Monday, June 23, 2014

Gaining Experience with Think Elephants!

by Ou Yonthantham

Hi, everyone!       

My name is Laddawan, but you can call me Ou. I am one of the new research assistants at Think Elephants International (TEI). I’m originally from Nakhon Si Thammarat, in the south of Thailand. I just graduated with a degree in Conservation Biology from Mahidol University, Kanchanaburi Campus. I first heard about TEI from my co-adviser, Dr. Chomcheun Siripunkaw. She introduced me to Dr. Joshua M. Plotnik, TEI’s founder,  and the topic of elephant intelligence. Later, during my senior project, I chose to study this topic under the supervision of Dr. Plotnik.

Namchoke giving me a kiss!

I chose to study elephants for a few different reasons. First, there are only about 3,000 captive elephants and 3,000 wild elephants in Thailand. The wild Asian elephant population has steadily decreased because of habitat loss, fragmentation, and human – elephant conflict. Therefore, I believe the best way to conserve elephants is through education. Conservation Education (CE) is a process of influencing public attitudes, emotions, knowledge, and behavior about wildlife. At the root of CE lies the idea that if people know about and love elephants, it’s easier to encourage them to conserve elephants

Second, one of the things I find most interesting about elephants is that they are very smart. They don’t have hands like humans but their trunk serves a similar function as the human hand. The trunk is a very important appendage for elephants. Elephants use their trunk to breathe, take baths, grasp food, and interact socially with their friends. We don’t know a lot about how the elephant uses its trunk to make decisions. So, in my independent research study, we investigated how elephants use their trunks to gather tactile information.

Here I’m presenting my project (elephant intelligence) in MUKA Science and Management project exhibition 2014 at Mahidol University, Kanchanaburi Campus.

In nature, elephants touch each other a lot with their trunks. In my study, we showed that elephants can use their trunks to differentiate between things. This is interesting because unlike humans and chimpanzees, which use their hands only to gather tactile information, elephants use their trunks to gather information both by smelling and touching. This suggests we may be able to learn a lot about how elephants navigate their physical and social worlds by studying how they use their trunks. Studying elephant intelligence and behavior also has implications for how elephant conservation protocols are designed.

Elephants use their trunks to gather information.

I like working for TEI for many reasons. First, I like to work with elephants. Elephants are wonderful and they surprised and impressed me while I was working on my project. Additionally, the TEI team is very professional. When I had questions about my project, we discussed it together and felt like a real TEAM! Second, I wanted to practice speaking, reading, and writing the English language. This is a good opportunity for me because TEI’s research assistants are fluent in English and our work is mostly done in English. Finally, I think if you want to get the best experience, you should try something different from other people. Most other conservation biology students from my program are working in jobs not related to their degree. TEI lets me use what I learned about science and animal behavior to directly affect conservation in a way that I really like.

The TEI team poses with Am.

I am very excited to work with elephants and the research team at Think Elephants International. I’m helping to do research and communicating with the mahouts. It’s a very good experience because I get to practice my English skills and learn more about elephant behavior. In the future, I want to study for a master’s degree in Conservation Biology. I will use this knowledge to help conserve wild elephants and let people know about why and how to conserve elephants.


International Zoo Educators Association. (2005). Developing a Conservation Education Program (online).Available:

Srikrachang, M. (2003). Conservation and management of elephant in Thailand [Ph.D. thesis
In Biology]. Bangkok: Faculty of Graduate Studies, Mahidol University.

Wednesday, June 18, 2014

Low Blows: How Elephants Produce Low Frequency Vocalizations

By Sophie Wasserman

Last month, we introduced you to the wide variety of elephant vocalizations (link)--from very low frequency rumbles to higher frequency trumpets and chirps. But at least one question still remains: how do elephants produce this incredible range of sounds?
            To get a better understanding of how elephants vocalize, let’s first examine the basics of sound production in mammals. Remember from high school physics class that sound is a travelling mechanical wave, displacing the molecules of different media like air or water and causing them to vibrate. We can perceive sound because our ears contain membranes that are designed to translate this vibrational energy into signals our brain can recognize-- but that’s a whole different blog post! The important thing to note is that in order to make a sound, you need something for the sound to travel through, like air. Hence, vocalization production starts with the lungs. Elephants have an incredible lung capacity, taking in an average of 8-10 gallons of air per breath, or about 60-80 times greater than that of the average human.

Boonsri is amazed at how much air her lungs hold!

