André Schmidt
Research Scholar / Postdoctoral Fellow
Ohio University
College of Osteopathic Medicine
Department of Biomedical Sciences
120 Life Sciences Building
45701, Athens, Ohio
United States
Email: schmidta@ohio.edu
Phone: 740-593-0784
Biographical Sketch
1997-1999
Final examination at the Integrierte Gesamtschule “Grete Unrein”
in Jena, Germany
1999-2000
Civilian service at the Clinic for ophthalmology in Jena, Germany
2000-2002
Intermediate examination at the Friedrich-Schiller-Universität in
Jena, Germany
2002-2007
Diploma (Biology), (Title of the thesis: “Locomotion of the shorteared
elephant
shrew,
Macroscelides
proboscideus
(Macroscelidae, Mammalia)“
2007-2010
PhD-Thesis (Title of the thesis: “The effects of substrate diameter
and orientation on arboreal locomotion in rodents“)
Since 11/2010
Postdoctoral Fellow at Ohio University (A. R. Biknevicius` Lab)
Research
My research interests lie predominantly in the functional morphology and comparative
locomotor biomechanics of small to medium-sized mammals. Most studies on
locomotion of small mammals to date have examined movements on horizontal and flat
surfaces. In reality, small mammals must negotiate terrains that consist of numerous
available substrates (fallen logs, branches). I am especially interested in the strategies
used by animals moving on substrates that are smaller than the width of the animal’s
body. For example, are there differences between mammals with- or without prehensile
extremities? Which parameters define the transition between non-climbing and climbing
locomotor modes and which locomotor strategies might be the locomotor strategies of early
mammals? I am also interested in studying individual variability of locomotor adjustments
caused by different environmental demands placed on the locomotor apparatus (e.g., substrate
orientation).
To answer these questions I have combined the traditional techniques such as highspeed normal light, x-ray videography and substrate reaction force measurements in
various small to medium sized mammals.
For my diploma thesis I studied the
treadmill locomotion of the round-eared
elephant
shrew
(Macroscelides
proboscideus, Macroscelidea, Mammalia).
The goal of this study was to investigate
the effects of different limb proportions
on basic principles of locomotion in small
mammals. The results show that Macroscelides display the same locomotor
adjustments as other small mammals, despite hindlimbs 25% longer than the front
ones. A striking feature in the locomotion of this elephant shrew is the use of a
“unusual” footfall pattern, where one limb is sustained in a constant bent position
during the stance phase of the contralateral limb. Some of the results were presented at
the 8th International Congress of Vertebrate Morphology (ICVM) and 100th Annual
Meeting of the German Zoological Society (DZG).
For my PhD thesis (April 2007 – August 2010) I continued with kinematic analyses
assisted by force plate measurements to investigate the effects of substrate diameter and
orientation on arboreal locomotion in rodents. The thesis was embedded in a
multidisciplinary
project
with
biologist
and
engineers
called
“Inspirat”
(www.Inspirat.de). The aim of this project was the development of a climbing robot
based on biological paradigms.
My PhD thesis consists of the individual parts that are published (study I), and those
which are currently in press (study II & III).
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1st Study – Arboreal locomotion in rats – the challenge of maintaining stability.
This study dealt with the “feat of
moving”
on
small
horizontal
branches in a terrestrial mammal: the
common rat (Rattus norvegicus). In
order to maintain dynamic stability
during branch locomotion the rats
displayed locomotor adjustments that have been observed previously in other
clawed mammals (e.g., lateral sequence gaits, high velocities, similar contact
times and peak vertical forces in forelimbs and hindlimbs). The results indicate,
however, that clawed mammals and primates share several behavioral adaptations
(e.g., reduction of peak vertical oscillations and side-to-side fluctuations) due to
similar biomechanical constraints of small branch locomotion. One of the most
interesting findings was the increase in spine movements as substrate diameter
decreased. Read more…
2nd Study - Functional differentiation of the trailing and leading forelimbs during
terrestrial and arboreal locomotion in the European Red Squirrel (Sciurus
vulgaris, Rodentia).
This study was conducted in order to test
for differences in kinematics (e.g., 3D
joint angles) and dynamics of the first
(trailing) and second (leading) forelimb
during
locomotion
on
a
terrestrial
substrate and a horizontal branch. The
results reveal that trailing forelimbs
function exclusively as
shock-absorbing elements during small branch locomotion whereas a high-level
of stiffness characterizes the leading forelimb. These differences in limb function
are discussed in terms of an increase in stability, in particular on compliant
arboreal substrates. Read more…
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3rd Study - The kinematic consequences of locomotion on sloped arboreal
substrates in a generalized (Rattus norvegicus) and a specialized (Sciurus
vulgaris) rodent.
