26
May 2001 - 4 August 2001
A total of 18 students were selected
to participate in the 2001 session of the Research
Training Program including 3 international
students representing Brazil, Canada, and Yugoslavia.
Schedule
of Events |
Poster |
Program
Summary
Student
Abstracts |
Photo
Gallery
The
Ethics Discussion
Research
Training Program
Project Summaries
(Click on
the name below to go to the individual project
summary page.)
Meet
the 2001 participants
and read about their research projects
Back
row (left to right)
Katarina Topalov, Anastasia "Stacie"
Poulos, Matt Friedman, Michael Holcomb, Trevor
Krabbenhoft, Jeff Saarela, Laura Holladay,
Yana Reid, Alexandre Ribeiro.
Front
row (left to right)
Sharon Wilson, Dawn Stodden, Erin DiMaggio,
Ainsley Seago, Marita Davison, Abigail "Abby"
Knee, Yolanda Chacon, Courtney Porreca, Shannon
Schwaller, and Julianne Rowehl.
In
addition to our research reports, be sure to
check out our personal summaries
about our summer at the Smithsonian.
|
- Gender:
Female.
- Ethnicity/Race:
Hispanic.
- Institution:
New Mexico State University.
- Status:
Sophomore.
- Major:
Biology.
Career
Goals:
After graduate school achieve a career
in either Ornithology or Medicine.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
Update
- December 2002: Yolanda is finishing an
undergraduate degree at New Mexico State
University. She recently presented a poster
explaining the results of her RTP research
at The American Biomedical Research Conference
for Minority Students. She plans to attend
graduate school and maybe even study birds
- much to the delight of her RTP research
advisor Carla Dove!
|
Yolanda
J. Chacon
Project
Advisor: Dr. Carla J. Dove, Department of Systematic
Biology, Division of Birds.
Project
Title: Microscopic
feather character analysis of the cranes, rails
and allies (Avian Order: Gruiformes).
Research
Abstract: Twenty-six feather characters
(both micro- and macroscopic) of 12 species
of birds within the avian order Gruiformes (cranes,
rails and allies) were described, photographed
and then investigated using parsimony analysis
to determine if feather characters in this group
of birds provide phylogenetic signal.
Feather
characters were analyzed separately and in combination
with mitochondrial 12S rDNA data (Houde, MS
in prep) and resulting trees were compared.
Strict consensus of two trees obtained from
feather characters (TL= 91, CI= 0.68, RI= 0.59,
RC= 0.40) shows that these characters have indices
comparable to the tree obtained from molecular
characters (TL= 2147, CI= 0.53, RI= 0.38, RC=
0.20). However, the resulting feather and DNA
trees agree only in some terminal taxa relationships.
Although
the rails (Rallus, Laterallus) are sister
to each other according to both datasets, the
DNA characters place Sungrebe (Heliornis)
as the closest relative to rails whereas the
feather characters place Mesitornis (roatelo)
as the sister to that group. The strict consensus
feather trees and the DNA tree are congruent
in the relationship of Cariama (seriema)
to Choriotis (bustard). Grus (crane)
and Aramus (Limpkin) are in the same
clade according to both trees, however feather
characters place Heliornis within that
clade instead of Psophia (trumpeter)
as is suggested by DNA characters. The DNA tree
does not resolve the status of Mesitornis
but rather places this taxon as an outgroup
to the main clade. A single tree of all combined
characters resulted in a tree with indices of
TL= 2086, CI=0.54, RI= 0.42, RC=0.23 and was
more similar to the tree obtained from the DNA
characters.
Although
more research is needed on the feather characters
in this group of birds, this study provides
evidence that feather characters produce trees
that cluster into 'natural groupings' in parsimony
analysis and supports the idea that these characters
can be useful for feather identification and
phylogenetic analysis.
Publication:
Chacon, Y.J, and Dove, C.J, In Prep.
(To be submitted in summer 2002) Microscopic
feather character analysis of the cranes, rails
and allies (Order: Gruiformes). Proposed for
publication in the Wilson Bulletin.
Project Summary |
Letter
of Gratitude
|
-
Gender:
Female
- Ethnicity/Race:
White
- Institution:
University of Michigan.
- Status:
Freshman.
- Major:
Geology.
Career
Goals:
After obtaining a Ph.D. in Geological
Sciences, pursue a career as a volcanologist.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
Update
- December 2002: Erin is still an undergraduate
student at the University of Michigan.
She spent the summer of '02 serving an
internship with NASA at the Jet Propulsion
Lab in Pasadena, California, specifically
focused on the Martian Exploration Program
with Arwen Vidal (1999).
|
Erin
N. DiMaggio
Project
Advisor: Dr. Sorena S. Sorensen, Department
of Mineral Sciences.