            Of course, what goes in must also come out, and so in the next step of vocalizing, the air is expelled from the lungs by contractions of the surrounding muscles and exhaled through the trachea to the larynx. The larynx, also called the voice box, is mostly made up of cartilage and muscle. It is found in mammals, reptiles, and even amphibians. The key components to vocalizations are two small membranes at the top of larynx called the vocal folds, or vocal cords. In humans, the pressure of the breath builds up and forces the vocal folds to separate until enough pressure has been released that they can recoil and come together again. This cycle keeps repeating naturally and without direct muscle control, causing the vocal cords to vibrate and thus create sound waves. We modulate our voice by loosening or tightening these folds, creating lower or higher sounds, respectively.
Elephant's vocal cords and larynx
Via Shoshani (1998)

Cats, on the other hand, have to actively contract the muscles of their larynx to produce their characteristic purr. Until recently, it was unclear whether an elephant’s rumble was produced in the same way as a human’s hum or a cat’s purr, but a study published in 2012 seems to indicate that they fall in line with humans. To test their theory, the researchers took the larynx of a zoo elephant who had died of natural causes and hooked it up to an aluminum tube. When they passed air through the vocal cords, the larynx produced sounds similar to that of a typical elephant rumble, demonstrating that the active muscle control of purring is not necessary for elephants to produce sound.

Cats use active muscle control of their larynx to purr
via Wikimedia Commons

The final step in the process of producing vocalizations is fine-tuning and modulating sound with the mouth. For humans, the positioning of our tongue and teeth can differentiate between consonants and vowels. In the elephant’s case, the way in which it holds its head, mouth, tongue, and trunk can modify the type and frequency of sound that it produces. For example, an Asian elephant will open her mouth when rumbling but will close off the tip of her trunk when chirping and squeaking. Most trumpets are produced with trunk raised, though this could be a behavioral cue instead of, or as well as, a way to modify the vocalization produced.

Elephants modulate sounds with trunk and mouth positioning

Still the question remains, how can elephants go so low? In other words, how do their rumbles contain infrasonic components as low as 10-12 Hz, or sound waves at a frequency below the human hearing range and about 3 octaves below the typical frequency of a human male’s voice? The first reason is that they’re huge animals. For instance, compare a violin to a cello: the longer the string and the larger the resonating chamber, the lower pitched the sound. Elephants, by nature of their size, have naturally longer vocal cords of about 7.5-10 cm in length compared to the measly 12-24 mm of humans. They also have a built-in resonance chamber in their two-meter long trunk, increasing the volume of air the sound passes through and lowering the pitch of the sound produced. Finally, the elephant’s hyoid bone, which provides support for the tongue and larynx, is comprised of five bones rather than the typical nine, and it is not attached to the skull directly, but atypically connected by ligaments and tendons. This enables greater flexibility of the larynx, which in turn allows their vocal cords to stretch even beyond what you would expect and produce even lower sounds.

Elephant vs human larynx
via Herbst (2013)

All of these adaptations, which enable the ultra-low frequency rumbles, allow for the communication of elephants across vast expanses, a necessity born of the structure of elephant society. Female elephants, who live within a familial herd, often use rumbles to gather together disparate herd members while male elephants will emit distinct rumbles during musth (their peak of sexual activity) to communicate with potential mates from far away, since they tend to live on their own or with loosely bonded male compatriots. In this way, the physiology of elephant vocalizations reflects the challenges and limits of their physical and social environments. But the production of the sound is only half the story; next month we’ll look at how the elephants on the other end of the communication perceive and localize the calls of their kin. 


Herbst, C. T., Stoeger, A. S., Frey, R., Lohscheller, J., Titze, I. R., Gumpenberger, M., & Fitch, W. T. (2012). How low can you go? Physical production mechanism of elephant infrasonic vocalizations. Science,337(6094), 595-599.

Shoshani, J. 1998. Understanding proboscidean evolution: a formidable task. Trends in Ecology & Evolution 13, 480-487.
Cat by Sameer.S via Wikimedia Commons
Herbst, C. T., ┼ávec, J. G., Lohscheller, J., Frey, R., Gumpenberger, M., Stoeger, A. S., & Fitch, W. T. (2013). Complex vibratory patterns in an elephant larynx. The Journal of experimental biology216(21), 4054-4064.

