When I went to college I thought I was going
to study biology, but I was also interested
in environmental science, and I started taking
some geology courses. And the thing that really,
really intrigued me about geology was the
timescales, the amount of time that a lot
of these processes take. Paleontology was
a really great way of combining my earlier
interest in biology with my newfound interest
in geology. In particular I was really interested
in the early evolution of animals, and the
fossil record of course is the way to directly
study that. The reason that I study trilobites
is because they're really useful for the kinds
of questions I'm interested in asking. A trilobite
is an arthropod. Arthropods are the group
that contain insects, crustacea, spiders.
But trilobites are completely extinct. They
lived in the ocean they lived all over the
world and so they're preserved all over the
world, and they live for a really long time.
They were around for 250 million years. Trilobites
are one of the first types of animals to show
up in large numbers in the fossil record.
The reason for this is that their exoskeleton
had a lot of minerals in it. And they preserve
really well. So one really cool thing about
trilobites is that like insects, they molted
throughout their lifetime. And all of those
molts are preserved in the fossil record.
Which means we can actually go back and look
at how they change during development, how
how they changed during their lifetime. And that
gives us a lot of information about how changes
during development might influence long term
evolution. For my research I'm really interested
in how species evolve. How and when species
evolve. Part of that is just reconstructing
the tree of life of trilobites. And part of
that is looking at how specific physical characteristics
change over time. So one of the methods I
use to describe physical characteristics in
trilobites is geometric morphometrics. And
basically what we do is we pick a bunch of
points that overall represent the shape of
the part that we're interested in. So for
example one of those points might be the place
where the eye meets the rest of the exoskeleton.
And that series of points together, that configuration,
is a quantitative description of the shape.
Researchers have used verbal descriptions
to compare different species. But this method
lets us describe those species in a quantitative
way. I've done a lot of fieldwork in Nevada
and Utah. And working in the desert is great
because there's very little vegetation. And
you can basically just walk up a hillside
and sample at different rock beds as you walk
up. Essentially walking through time sampling
as you go. It's great being out in the field
and collecting new material and discovering
new things, but the same discoveries can actually
happen in the Museum as well, opening up old
drawers and finding specimens that were collected
years ago, probably for a completely different
purpose, and realizing that it's the perfect
thing for the study that you're working on
right now.