The aim of the study was to determine which locomotor parameters the rat and
the European red squirrel modify in response to substrate orientation of 30°
and 60°.
The data were compared
with data pertaining to horizontal
small branch locomotion captured in
study I and II. Both species differ
significantly in their preferred gait and
therefore in their travel speed but numerous locomotor adjustments were
surprisingly similar, perhaps due to the biomechanical constraints during
locomotion on inclined small branches. The results of this study improve our
understanding of climbing and support previous assumptions of highly
standardized limb positions …
Since November 2010 I have been a Postdoctoral Fellow in the lab of Audrone
Biknevicius at Ohio University. Ongoing projects include the individual differences in
the locomotor performance of degus at different substrate orientations.
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Publications
In peer-reviewed Journals
Andrada, E., Mämpel, J., Schmidt, A., Fischer, M. S. and Witte, H. (2010).
Biomechanical analyses of rat locomotion during walking and climbing as a base for the
design and construction of climbing robots. In: Brebbia, C. A.; Carpi, A. (Ed.): Design
and nature V. Comparing design in nature with science and engineering. Southampton:
WIT (WIT transactions on ecology and the environment).
http://library.witpress.com/pages/PaperInfo.asp?PaperID=21166
Schmidt, A. and Fischer, M.S. (2010). Arboreal locomotion in rats – the challenge of
maintaining stability. J. Exp. Biol. 213, 3615-3624.
http://jeb.biologists.org/content/213/21/3615.full.pdf+html
Schmidt, A. (in press). Functional differentiation of the trailing and leading forelimbs
during terrestrial and arboreal locomotion in the European Red Squirrel (Sciurus
vulgaris, Rodentia). Zoology
Schmidt, A. and Fischer, M. S. (accepted) The kinematic consequences of locomotion
on sloped arboreal substrates in a generalized (Rattus norvegicus) and a spezialized
(Sciurus vulgaris) rodent. J. Exp. Biol.
In edited Volumes
Witte, H., Fischer, M.S., Karguth, A., Mämpel, J., Schmidt, A., Trommer, C., Schilling,
C., Krause, C., Andrada, E., Stubenrauch, M., Fetter, R., Voges, D., Lehmann, L. and
Schmidt, M. (2008). Zur Technischen Biologie des Kletterns. In: Kesel, B. & Zehren,
D. (eds.) 4. Bremer Bionik-Kongress - Tagungsbeiträge, “Bionik: Patente aus der
Natur” (www.gtbb.net) pp. 196-206.
Abstracts
Schmidt, A. and Fischer, M. S. (2007) Locomotion of the short – eared elephant shrew,
Macroscelides proboscideus (Macroscelidea, Mammalia): effects of elongated hind
limbs. J. Morphol. 268, p. 1131.
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http://onlinelibrary.wiley.com/doi/10.1002/jmor.10589/pdf
Presentations - Talks
Schmidt, A. (2008). Cineradiography – the look inside. 1st Graduate Meeting Morphology “Form & Function” at the 101. Annual Meeting of the German Zoological
Society (DZG) in Jena, Germany.
Schmidt, A. (2009). Arboreal locomotion in the European red squirrel (Sciurus
vulgaris). 5th International Colloquium on Arboreal Tree Squirrels – Kamloops, Canada.
Schmidt, A. (2009). Arboreal locomotion in rats – the challenge of maintaining
stability. 102th Annual Meeting of the German Zoological Society (DZG) in
Regensburg, Germany.
Presentations - Poster
Schmidt, A. and Fischer, M. S. (2007). Locomotion of the short – eared elephant
shrew, Macroscelides proboscideus (Macroscelidea, Mammalia): effects of elongated
hind limbs. 8th International Congress of Vertebrate Morphology (ICVM) in Paris,
France.
Schmidt, A. and Fischer, M. S. (2007). Limb proportions and their effects on
locomotion
in
the
short-eared
elephant
shrew,
Macroscelides
proboscideus
(Macroscelidea, Mammalia). 100th Annual Meeting of the German Zoological Society
(DZG) in Köln, Germany.
Schmidt, A., Krause, C., Schmidt, M. and Fischer, M. S. (2008). Climbing robots –
inspired by nature. 101th Annual Meeting of the German Zoological Society (DZG) in
Jena, Germany.
Andrada, E., Schmidt, A., Köhring, S., Mämpel, J., Fischer, M. S. and Witte, H. (2009).
The effects of substrate inclination on torque patterns in rats. 3rd International
Symposium on Mobiligence in Awaji, Japan.
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Schmidt, A. (2011). Functional differentiation of the trailing and leading forelimbs
during terrestrial and arboreal locomotion in the European red squirrel (Sciurus
vulgaris, Rodentia). Annual Meeting of The Society for Integrative and Comparative
Biology (SICB).
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