Indiana Academy of Science
North American Plant
PAST - Paleontological
Tilia & TiliaGraph Pollen
Some Selected Research Projects
Conducted in My Laboratory
Applications of perch operculum morphometry to palaeolimnological
We are examining fossil opercula of yellow perch to compare growth patterns of fish
that lived 6000 years ago (early Holocene of central Michigan) with those of modern
day populations. This research has been submitted for publication and is in review. A
more detailed summary will follow once the manuscript has been published.
Discovery of 30,000-year-old spruce wood from central Indiana.
We are examining organic remains recovered from a depth of 129 feet during drilling
of a well in Vermillion County, Indiana. The remains included fragments of wood
that were radiocarbon dated (using accelerated mass spectrometry) at 30,000 years
old. There are very few dated records of organic material for this time period in
Indiana. Examination of thin sections of the wood in various planes indicates that
most of the fragments were spruce. One fragment had qualities similar to tamarack,
but the observed characteristics are not conclusive. This data contributes to our
understanding of Wisconsin-age climates and glacial chronologies. The research has
been accepted for publication in the American Midland Naturalist and is in press.
An ecological characterization of the inland mangrove swamps of Grassy Key,
We are examining the food web of land-locked mangrove swamps on Grassy Key,
Florida. These wetlands are often highly saline, low in dissolved oxygen, and hot due
to evaporation and lack of tidal and wave activity. As a result, these communities are
like "aquatic barrens." However, many species of killish (Cyprinodontidae) thrive
there. Those involved in the research are determining the diet of the killifish as well
as surveying the biota of these wetlands so they can develop a food-web to
characterize the ecological interactions there.
Palaeoecology of the Pipe Creek Sinkhole (Tertiary: Hemphilian) in central
In 1997, when the Pipe Creek Sinkhole was discovered by workers at Irving
Materials, Inc., in Grant County, Indiana, it was the first Tertiary-age deposit (5
million years old) ever discovered in the eastern interior of the continental United
States. The sinkhole contained remains of extinct rhinoceros, camel, bear, wolf,
giant tortoise, rodents, as well as turtles, snakes, and a variety of plant remains. We
have been working on this deposit with scientists from Indiana-Purdue University at
Fort Wayne since the discovery of the sinkhole. Our lab is in charge of the botanical
remains. So far, we have identified a number of wetland species (Chara,
Polygonum) as well as trees (Sycamore, Beech, Poplar). A summary of the initial
discovery was published in the American Midland Naturalist in 2001. Those
conducting the research are currently working on more detailed analyses involving
the sedimentary environment, as well as additional taxonomic work involving
Scanning Electron Microscopy.
The role of dead and downed wood as summertime refugia for amphibians in a
west-central Michigan forest.
Forest canopy structure and litter (especially dead and downed wood) can be very
important elements in determining biodiversity of a forest ecosystem. Forest
management practices that result in the removal of dead wood might negatively
affect the ecosystem. We are examining one aspect of the role dead and downed
wood has on biodiversity: its role as amphibian habitat during the summer months.
We are collecting data on the stage of decay, length, diameter, and summertime
amphibian inhabitants of dead and downed wood and using statistical analyses to
indicate which characteristics of the downed wood are most favorable to amphibians.
Spatial and temporal variation in subfossil assemblages from peat cores taken
in close proximity.
The fate of Chamaedaphne calyculata in the surface sediments of a
west-central Michigan Sphagnum bog.
We are studying Guenther Bog at Hillsdale's G. H. Gordon Biological Station in
Luther, Michigan. On one project we are identifying and quantifying macrofossils
from 10-cm intervals from three separate cores and using multivariate statistical
analyses to determine how appropriate it is to base palaeoenvironmental
reconstructions on a single core. On a second related project, we are intensively
sampling leatherleaf macrofossils (an important ecological indicator species) from the
surface peat of the bog and using degree of fragmentation and SEM analysis to see
how persistent leatherleaf is in fibrous Sphagnum peat.
Reconstructing Palaeoenvironments in the context of extinct ice-age
We work very closely with the research staff at the Indiana State Museum. Our lab
is responsible for analyzing microfossils and plant macrofossils for reconstruction of
the palaeoenvironment in which things like mastodonts and mammoths lived (and
died). We are actively engaged in studying 7 mastodont localities; 6 in Indiana and 1
in Michigan. Most of these studies focus on macrofossil and sediment analysis, but
one mastodont had preserved intestinal contents. We are currently writing a
manuscript for publication that characterizes the diet of that animal. Another site, the
Buesching Locality, has both mastodont and a fossil beaver dam. In addition to the
standard sediment analysis, we plan to study the beaver works as a source for
dendrochronology data and possible palaeoclimatic information.
The history of Celery Bog: Palaeoecology driven by community interest.
Celery Bog in West Lafayette, Indiana, has been the source of much controversy.
Most of the controversy arose when a proposal to build a Wal-Mart next to the
wetland was submitted. Environmental advocates were concerned about parking lot
chemicals (oil, salt, etc.), washing into and harming the wetland. Old-timers then
indicated that the wetland was not natural, recalling that they had farmed it in the
30's, and it only recently became wet. Scientists argued that the wetland was present
prior to farming, was then drained for farming, and then when farming stopped in
the '40's, the drainage tiles clogged and the area reverted to wetland. The City of
West Lafayette, then provided a grant to Dr. Swinehart and Dr. Jonathan Harbor of
Purdue University to solve the controversy using palaeoecological methods. Results
show that the area was a lake 13,000 years ago and had slowly filled and became a
wetland prior to human settlement. It was not only a wetland, but a very rare type of
wetland (for that part of Indiana, anyway); a Sphagnum bog. Wal-Mart was
approved, but they donated money for the building of a public educational center.
Analysis of the core and reconstruction of the paleoenvironment is still underway and
will be submitted for publication.
|This page highlights and summarizes the research conducted by myself (Dr.
Anthony Swinehart) and my students. My laboratory is located on the third floor of
Hillsdale College's Dow Science Building (click on thumbnails).
The Palaeoecology Laboratory at Hillsdale College
Research in my lab has included a variety of topics in aquatic ecology. However, the
major focus is on wetland palaeoecology and ecological succession of aquatic
ecosystems. My students work very hard on their research, and many have received
awards at scientific meetings for their research presentations. Some of my students
are currently involved in preparing manuscripts for publication. Graduates receive
master's and doctoral degrees in biology at top universities or gain employment
immediately after graduation. If you are a high school student interested in aquatic
ecology or palaeoecology, please take a moment to peruse this web page and
associated links. If you have any questions, or would like to schedule a visit to
Hillsdale and meet with me, please e-mail me.