Monday, June 9, 2014

How To Guide: Performing an Elephant Health Check

by Lisa Barrett

After your first snack of grass and sugarcane, you felt a little bit queasy.  A few hours later, after another quick bite of bananas, you started feeling downright lousy.  You've made it to the doctor's office to get a checkup, but discovered a slight problem: your doctor doesn't speak elephant!  What can you do?

Like Somjai here, the elephants we work with receive regular health check-ups.
Photo by: Lisa Barrett

Since elephants cannot tell us when they are feeling ill, we rely on regular health checks to measure whether an elephant is healthy or sick, overweight or malnourished. Elephant veterinarians usually perform these checks on a monthly basis at the Golden Triangle Asian Elephant Foundation’s target training wall while employing positive reinforcement techniques (read more about target-training here). In addition, mahouts, elephant caretakers, will report any abnormalities or illnesses in his elephant to the vet. So, what are the steps of a basic elephant vet check?

What’s Up, Doc?
Before approaching an elephant, the vet will want to assess the body state of the patient and be sure that the elephant’s mahout is present. An upset elephant will likely have her ears pushed forward and her tail sticking straight out or up. These postural cues indicate that an elephant is not safe to approach. A good way to greet your patient is by handing them a nice handful of sunflower seeds, a delicious treat for elephants!

If Am's tail was erect and ears were pushed forward, it may not be safe to approach her.
Photo by: Lisa Barrett

“Eyes and Ears and Mouth and Nose…”
Next, the vet will check to make sure that the elephant’s eyes are bright and clear and that they are not secreting a lot of excess liquid. Dull eyes would indicate sickness or pain. It is normal for elephants to appear as though they are crying, because these tears help them flush out debris from the eyes (and these tears likely are not the same as when humans weep and emotionally feel sad). Liquid pouring from the eyes, however, could signify an ulcer or eye infection needing treatment. Similarly, an inspection of the ears for any smelly secretions is critical to a health check up. A cooperative elephant will also allow the vet to look inside of their mouth to check for any mouth sores or growths, and to count out four healthy teeth. If an elephant’s mahout has reported breathing problems in their elephant, the vet may also investigate the trunk to make sure airways are clear of any sticks or other obstructions.

We can tell a lot about Lakheng's health by checking her eyes.
Photo by: Lisa Barrett

Breathe In, Breathe Out
Checking the respiration rate of an elephant can be a hefty feat, as the giants do not like to stand still. At any rate, we can look at the elephant’s abdominal area to attempt a breath count. Believe it or not, they only breathe four to twelve times per minute!

How do we measure the pulse of an elephant? We place one or two fingers on the largest artery behind the ear. Interestingly, an elephant’s heart rate may triple in an attempt to get blood to all of their extremities if it is lying down. And just like your heart rate might be faster when you are at the doctor’s office, so might an elephant’s when she is with the vet!

We can measure an elephant's pulse on the back of her ear.
Photo by: Lisa Barrett

Skin & Toes
To be sure there are no rashes or fungal growth on the body of an elephant, a vet should examine the skin carefully. Believe it or not, some bug bites can pierce elephant skin, and the thick skin can close over the top and create an unhealthy ulcer if not cleaned properly. The skin should feel soft, hairy, and wrinkly.
Perhaps the most important part of the elephant body, feet and toenails require regular inspection for cracks, punctures, and pain. The mahout and veterinarian will also pay careful attention to whether the elephant is favoring a leg by observing her gait.

Asian elephants have five toenails on their front feet.
Photo by: Lisa Barrett

Step on the Scale
Most elephant vet checks will include weighing the animal, but if a facility does not have an elephant-sized scale, one can use a formula as a weight estimate. For adult elephants, this formula involves measuring the chest girth of the elephant, multiplying by 18, and subtracting 3,336.  A healthy female elephant weighs around two to three tons!

Vets will also keep a record of the elephant’s shoulder height, another measurement which we can estimate. By multiplying the circumference of an elephant foot by two, we get a fairly accurate guess at the elephant’s shoulder height! In other words, if you found an elephant footprint in the wild, you could measure its circumference to determine the body size of the wild elephant in that area.

Lastly, a vet can use body condition scores to evaluate whether an elephant is underweight, overweight, or just right. By using a standard yet subjective scoring system, he or she will rate different body areas (temporal, scapular, pelvic, etc.) between zero (for very little fat) to one (for very filled out). Summing these scores provides a total score that falls between zero and five—between malnourished and overweight.

