During my first two years
in Chile I worked primarily in the field. This year however, with the exception
of one quick week in the field, I’ve been doing all my work in the laboratory.
The field and the lab both have their advantages and disadvantages, pluses and
minuses, ups and downs. My experience working in both environments has caused
me not to pick a favorite, but rather to conclude that the strongest research
approach contains both lab and field components. In this post, I’ve identified
five major research concerns; experimental control, ecological relevance, animal
maintenance, expenses, and working conditions. For each research concern, I’ve
written a short discussion comparing and contrasting the relative benefits of lab
and field approaches (note: this post is mostly geared towards those that work
with vertebrate animals).
Experimental
control
There are two types of
things you want to control in an experiment; variables and sampling
opportunities, and the lab clearly wins in both categories. In the lab, most
variables can be controlled and sampling opportunities are only limited by
experimental design or physiological limitations. In the field, however, there
is only so much control researchers can assert over certain variables. For
example, weather is pretty much uncontrollable. Sure, you can put a heating pad
in a nest box or you can water an experimental plot during a drought, but
that’s pretty insignificant in comparison to a temperature and humidity-controlled
animal room. And as for sampling opportunities, oftentimes field researchers
are subject to the whims of their animals.
During
my field research there were several variables I wish I could have controlled.
For example, because degu pups are born in underground burrows and do not come
aboveground until three weeks of age, there was no way for me to measure or
sample the pups during this time. Additionally, because female degus live in
social groups and raise their offspring in communal burrows, there was no way
for me to determine which pups belonged to which mother within a social group. Using
genetic information could have solved this problem, but the genetic tools for
degus are still being developed.
For
my lab experiment, these problems don’t exist. I know the exact day my pups
were born, who their mother is, and how much they weighed at birth. I can now
weigh and measure the pups and mothers as frequently as I need to, and I can
also observe the behavior of my degus by videotaping them whenever I want. This
was another thing I couldn’t do in the field- because degus live underground,
there was no way for me to see if my experimental treatment was affecting the
level or quality of maternal care. In conclusion, the lab is a better
environment for experiments that require a lot of controlled variables or
specific sampling points. This comes at a cost, however, which brings me to my
next research concern:
Ecological
relevance
As
soon as you bring an animal into an artificial environment you alter its
behavior and physiology. This can be exemplified by the struggles of captive
breeding programs for endangered animals; over the years researchers have been
able to determine necessary stimuli conducive to breeding, but there still are
difficulties even with the best-studied species. In the lab, we know that degus
will allonurse (meaning, a mother will nurse pups other than her own), but is
this true in the field? Do degus only allonurse in the lab because they have
plenty of food? Or maybe because of space limitations, it’s too difficult to
keep litters of pups separate? Until we can put cameras in real degu
burrows, we can only assume that degus allonurse in the wild.
The
point is that animals may behave differently in the lab because there may be
significant factors that we, as humans, are not aware of. Animals may perceive
or be more sensitive to certain wavelengths of light (unlike us, degus can see
in the UV spectrum), odors, or noises. What may seem innocuous to a human may
be stimulating or frightening to another animal. A combination of several
factors ultimately creates an environment that is totally different and
separate from an animal’s natural living conditions.
However,
there are ways to make laboratory experiments more ecologically-relevant. Some
labs, for example, house their animals in outdoor enclosures. This limits the
control of things like temperature and weather, and it may also be harder to
sample or observe animals in such a large space, but it does allow animals to
experience more natural conditions and cues. Experiments can also be more
ecologically-relevant by using stimuli that animals would typically experience
in the wild. For example, if you want to study the stress response of an
animal, you could use more “natural” stressors such as cold, rain, or
unpredictable food availability rather than something artificial like playing a
loud radio for 30 minutes. Lab and field experiments aren’t necessarily
separate things, and it’s up to researchers to decide where their experimental
design will fit best on the continuum between experimental control and
ecological relevance.
Animal
maintenance
Currently,
I’ve been spending a lot of my time cleaning degu cages. I don’t mind doing
animal husbandry, but at times I do feel a little under pressure because I know
that I’m the sole person responsible for the health and wellbeing of my
animals. It’s a responsibility I take seriously, so I make sure to give my
degus the best care possible. The level of responsibility is different in the
field, however. Besides checking traps often and giving degus an extra handful
of oats while they’re waiting to be returned to their burrows, I can pretty
much let the degus take care of themselves. So in terms of animal maintenance,
the field usually wins, especially because animal care costs can be rather
high, which brings me to my next point:
Expenses
To successfully carry out
experiments, researchers need to pay for equipment, supplies, and field or lab
assistance. If the experiment will take place far from home, researchers may
also need to pay for travel, housing, and other various costs such as permits,
shipping expenses, etc. Both lab and field experiments can be expensive- it
really depends on your experimental design and whether you already have some of the necessary equipment.
For me, it was the really
the international component that made my experiments expensive. Both my lab and
field experiments required me to pay for plane tickets and housing costs, which is
something a researcher wouldn’t normally have to worry about. As for lab and
field-specific expenses, they ended up being about the same; for my field
experiment I had to rent a truck and for my lab experiment I needed to pay for
animal care during the nine months I was back in the U.S. Equipment costs were
more expensive for the lab experiment (terrariums, video cameras, etc.) but
only because I had access to pre-existing equipment for my field experiment
(animal traps, radiocollars, etc.). So, in the end, neither the lab nor the field was more
expensive than the other, and the total cost of an experiment is really
determined by experimental design.
Working
conditions
I
hate getting up early. Maybe not as much as some people, but when the alarm clock
goes off and it’s still pitch-black outside, my inner voice grumbles a steady
stream of obscenities as I get out of my warm, cozy bed. Now, you might think that
getting up early is a burden that only field researchers carry, but that’s not always
true. For my current lab experiment, I’ve been getting up around 6am every day
for two reasons: 1) in order to be consistent with my field experiment, I’m
trying to collect blood samples before 9am and 2) the Santiago metro becomes a
living hell during rush hour, and in order to keep my sanity I have to catch
the subway or bus before 7am. While I did have to wake up even earlier when I
was doing field work (4:30am, woo-hoo!), I would allow myself to take off one
day per week. For my current lab experiment, though, there’s something I have
to do every, single, freaking morning. So when it comes to early mornings and
total work hours, neither the lab nor the field wins.
Fieldwork
can sometimes be miserable. It can be freezing cold or baking hot, or the dew from the
grass can make your boots and pant legs soaking wet. Opening 150+ traps in the
dark is no fun, either, nor is hauling traps up and down a big hill (or small
mountain, it depends on your perspective). In all truthfulness, my fieldwork is
relatively tame (one of my friends works in a very hot, humid forest where she
spends several hours a day tramping up and down steep hills, all while looking
out for venomous snakes) so I really shouldn’t complain. But, nevertheless, I’ve
had my share of trials and tribulations. One time I had to go to the hospital
because of a really bad hand rash. One time an opilion (a very large, creepy arachnid-
see photo) crawled up my pant leg. I’ve also fallen down hills, tripped over
rocks, and had serious wardrobe malfunctions (i.e. ripping open the seat of my
pants).
But I would never give up
field work for anything. I love being outside all day, and my time in the field
has allowed me to witness and experience so many cool things. I’ve seen
moustached turcas (see picture) carrying grubs in their beak, running to and
from their nests. I’ve seen an iguana eat an akodont (a small, mousey-like
rodent) and an eagle knock a caracara (a small bird of prey) out of the sky. One
of the coolest things I saw was a wasp trying to drag a paralyzed tarantula through
one of my degu traps. These wasps are called “tarantula hawks” and spend their
days zooming over the ground, searching for tarantulas. When they find a
tarantula, they deliver a powerful string which doesn’t kill the tarantula but
effectively paralyzes it. The tarantula is then dragged to the wasp’s nest
where it is eaten by the wasp’s larvae after they hatch.
So while maybe the lab is more comfortable, the
field is definitely more fun. And when stuff doesn’t work out or when you make an
experimental mistake, if you’re in the field you can reason that “Well, at
least I got to spend the day outside.” (this quote is attributed to Dr. Sara O’Brien).
Wherever I end up after grad school, I’m sure I’ll be doing field research!
The opilion. |
My favorite bird- the moustached turca! |
The tarantula and the tarantula hawk. |
No comments:
Post a Comment