With two weeks of our Costa Rica
trip left to go, it was time to start our final research project. My partner
and I chose to work with extrafloral nectaries and their relationship with
ants. Extrafloral nectaries are glands on certain plants that provide ants with
a source for sugar. When these ants occupy the plant, they protect the plant
from herbivores. We wondered whether extrafloral nectary production in
seedlings influenced herbivory and whether extrafloral nectary production in
seedlings was influenced by light intensity.
In order to answer these questions,
we set out into the La Selva forest and located seedlings of the plant Pentaclethra macroloba, which are known
to produce extrafloral nectaries. I struggled to identify the plant at first,
often mistaking it for a fern. However after four days of data collection and
96 seedlings used, identification became second nature.
We attracted ants to the plants by placing
tuna on the leaves. We then checked for any ant presence in the plant for five
hours. Ant presence was used as a proxy to determine if ants regularly occupied
that specific seedling.
We also had to count the number of
extrafloral nectaries on each seedling. Because the seedlings were small to
begin with, identifying extrafloral nectary glands seemed a daunting task.
However we were then introduced to the jewelry magnifying glass, a device that
when worn looks like it’s from the future, but is simply a hands-free
magnifying glass that is worn on the head. This made identifying the glands
much easier and more efficient.
We used a densiometer in order to
measure light exposure in each plant. Densiometers are convex mirrors that are
used to estimate canopy cover overhead. Estimating canopy cover seemed like it
would be a simple task, but I had to hold still with both arms extended in
order to keep the densiometer level and the mosquitoes had a field day taking
advantage of this. One day after data collecting, I counted nine bites on the
back of my hand alone.
Although data collection was time
consuming and took a lot of work, the fact that it took place in the unique La
Selva forest made it an incredible experience. One day I heard thumping sounds
of things falling next to me. After a couple of minutes of this it occurred to
me that Capuchin monkeys overhead were throwing shells of a fruit they were
eating at me. I amusedly watched this happen for a little while until one of
the shells hit me on my shoulder. I decided to hurry up with the plant I was
working on so as to move on. The following day I was lucky enough to spot endangered
spider monkeys swinging around in trees above me. This was only the second time
I had seen spider monkeys on the trip and by far the best view I had of them. I
was amazed at how long their tails were and how much taller they were then the
other monkeys of Costa Rica.
After hours and hours of time spent
in the forest, our results did not produce any significant data, but I built
both a project and experience I will never forget.
This comment has been removed by the author.
ReplyDeleteVery nice initiative has been taken by your student. I would like to share it with QandA staff.
ReplyDelete