Project
Title: Evidence for Feldspar
Replacement in Altered Metamorphic Tuffs in
the Duck Lake Volcanic Suite
Research
Abstract: Metavolcanic rocks can be powerful
tools for documenting the complex histories
of multiple episodes of fluid-rock interaction
in long-lived arc crust. The Duck Lake area
of the Mammoth Crest, eastern California, is
part of a lithotectonic assemblage exposed along
the eastern front of the Sierra Nevada. Meta-rhyolite
tuffs at Duck Lake show complex K, Na, and Ca
systematics and disequilibrium feldspar phase
relations that reflect a superposed history
of contrasting metasomatic systems.
Using
cathodoluminescence and mineral and whole rock
compositions, a reconstruction of the metasomatic
system's history was prepared. Cathodoluminescence
petrography shows igneous phenocryst and ground
mass feldspar completely replaced by near-end-member
orthoclase (Or>95 after sanidine) and or
albite (Ab>95 after plagioclase).
These
textures resemble those of nearby meta-tuffs
in the Ritter Range Pendent (on strike, 20 km
NW) and of unmetamorphosed Tertiary tuffs (Creede,
CO, Socorro, NM) that have undergone low temperature
K- or K/Na- metasomatism. In those rocks alkali
alteration occurred soon after deposition. These
early features are overprinted by Ca-metasomatism
that is manifested by calcite veins and grossular
+ epidote veins with calcic plagioclase (An80-100)
vein envelopes. The early pseudomorphs of phenocrysts
and groundmass feldspar are replaced by calcic
plagioclase in this event. Whole-rock geochemistry
shows concomitant gains of Ca and Sr and loss
of Na. CaO/Na2O for tuff samples ranges to 13,
a value >6 times that of unaltered ashflow
tuffs. K/Na values for Duck Lake tuffs are similar
to those seen in the Ritter Range, Creede, and
Socorro, but display distinct slopes on plots
of K/Na versus Rb/Sr.
Textures
indicate that Ca was sourced by hydrothermal
fluid derived from carbonates, probably locally.
The Ca-rich silicate veins cut metamorphic fabrics
that Tobisch et al. (2000) regionally attributed
to batholith emplacement, indicating Ca-metasomatism
occurred during retrograde phases of contact
metamorphism. Evidently, as seen in many ore
deposits, cooling contact metamorphic systems
can be accompanied by large amounts of mass
transfer.
Project Summary |
Letter
of Gratitude
- Gender:
Male.
- Ethnicity/Race:
White.
-
Institution:
University of Rochester.
- Status:
Junior.
- Major:
Biology and Geology.
Career
Goals: After obtaining a Ph.D.
in paleontology, achieve a career as a
university professor conducting research
on extinct and extant fishes.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
|
Matthew
S. Friedman
Project
Advisors: Dr. James C. Tyler and Dr. G. David
Johnson, Department of Systematic Biology, Division
of Fishes.
Project
Title: A putative lampridiform
from the Oligocene of Peru.
Research
Abstract: A nearly complete
fish skull and two associated vertebrae (USNM
494403) from the Mancora Formation (Oligocene)
of Peru is tentatively identified as a lampridiform
and its osteology is described.
Though
no synapomorphic characters are observed that
definitively place the specimen within the order
Lampridiformes, features of the anterior portions
of the skull suggest that a lampridiform synapomorphy
may have been present in life. This feature,
combined with numerous similarities of uncertain
polarity found in both the fossil and recognized
lampridiform taxa, suggests that cautious placement
of the specimen within the order Lampridiformes
is warranted.
Other
characters in the fossil, notably the position
of the foramen magnum relative to the exoccipital
condyles, presence of a supraoccipital crest,
and a well-developed first vertebra, exclude
the 5 taeniosomous families of higher lampridiforms
as well as the bathysomous Lamprididae, allowing
for placement of the specimen within the Veliferoidei,
the most basal suborder.
This
specimen is the only fossil lampridiform known
from South America. Given the pelagic habit
of all extant members of the Lampridiformes,
as well as a billfish fossil from the same locality,
it seems likely that the Mancora formation was
deposited in a deep-water, offshore environment.
Project Summary |
Letter
of Gratitude
|
- Gender:
Male.
- Ethnicity/Race:
Native American.
- Institution:
University of Idaho.
- Status:
Sophomore.
- Major:
Biology and Chemistry.
Career
Goals: After
obtaining a Ph.D., achieve a position
in an academic institution conducting
research and courses on coral reef biology.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
|
Michael
C. Holcomb
Project
Advisors: Dr. John Pandolfi and Dr. Ian
Macintyre, Department of Paleobiology.
Project
title: Use of X-radiographs
for coral identification.
