As I mentioned in my introduction, I am working on my own project in addition to the research we are doing as a group. During our time in Monteverde, I’ll be setting out traps to see if parasitoid wasps in Costa Rica are attracted to a chemical called cantharidin. Cantharidin is a toxic chemical produced by blister beetles and false blister beetles as a defense (Hashimoto & Hayashi). Previous similar experiments captured a few of these wasps, but not nearly enough to definitively establish that some are attracted to cantharidin. At the suggestion of Paul Hanson, a professor studying hymenopterans (ants, bees, and wasps), I started planning an experiment to discover if any could be found.
Earlier in the summer, I set several traps in prairie areas of the KU Field Station, but a cloud forest in Costa Rica is considerably different from the grasslands the traps were originally designed for. A few elements had to be changed from the original trap to be better suited for the new environment. The initial traps were inverted funnel traps made of 2 liter soda bottles with cantharidin-impregnated filter paper as bait. An inverted funnel trap works on the idea that many insects will be able to climb into a hole, but will fly straight up when trying to escape. Having a small hole allows insects to enter, but prevents them from leaving. The bottle was made into a trap by cutting off the top where it starts to curve, then putting it upside down. In both locations, I put alcohol in the bottom of the trap to kill whatever insects landed in the bottom and then preserve them until they could be collected. Traps were attached to a wooden stake with waterproof duct tape to ensure they would stay upright.
The big difference between the traps was how I dealt with the issue of keeping the bait dry. I was told that filter paper holding the bait could not get wet. In Kansas, I focused on minimizing the problems caused by water getting the traps. To keep the bait dry, I suspended it from a wooden dowel put through holes in the side of the trap. With the bait in a safe place, I only had to prevent the trap from flooding. To do this, I made a few holes slightly above where the alcohol was and covered it with mesh to allow any excess liquid, likely rainwater, to drain out. In Costa Rica, I had the opportunity to prevent rain from entering the trap at all. To accomplish this, I made several rain covers using garbage bags, duct tape, and twine. This allowed me to suspend the bait with a strip from a ziplock bag and some tape. The advantage of this method is that I can put the bait directly under the hole in the trap, which makes it more attractive to insects. These traps can be seen in Figure 1.
One thing to note is that with the exception of the bait, all the materials used in the traps can be purchased at a grocery store for a few dollars. Science experiments don’t have to cost a fortune to carry out. A few household products and a little bit of preparation can answer plenty of questions.
Hashimoto, K. and Hayashi, F. (2014) Cantharidin world in nature: a concealed arthropod assemblage with interactions via the terpenoid cantharidin. Entomological Science 17: 388-395.
Image: Insect trap set-up used at all three sites in Costa Rica (Photo credit: Eric Becker)
Note: this post is one of dozens written by students participating in a 2015 field course in Costa Rica. The entire series is here.
Botanist Willow Zuchowski joined us on one hike through the Monteverde Biological Reserve. I learned more about identifying plant families from her in five minutes than I did in the first week and a half. Willow is from the United States and moved here after her bachelors degree to work on a hummingbird project; she loved Monteverde and Costa Rica so much that that turned from a year and a half to three years to living here for the past 30 years. She actually does not have a masters degree or a PhD. What she does have is the motivation and interest to learn about her field in a non-traditional setting. She has been a field assistant on many projects here and her colleagues here respect her knowledge without a formal graduate degree. She has travelled back to the states a few times to take courses in biological illustration and desktop publishing because she is interested in those things. She has now illustrated and co-authored a book called An Introduction to Cloud Forest Trees: Monteverde, Costa Rica.
The moral of this story is that if you love something enough and are motivated enough, you can make it happen. I intend to "carpe diem" by going on many more study abroad trips to see the world, and I may even find a place that I want to settle down like Willow did. Carpe diem everyone. Seize the day.
Left to right: Willow Zuchowski, Dr. Chaboo, Willow’s husband Bill, and Kenji Nishida
The second week of our trip is being spent at the Monteverde Biological Reserve. We had another seminar, this time by Dr. Joseph Alan Pounds, about the impact of climate change on cloud forests.
During the talk, I was looking around the classroom and noticed two mammal skeletons, an ocelot and a quati. As I looked at them more closely, I noticed that their rib cages were not closed like ours. It seemed baffling at first, but the more I thought about it, the more it made sense. When walking on four legs, your chest is not exposed, but while walking on two legs, your chest is very exposed. When your chest is more exposed, you are more likely to get impaled there. My hypothesis is that throughout our history as we began to stand more upright, those hominids with a mutation for a more encompassing rib cage were more likely to survive being impaled with a spear, stick, talon, or horn than those with more open rib cages. Your rib cage protects your heart and lungs from getting stabbed as something is more likely to hit the ribs than go between them. On this trend, some day we may have a fused rib cage.
Imagine walking down the street. You notice several people giving you sideways glances or double-taking as you go by. You see older people glaring, and others seem to think you look like a side show attraction. You have tattoos and piercings that are quite visible and people don't seem to know how to act when they see you.