A malnourished elephant (top) compared to a very full elephant (bottom).
Photo from: Fernando et al. 2009

Final Touches
All of these steps equip an elephant veterinarian with enough information to assess the general health of an elephant. It is important to have these regular check-ups so we have a record of each elephant’s health history. From being careful about approaching her patient to carefully assessing the health of each body part and the body as a whole, being an elephant veterinarian is “no small feat!”

Monday, June 2, 2014

Citizen Science: A Collaboration of Minds

By: Elise Gilchrist

I listened to a podcast this week called ‘Why We Collaborate,’ as part of the weekly NPR "TED Radio Hour" program.  Each week, NPR plays excerpts from TED talks about related topics and interviews the speakers.  The host, Guy Raz,  spoke about collaboration, and the different ways that people use modern technology to enhance and fuel group efforts. One of the most impressive examples of this type of collaboration is Wikipedia. Wikipedia is a free, online encyclopedia that is co-authored by thousands of people all over the world. Wikipedia now has 30 million articles written in 287 languages, so it is clearly an impressive collective effort. The podcast discussed other examples of instances where the public comes together to contribute to a common goal, such as a system where members of the community can ‘adopt a hydrant’ and they are then responsible for shoveling it out in snow storms. This theme of modern day, large scale collaboration struck a chord with me, and made me think of a concept I have recently become more familiar with, the idea of citizen science.
Citizen science is scientific research that is conducted, either in whole or in part, by amateur or non-professional scientists. In other words, citizen science is public participation in scientific research.  Just like Wikipedia requires input from thousands of non-professionals, scientific studies often benefit from contributions by non-scientists. My first personal experience with citizen science occurred when I was in college and conducted a research project about urban red-tailed hawks. It was important for my dataset to show where the hawks spent their time on campus and what time of day they were most often seen in the field. I did a lot of bird watching, trucking across campus with binoculars and clipboard in tow, but I could not be ‘in the field’ all the time. One of my advisors set up an online system where  any student that saw one of the hawks could complete an online form.  When they hit send, I would immediately receive the report in my inbox. Admittedly, many college students found the process dorky and ignored it, but a number of students and faculty used the system regularly and helped me target the raptors. I was able to finish my report with a data set fueled by the power of citizen science.

A red-tailed hawk from the population I studied.

Citizen science is a concept that has shown success for  numerous large-scale research projects in varying fields. The Cornell University Lab of Ornithology was one of the pioneers of this concept and has been using data collected by birdwatchers for decades. More than 200,000 people contribute to their projects each year, helping to collect data about migrations patterns, effects of acid rain on different species, population density, and many others. Other research groups have picked up on this trend and called to action citizen scientists from all over the world. REEF, a grass-roots marine conservation organization, recruits both scuba divers and snorkelers to complete fish surveys that are entered into a collective database, which has led to key information for fisheries management and even the discovery of new species. The Great Sunflower Project has been gathering information from the public about pollinators in North America since 2008. Think Elephants International utilizes citizen scientists as well: in our work with the Earthwatch Institute.
Earthwatch is an environmental charity that brings together volunteers and scientists from all over the world. There are a huge number of research projects and teams that volunteers can join, from observing cheetahs in Africa to counting macaws in the Amazon.  Think Elephants is going into our third season working with the Earthwatch Institute and their enthusiastic volunteers, in our "Thinking Like an Elephant" field program. Our research team works year round to develop and implement elephant cognition projects, but it is not until our volunteers arrive in May that we have the man power to conduct research with the rigor and pace we strive for.  Most importantly, our volunteers provide the extra eyes necessary to conduct behavioral observations of our captive populations, allowing us to collect a huge dataset of interactive behaviors.  Our volunteers come from many different backgrounds, from teachers to lawyers, but they share a common goal: to help the research team learn more about the mind and intelligence of the Asian elephant. With their help at the stopwatch calling out time delays, or with the clipboard collecting behavioral observations, or in the office entering data, we are able to accomplish a significant amount over the course of their stay.

Earthwatch volunteer from our first team of the season.

With Asian elephant populations on the decline, time is running out to discover just how intelligent and complex these animals are.  We need all the help we can get to gather data, and Earthwatch does just that by providing us with passionate helping hands.  With the help of citizen scientists, the Think Elephants team continues to find out more about the elephant’s intellectual capabilities. 

Raz, G. (2014, May 16). Why We Collaborate. NPR TED Radio Hour

"Citizen Science." Wikipedia, The Free Encyclopedia. 26 May 2014

Cornell Lab of Ornithology:


The Great Sunflower Project:

The Earthwatch Institute: