, K. (2011). Tropical Nature: Life and Death in the Rain Forests of Central and South America. Simon and Schuster.
2 Translation by Elizabeth Borda
3 Gering, E., Johnsson, M., Willis, P., Getty, T., & Wright, D. (2015). Mixed ancestry and admixture in Kauai’s feral chickens: invasion of domestic genes into ancient Red Junglefowl reservoirs. Molecular ecology.