Now imagine this: you are walking down the street. Everyone is in a hurry to get where they need to be or are talking joyously with their group of friends. You can walk for a great distance and no one really gives you a second thought. The group that you are in stands out as a bunch of gringos, but no one is overtly rude by staring.
The first scenario is a typical day for me in the United States. The second is my experience in San Jose, Costa Rica. While back home people seem to judge me for my body modifications, here they don't seem to really care, which is surprising to me because I was expecting it to be worse here, in a very Catholic country.
Several people have tattoos in Costa Rica, but facial piercings are a tad more scarce. Either way, the crowds of people you pass in the street seem more interested in going somewhere than to be bothered by someone who looks different. It is a pleasant change from how Americans act.
In our daily walks along trails at the Zurqui de Moravia site near San Jose and here in the Monteverde Cloud Forest, we take advantage of fallen trees and broken tree limbs to test out our botany knowledge, add a few more families to our life lists, and poke around for hidden snakes, frogs, and especially insects. I don’t have the heart to peel off the carpet of mosses, filmy ferns, and flowering orchids to find beetles and bugs. Documenting the arthropod community living in the phytotelmata of a bromeliad is destructive sampling – tearing leaves apart and using forceps to spread the soil. Fortunately, this is not the focus of my current research nor permitted by my Costa Rica research permit; thus, I am spared the conflict of attacking these gorgeous bromeliads for cryptic insect treasures.
Going on a study abroad program for field research can be a great opportunity for Biology majors, especially those that are Organismal biology or Ecology and Evolutionary Biology. On trips like this you can get field experience, conduct some of your own research, and get funding for your research and the trip through awards. Normally you would start a personal research project based on your personal interest (herpetology, ornithology, etc.), but sometimes on trips like these because of it being a first time and because of permits, it may be easier to find a research project in the field that the professor leading the course is focusing on. For example, although I am primarily interested in herpetology (study of reptiles and amphibians) because I am not too familiar with permits yet I have been conducting research on insects -- the professor I have gone on the study abroad trips with is an entomologist (studies insects).
So to begin, I would suggest meeting with your professor that is leading the trip and ask if they have any projects that you can do personally in mind, or to try and come up with your own research idea based on the research the professor concentrates on. From there you can come up with a research proposal to collect your ideas/info on what you want to research and how you are going to perform that research, and to present for obtaining research awards. At KU, good places to look for ways to fund your research are the Center for Undergraduate Research’s Undergraduate Research Award (UGRA), which is offered for the spring, summer, and fall semesters, and at the various awards that are posted on the undergraduate biology website. The ways to apply for these awards will be listed and are easy to follow. After applying and while waiting on the awards you have time to plan out the specifics of your research pertaining to the trip such as what traps you need to get, how you will collect the specimens, etc.
After the awards come through, which hopefully they will, you can then go out and get these things you will need for your research and the trip. During the trip you perform the basics of your research and collections, then after this is done you will change your research proposal to a manuscript and fill in the data for the research and extra information as you go along processing your collections and information. When finished with the manuscript you can then try to get it published and give presentations on your data either at KU or other places as well.
A common expectation in education involves accepting the information delivered in lectures and conveyed in textbooks. Students must accept that complicated chemical reactions proceed as described in the literature or that their ecology professor accurately describes how a rainforest functions. After all, authors and professors providing these educational materials devote their lives to investigating these subjects; why would anyone doubt their credulity? However, this often means that students are deprived of direct contact, only learning things indirectly via photographs or perhaps video footage as visual aids. I was exhilarated to witness one such phenomenon while touring the University of Costa Rica where the campus is filled with the extensively researched and tropically endemic leaf-cutting ants. Prior to this field expedition, I had only read of these extraordinarily complicated specimens and learned of them in KU biology courses like Principles of Organismal Biology (BIOL 152) and Evolutionary Biology (BIOL 412).
Leaf-cutter ants are tropical creatures that chew off the foliage of plants and transport the leaves back to their nest where they use the leaves to cultivate a fungus garden. In the picture above, you can see a group of leaf-cutter ants transporting nutritional leaves into their nest to cultivate their fungus garden. These colonies can consist of up to four million individuals. This fungus garden is what the ant colony uses to feed their maturing larvae.
This animal-fungus relationship is a typical example of a phenomenon called mutualism in which two species directly interact with each other in ways that substantially benefits both parties. However, this system is even more interestingly intricate. A separate, microscopic fungus, which I will refer to as a mold for the sake of distinction, parasitizes the fungus garden that the ants depend on for food. In response to this pest, these gardener ants have developed a pesticide to treat their garden to kill the mold. Within the crevices of the ant’s exoskeleton, colonies of antibiotic-producing bacteria reside and synthesize chemicals that prevent the garden from being destroyed by the parasitic mold. This interaction is suspected to have coevolved along with ants during their evolutionary history (Currie et al. 2006).
When this quadripartite system of symbiotic relationships was discovered, it excited biologists due to its embodiment of several different biological phenomena—mutualism, parasitism, and coevolution. Indeed, this system remains a developing corner of research and proves to be even more complicated than originally thought. It is exciting to observe a famous textbook model during my travel in Costa Rica.
