Tuesday, November 24, 2015

The Answer Lies in the Connections


For the longest time, the direction that biodiversity conservation has been taking is the conservation of species and the habitat that they live in. This is exemplified by organizations such as the International Union for Conservation of Nature (IUCN), which categorizes species according to their abundance and levels of extinction threats, allowing conservationist to direct their efforts to specific groups of organisms.
A quick refresher of elementary school science and high school biology reminds us that organisms do not live in isolation but are instead part of an immense web of interactions. When these interactions are intact, ecosystems are healthy and dynamic, able to respond to fluxes in environmental conditions and population changes. Earlier this semester, we explored a novel concept that could potentially change the direction of conservation, that is focusing on preserving interactions between species rather than species themselves. While recognizing that this was an interesting concept with conservation implications, I did not think too much into it and it remained just as a lingering thought at the back of my mind. Roughly a month and a half later, after spending time in various terrestrial and marine ecosystems, this dormant thought sprung back into life as we explored how forests were shaped through the processes of pollination and seed dispersal. These processes are key in the reproductive cycle of plants, which form the majority of biomass in all forests. With a huge diversity of plants in the forest, each species needs to ensure its pollen is delivered to a conspecific, a task that is by no means easy. Fortunately, through geological time, evolutionary forces have directed an interplay between plants and animals, with the former providing nutrients to attract the latter to provide pollen delivery services. Studying pollination syndromes at Monteverde was definitely an interesting look into how unique floral parts are, allowing plants to be matched up with very specific pollinators. In the same way, animals play a huge role in facilitating the dispersal of seeds away from parental plants, reducing intraspecific competition and reducing density dependent mortality. Without dispersers, even pristine looking forests are deemed “empty” and unlikely to display future recruitment and sustained growth.
While nature has programmed redundancy into this web of interaction through thousands of years of evolution, we are proceeding closer and closer to a tipping point as human development tears away at many of these crucial links. It is perhaps time for us to look at how interactions can be stabilized among members of the ecosystem, focusing on the connections rather than the nodes. This will give us a much needed push in ensuring the remaining natural areas are sustained well while we continue to direct efforts in restoring altered habitats and ecosystems. 
Donovan Loh
Duke University

Frog Friend for Life

Six months ago I would have never given a second thought to a little green-brown amphibian hopping by or croaking in a nearby stream; now, after many night walks, day trips, and a week at San Gerardo Biological Station in El Bosque Eterno de los Niños, these creatures have become some of my favorite animals.
            At San Gerardo we learned about amphibian taxonomy, frog calls, and the global amphibian die-off in the 80’s and 90’s. I remember going out into the swamp at La Selva one night and hearing so many calls and layers of sound, yet being unable to identify any of the sources, and now I know that these were choruses of frog calls, often triggered by a few leaders within each species. I spent a week learning about aposematic coloration in lepidopteran larvae for my independent project, and now I know that aposematic signals can also take form as calls and promote Mullerian/Batesian mimicry through sound pathways. I knew that both female and male Oophaga pumilio participated in caring for their young, but I didn’t know that there were once gastric brooding frogs that would swallow eggs and eventually throw up babies. Frogs have come up with amazing adaptations that differ vastly from species to species. These creatures that rarely crossed my mind before now blow my mind again and again as I learn more about them. I thus found myself strangely empathetic to their plight during our discussion about the sudden, global amphibian decline. When coming up with ideas of what caused the species drop-off, people threw out some funny ones, such as “alien abduction”, which generated some much-needed laughter. But our topic was so dark that I found the welcomed laughter was almost harsh and a little jarring, and I was slightly taken aback by my reaction, surprised by how I cared.
            Images of the wide, captivating eyes of the critically endangered yellow-green Agalychnis lemur came to mind and I felt impassioned to determine what caused their death. My attitude towards amphibians is just one of many things that have been transformed for me during this program. After seeing/learning about over thirty species of fantastic frogs and toads, I’ve gained a deeper-seated desire to protect them. After seeing gorgeous wet, dry, pre-montane, Páramo forests, I’ve learned to despise deforestation. After my week at the San Geraldo station, I realized that I’ve changed want to try my best to practice conservation, wherever my future leads.
Jeanne Shi
Duke University

Warrior Plants

During class one day (and by class, I mean hiking through the forest and learning about what we see), our professor Mau told us to lay on the ground of the Children’s Eternal Rainforest in Monteverde and pretend to be seedlings. Um okay…? We were all confused, but we went along with it.
While laying in the misty forest, I thought about what it would be like to have to survive as a seedling. It would be like being a warrior. When warriors hit the battlefield, nothing gets in their way. It’s win, or die trying. Plants are exactly the same.
If plants and warriors aren’t exactly synonymous in your head, I understand. Plants are serene, beautiful, and tranquil. Warriors are violent, brutal, and, well, basically everything opposite. However, though it may seem incongruous, the forest is a ruthless battlefield. Every day, animals, bugs, and plants are fighting to survive. And when I say fighting, I mean FIGHTING. I know, you’re thinking, “Okay Mackenzie, I get it for animals which can have claws and fangs. Or bugs, which can sting and bite. But plants? Plants don’t fight.”
Oh yes, plants fight.
Sometimes it’s obvious, like if the plant has modified parts creating giant prickles, spines, or thorns. Sometimes it’s a little more hidden, like if the plant is inedible or poisonous. But a lot of the fighting plants do goes unseen. Unless you know what you’re looking for.
Forests are packed. We always talk about how great it is to have so many diverse individuals in such a small area, but what do you do if you’re a new seed trying to grow?
Let’s say you’re a newly dispersed seed. Where were you dropped? A stream? What about on another tree? Did you land on another plant’s roots? If you answered yes to any of the above, you’re not growing. Your odds of being the only plant falling on a patch of soil suitable for growing is slim, but let’s say that you’re a lucky seed and you find a great patch of soil. What’s next?

Sun. This one’s tricky. In a forest, only about 2% of the sunlight that hits the canopy makes it to the ground. For some plants, that’s nowhere near enough. Perhaps this is where your story ends. However, on occasion you get lucky and find yourself in a light gap. Light gaps are made when a branch or a tree falls in the forest, allowing light to reach the forest floor. The second the light gap is made, the true warrior plants step in. The competition is brutal. The gap is filled with seeds trying to take over—some are new arrivals; some have been waiting for the right conditions for years. But all of the seeds want to get the best patch of soil, the most sunlight, and the most nutrients to grow tall as fast as they can. The race is on! Whichever plant grows tallest and strongest the fastest shades out the other plants and is crowned victorious. The rest die. So as a seedling sitting on the forest floor in Monteverde, did you win?
Mackenzie Coden
Northwestern University