The Cricket WomanBy vijaysree venkatraman | September 16th, 2013 | Category: Scientific American Blog |
Physical courage is generally not a requirement for studying science, but field biology seems to call for this quality. Swati Diwakar, 34, spent many a night in an evergreen forest in South India collecting data for her dissertation on crickets taking the occasional viper bite in her stride. As assistant professor in the department of environmental studies at Delhi University in India’s capital, she is now looking to recruit research students. I chat with my compatriot, mother of a toddler, about her work.
Cricket, the sport, has millions of aficionados in India. How did this insect become your research subject?
I have not even heard a cricket call, not consciously at least, before I went to went to the Indian Institute of Science (IISc) for graduate studies. The campus is so sylvan there are coffee table books about its rich flora and fauna. To pick my dissertation topic, I went with my doctoral supervisor to sites on campus, two national parks, and wildlife sanctuaries in the Western Ghats, a mountain range known for its biodiversity. That is where I heard crickets first and I was hooked.
Before this I was doing a masters degree where I was stuck in the lab all the time — I knew I did not want to there for the rest of my life.
Broadly ‘cricket’ refers to field crickets, tree crickets, bush crickets (katydids) and king crickets (wetas). When I set out on those field trips, we only knew the taxonomic identities of these insects from the Western Ghats complete with type specimens – first examples of their kind – locked up in museums. We knew little about their bioacoustics, the sounds they make.
Why do crickets create such a racket anyway?
Male crickets call to attract females, who then respond. They are most vocal at dusk and some carry on well into the night. Each species has its own unique frequency and characteristic patterns. We wanted to document and inventory these calls for all existing species in the region. Then we’d have a quick and non-invasive way to check the health of that forest. If habitats get turned into plantations — or regions of lesser diversity — one expects to see a change in the kinds of species, and a change in the numbers of individual species inhabiting the area as well.
In tropical forests, animals that communicate through sounds have to compete for broadcast channels and time. There is a whole chorus in the wild. How do crickets operate in this noisy environment? There was so much to find out.
Did you discover any new species as you went about recording the sounds of crickets?
For insects, most parts of the tropics are still very incompletely surveyed – the work was done during British India and there was no sound sampling back then. Our acoustic recordings allowed us to discover some species which, we believe, are new. For crickets and frogs, a different sound pattern should allow you to assume that what you have is a different species. Because most type specimens from earlier times are in the collections of the Natural History Museums in Europe (mostly Paris and London), comparison with the original is problematic. Formally naming any new species is going to take a while. In any case, that is the work of taxonomists.
What was it like to venture into the jungle for fieldwork?
Kudremukh National Park, where IISc has a field station, was my study site.
I am city-bred and had not camped outside before. I had climbed nothing higher than a guava tree. But If I need the data, I have to get it, right? I was determined to do that. Crickets are everywhere from the floor to the canopy of the forest, so I carried a portable ladder. Besides, the field assistant was an excellent tree climber. There were others with me: a project assistant, and a forest guard armed with a wooden stick fashioned from the branches of a nearby tree! Our jeep driver would also come out of curiosity to see what I was doing.
I did not know the local language they spoke. So I picked up the Learn Kannada in 30 days book. Sometimes, I called the campus from a telephone and asked few mates to talk to them or simply used dumb charades principles. And yes there is poor or intermittent cell phone connectivity so you feel isolated from the rest of the world during fieldwork. But I was never uncomfortable being in the minority gender-wise. I was only afraid of wildlife encounters…vipers next to my shoe, an elephant thirty meters away, or a boar charging!
From 2002 to 2006, I set out after the monsoons – September till the end of March was good for fieldwork. But I would come back to campus after every three weeks or so: take stock of data, spend a week or ten days in lab updating data, replenish supplies of antihistamines because I’d developed allergies to tick and leech bites.
Do you find it difficult to get researchers now as a Principal Investigator yourself?
Some students run right out of the door when they learn that there is no bench work involved in the lab; others run after knowing that their workbench is actually the forest, and that too at night. A couple of students had shown interest and motivation but I lost them to outsourcing or biotech companies which pays them a salary higher than a PhD scholarship. I have one doctoral student currently and his field site is limited mostly to university campuses in Delhi. But we plan to go to the Western Ghats, and the Himalayas, another biodiversity hotspot, to study king crickets which have thus far been reported only in New Zealand.
Is this research that takes you outdoors and at odd hours a tough sell to women given that sexual assaults on female students and professionals have been making headline news lately?
I was never verbally or physically harassed or assaulted in Bangalore, where IISc is located, or in any of the places in South India where I did fieldwork for my thesis. I am, however, quite concerned about how a girl student will carry out work in and around Delhi. I would never send anyone alone into the forest – they’d go as a team, just as I did. Plus, PhD students can devise their work plan to assist one another in data collection.
Is there any way to monitor crickets without going to the forest ? Or does your research demand boots on the ground?
Automated bio-acoustic monitoring is the latest method for assessing species richness. These techniques are mainly being tested out in temperate forests with comparatively low diversity. Even where it has been used in tropical forests, there are technical limitations. The frequency band between 3-6 kHz (where most of the field crickets call) is still difficult to resolve with automated recording techniques. And we can’t count the number of insects from afar.
So, yes our group still has to go to the forest to study crickets.
Read the unedited article here. html.