Reference: Cameron R. Currie, Michael Poulsen, John Mendenhall, Jacobus J. Boomsma, and Johan Billen. “Coevolved Crypts and Exocrine Glands Support Mutualistic Bacteria in Fungus-Growing Ants.” Science 6 January 2006: 311 (5757), 81-83. [DOI:10.1126/science.1119744]
When most people think of herding, an image of a cowboy walking a herd of cattle across an open plain often comes to mind. The insect world, however, has a far more intriguing example of herding.
Despite having been in Costa Rica for only a few days, several groups of herding ants have been discovered in the various sites that the group visited. Looking from an outsider’s perspective, there seemed to be nothing more than a small size group of animals nestled together under the branch of a tree. Upon closer inspection however, one can truly appreciate the naturalistic relationship between the herding ants and their “cattle.” While out on the University of Costa Rica campus, the first group of herding ants was uncovered (see photo at left, by Kyle Clark). The animals being herded were the larval( or nymph) form of Florida, burrowers that dig into the branches to suck the nectar out of the tree. Because the branch contains high amounts of water, the bugs that are absorbing nutrients from the branch release a large volume of sugar filled urine. As these larvae suck out and secrete the excess sap for the ants to consume, the ants patrol the branch, protecting their herd from danger. The larvae continue to eat, the low nutrition-to-liquid ratio quickly leads to an excess of sugary liquid that develop around the animal’s rear. The patrolling ants can then “milk” their cattle, consuming the nectar off the larvae’s body.
The following day, the exact same interaction between more herding ants and aphids were observed on the stem of another small plant (see photo by John Kaiser, below). This "ant herding" interaction between the two species is a text book example of mutualism because both the organisms benefit greatly from the others exisistence and production. Relationships like these are truly fascinating to us because it shows how two organisms can co-evolve to survive and be successful! - Kyle Clark and John Kaiser
Costa Rica has approximately 110 out of 1,100 species of bats. Out of all the species of mammals in Costa Rica, bats make up approximately 50% of the mammals found in the country.
There are several different types of bats, classified by their diets. Found only in Central and South American countries, there is Desmodus rotundus, or the common vampire bat, which is a sanguivore, meaning they consume blood. There are also nectarvores, which eat the nectar of nocturnal flowers and are major pollinators. Fruitivores are fruit eating bats, and finally, carnivore bats, which eat frogs, insects, fish, and even other bats. Costa Rica is home to all of these kind of bats.
In 2006 renowned bat biologist Richard LaVal opened the Bat Jungle, a world-class bat exhibit. The attraction includes a microphone that can pick up on ultrasonic sound waves, allowing their guests to hear when the bats echolocate, a bat cave with 100 bats. They have feedings scheduled throughout the day and have a small bat that cannot fly that guests can see up close and personal.
Scattered around the reception area are several posters with lots of bat information, ranging from common misconceptions to skeletal structures of popular bat species.
After one long week of no bat sightings, we finally to got to see some bats. Our tour guide impressed me greatly. He was very well informed on current bat information. During the tour he told the group about the white fungus issue happening in North America and about the nearest information on how scientists are finally able to treat bats with it. This information was released about two weeks ago, so it was very current and a good thing to share when touring with a group of biologists. Our guide took us into the bat cave, which was amazing, and held a flashlight on the bats for us to get pictures of them. He even feed them so our group could see them dive in for some watermelon chunks.
After we left the bat cave he brought out Oscar, the little bat who couldn't fly, and allowed our group to pet him to feel his tiny body shake from his rapid heartbeat. As an aspiring bat biologist, this tour was the highlight of the trip so far.
Photos by Vickie Grotbeck and Kayla Yi
While staying at the Monteverde Cloud Forest Reserve, we met with many experts from the surrounding community. Dr. Pounds was one such expert. He studied the Golden Toads and their mysterious decline. Our group had the chance to listen to a lecture given by Dr. Pounds after a day of field work. He spoke of his work with Golden Toads and the possible causes of their decline. He also lectured about the changing meteorological landscape of the cloud forest.
I found this portion of his discussion quiet interesting. These days it is difficult to speak to someone about climate change without things becoming political. It was refreshing to hear a lecture that presented facts, and didn’t attempt to promote a particular agenda.
Dr. Pounds began his lecture by discussing a variety of animal species from the forest that have died off. These die offs occurred during particularly dry periods. These die offs promoted Dr. Pounds to research the changing climate of Monteverde. He investigated the frequency, duration, and intensity of wet and dry periods. Over the course of about 40 years he has discovered that on average the amount of rain fall has remained the same, but the frequency and the intensity of the rain fall has become more variable. For the most part, Monteverde has received more or less the same amount of rain over the course of a year, however; the rainfall is more infrequent, and more falls when it does rain. Dr. Pounds describes this weather as more variable than ever before. I wonder if similar trends can be observed around the world. Are we experiencing the same trends here in Kansas?