Research
Abstract: Recent work has shown the Montastrea
annularis species complex to consist of
at least three extant species. These species
can be distinguished using several techniques,
however, in death assemblages and fossilized
material, identification using conventional
techniques is problematic. Many of the characteristics
commonly used depend upon having whole colonies,
or unabraded corallite surfaces.
Characteristics
measured using X-radiographs were investigated
for their potential to distinguish both modern
and fossil members of the M. annularis
complex. Characteristics showing significant
differences among the species included: maximum
corallite growth angle, band intensity, growth
rate, fan length, corallite angle along the
growth axis, budding angles, and colony curvature.
These characteristics are much less prone to
loss due to taphonomic processes than are many
more conventional ones.
These
results suggest that X-radiographs may serve
as useful tools for separating members of the
M. annularis complex. Considerable geographic
and/or temporal variation was noted as well
as interspecific variation.
Publication:
Holcomb, M., Pandolfi, J.M., Macintyre,
I.G., and Budd, A.F. In prep. Potential use
of X-radiographs to distinguish members of the
Montastraea annularis species complex.
Proposed for publication in Coral Reefs.
Project Summary |
Letter
of Gratitude
|
- Gender:
Female.
- Ethnicity/Race:
White
- Institution:
The University of Michigan
- Status:
Recent graduate
- Major:
Geological Sciences
Career
Goals:
After obtaining a Ph.D., become a professor
or researcher at an academic institution.
Funding:
This student's participation in the summer
2001 Research Training Program was supported
by a grant from the Smithsonian Women's
Committee to provide an opportunity for
international students and graduating
seniors to participate in the program.
|
Holladay,
Laura:
Project
Advisor: Dr. Brian Huber, Department of Paleobiology.
Project
Title: Ontogenetic morphometric
comparison of middle-late Eocene pseudohastigerinid
planktonic foraminifera using X-radiograph image
analysis
Research
Abstract: Middle to late Eocene species
of the planispiral planktonic foraminiferal
genus Pseudohastigerina include P.
micra and P. naguewichensis, which
are widely recognized and easily distinguished
species. Less readily distinguished are Pseudohastigerina
acutimarginata, which resembles P. micra
but has a more pinched peripheral margin, and
a previously unrecognized morphotype that resembles
P. micra in its early ontogeny but becomes
more evolute later in its ontogeny.
To
test whether or not these latter forms should
be synonymized under P. micra, we obtained
high resolution X-radiograph images of specimens
mounted in axial and edge views to characterize
ontogenetic changes in shell and chamber size
and shell coiling. Populations of Pseudohastigerina
were selected from a geographic array of sites
and from several stratigraphic levels within
the middle and upper Eocene. The biometric analyses
demonstrate significant differences in chamber
growth trajectories, chamber coiling, maximum
test size, and roundness of the ultimate chamber
face between populations of P. naguewichensis
and the other three pseudohastigerinid morphotypes.
Populations assigned to P. micra and
P. acutimarginata are statistically indistinguishable
in all coiling and size measurements, and comparison
of ultimate chamber roundness shows a continuous
range of circular to peripherally elongate shapes.
The strongly evolute pseudohastigerinids are
similar to P. micra in all measured features
except final chamber number and maximum test
size.
We
conclude that P. micra and P. acutimarginata
are synonymous and probably represent ecophenotypes,
whereas the evolute pseudohastigerinid forms
are closely related to P. micra but may
represent a new species. Stable isotope data
will also be analyzed in order to infer the
depth ecologies of the various morphotypes.
Publication:
(1):
Holladay, L. and Huber, B. In prep. (to
be submitted to the Journal of Foraminiferal
Research in fall 2001) Ontogenetic morphometric
comparison of middle-late Eocene pseudohastigerinid
planktonic foraminifera using X-radiograph image
analysis.
(2):
Results will be incorporated into the Atlas
of Eocene Foraminifera (Huber, B. et al., in
prep.).
Project Summary |
Letter
of Gratitude
|
- Gender:
Female.
- Ethnicity/Race:
White.
-
Institution:
University of Rhode Island.
- Status:
Junior.
- Major:
Marine Biology.
Career
Goals: After
earning a Ph.D., achieve a career focused
on research in systematics and ecology
of marine invertebrates.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
Update
- December 2002: Abby is in graduate school
at Woods Hole Oceanographic Institution
in the MIT/WHOI Joint Program, working
toward a PhD in Biological Oceanography
under the direction of Ken Halanych
|
Abigail
J. Knee
Project
Advisor: Dr. Kristian Fauchald, Department of
Systematic Biology, Division of Worms.
Project
Title: A cladistic analysis
of the scale worm genus Halosydna.
