alumni reception - Syracuse Universe Department of Earth Sciences ...

advisor, Professor Linda Ivany, and I have modified
these methods specifically for this project. Our
research involves the application of these modern
techniques to prehistoric whale taxa. For instance, we
are looking at growth banding in the teeth of these
whales. These bands represent changes in the rate of
dental hard tissue accumulation, are associated with
seasonal phenomena, and can thus be used to estimate
age. This technique was developed in the late 1950’s
and is currently the most accurate method of aging
stranded sperm whales, as their teeth grow continually
and thus provide a record of lifespan. My advisor
and I have adapted this method for use in these early
whales with the goal of reconstructing the age makeup
of the prehistoric Atlantic coastal plain populations.
To this end we section the teeth longitudinally to view
banding patterns. We are in the process of exploring
Mandible and teeth of a prehistoric sperm whale (genus:
Physeterula) from the Lee Creek Mine, North Carolina.
Though smaller than their modern relatives, these whales
were probably more deliberate predators, apparently
feeding on fish and smaller whales as indicated by wear
faceting on the teeth. The abundance of remains at
the mine suggests it played some important ecologically
role to these whales.
a new promising technique: micro-computed
tomography (Micro-CT). Micro-CT scanners use X-
rays to take high resolution cross sections of objects,
the X-rays detect minute density differences in the
scanned object which manifest in the images as
discreet features, and these density discrepancies can
then be quantified and graphed. Contiguous growth
bands have significantly different densities; hence
theoretically this technique can be used to count
growth bands and age our whales. Moreover, because
the X-rays can easily resolve the internal features of
the teeth, sectioning is precluded.
We are also interested in tooth chemistry,
which may be used as a proxy for ecology. Teeth
record the conditions at hand during their formation.
Chemical signatures in teeth can represent certain
characteristics of the environment or be indicative
of particular biological and/or behavioral traits.
With the proper tools to extract these signatures and
understanding of their dynamics it is possible to
reconstruct environmental parameters or determine
the biological/behavioral inclinations of an organism.
In this study we are attempting to determine whether
or not these whales were migratory groups, looking
specifically at carbon isotopes.
I am tremendously grateful to all the programs
that are helping to fund, not only this research, but
my scholarship. They are: The Eastern Federation
of Mineralogical and Lapidary Society, The
Paleontological Society’s Stephen Jay Gould Student
Research Grant, the National Science Foundation’s
Graduate Research Fellowship, and The McNair
Scholars fellowship, as well as contributions from
The Syracuse University Office of Research and
the Graduate School. I would also like to thank
my advisor, Linda Ivany, for being a great mentor,
colleague, resource and friend. I again sincerely
extend thanks to all these programs and people,
without which this research would not be possible.
Nathan Graber
I came to Syracuse University to start my
Masters last fall. Since my arrival I have worked
towards completing my thesis research and have
made a great deal of progress towards completing my
sample analysis. For my project I will use (U-Th)/He
thermochronology on apatite as well as DEM analysis,
to study the uplift history of the Frontal Cordillera of
the Andes, near Mendoza Argentina.
I completed my field work, in Argentina, last
January. While there I collected two suites of rock
samples. Each set of samples consists of a vertical
transect spanning approximately 2,500 meters of
elevation change. The samples I collected come from
the Rio Mendoza and the Rio Tunuyan, river valleys.
These samples will help constrain the timing of uplift
by indicating when erosion significantly increased.
This summer has been spent preparing the
samples I collected in Argentina to run helium
analysis. This preparation consists of crushing and
sieving my samples before separating the minerals
on the basis of density, using LST. Finally I will
hand-pick apatite crystals which fit the specifications