Research
Abstract: Historically, the annelid class
Polychaeta, the bristleworms, has been wrought
with misclassifications. The taxon has been
presumed polyphyletic. Research focused on monophyly
as a defining characteristic of clades has been
problematic.
Within
the polychaetes, the polynoid family of marine
worms has particularly mystified taxonomists
as this taxon resulted from the systematic removal
of monophyletic groupings of scale worms from
the former family encompassing them all.
The
family Polynoidae consists of scale worms linked
by the presence of scales and do not fit with
the extracted taxa. Using cladistics and the
premise that species represent descent with
modification from a common ancestor, this research
sought to determine the evolutionary relationships
within the polynoid genus Halosydna Kinberg
1855 and in relation to its sister taxa.
The
states of 88 morphological characteristics were
described for eighteen species: eight species
associated either historically or currently
with Halosydna and ten species of closely
related scale worms. Data was entered using
the software DELTA and NDE. With this data,
the computer software program PAUP produced
44 branching trees of relatedness revealing
the most parsimonous paths of speciation based
on the synapomorphies of the species.
Analysis
of some cladograms in TREEVIEW revealed a grouping
of Halosydna species within a monophlyletic
clade, while those species removed to the genus
Halosydnella fall out along various lines
of descent.
Another
notable pattern was the close grouping of Halosydna
brevisetosa and H. leucohyba, proposed
to be synonymous with each other. The resolution
in the ingroup can now be further discussed
so as to lead to evolutionary clarifications.
In the course of the study, two undescribed
species, H. augeneri and H. riojai,
also were discovered in the NMNH worm collection,
previously isolated by M. Pettibone but unpublished.
The descriptions of these two species are to
be submitted in the next year for publication
in the Proceedings of the Biological Society
of Washington.
Publication:
Knee, A.J. and K. Fauchald. In Prep.
A cladistic analysis of the genus Halosydna
(Annelida: Polychaeta: Polynoidae), with a description
of two new species: H. augeneri and H.
riojai. Proceedings of the Biological Society
of Washington.
Project Summary |
Letter
of Gratitude
|
- Gender:
Male.
- Ethnicity/Race:
White.
-
Institution:
North Dakota State University.
- Status:
Junior.
- Major:
Zoology.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
|
Trevor
J. Krabbenhoft
Project
Title: Species-level systematics
of the genus Symphurus (Cynoglossidae:
Pleuconectiformes) of the western Pacific.
Research
Abstract: The new species, described from
82 specimens collected during the Albatross
expeditions around the Philippine Archipelago
in 1909, is characterized by a combination of
characters including fin-ray counts, vertebral
counts, and pigmentation features.
The
new species has a predominant 1-2-2 pattern
of interdigitation of dorsal pterygiophores
and neuralspines and 14 caudal-fin rays.
The
new species is most similar to S. woodmasoni,
but differs drastically in its pigmentation.
Publication:
Krabbenhoft, T. and T. Munroe. In prep.
A new Cynoglossid Flatfish (Symphurus: Cynoglossidae:
Pleuronectiformes) from Deep-waters of the Philippine
Archipelago. Copeia.
Project Summary |
Letter
of Gratitude
|
- Gender:
Female.
- Ethnicity/Race:
White.
-
Institution:
University of New Mexico.
- Status:
Junior.
- Major:
Anthropology and Geology.
Career
Goals: After
obtaining a Ph.D., secure a position at
a university teaching archaeology and
conducting archaeological research.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
Update
- December 2002: Courtney attended the
annual archaeology meetings (67th Annual
Meeting of the Society for American Archaeology,
Denver, 2002) and gave a paper on her
RTP research.
|
Courtney
A. Porreca
Project
Advisor: Dr. J. Daniel
Rogers, Department of Anthropology.
Project
Title: Paste Composition
and Vessel
Function: A Case Study of Caribbean Ceramics.
Research
Abstract: Archaeological ceramics provide
a wealth of information about prehistoric cultures,
including their technology. Prehistoric technology
can also provide information on cultural traditions,
lineages, and interactions, providing a broad
picture of past cultures. Often the composition
of the clay mixture used to make the pottery
reflects technological choices made by the potter.
This
study examines the relationship of this mix
of ingredients and the intended use of the pottery
from a period of almost 2,000 years on the Caribbean
island of Nevis. To examine the clay mixture,
a microscope was used to view cross sections
of cut pottery sherds. The larger particles
were identified and counted, and the form or
shape of the vessel was used to infer its function.
The time period or phase from which the vessels
date was also a variable. The data was then
analyzed to determine the relationship, if any,
between the way the pottery was made and its
intended use.
The
results of this analysis show substantial continuity
in the types and numbers of the inclusions across
the different vessel functions as well as time
periods. The same pattern emerged when the styles
of surface treatments, for example painting
or incising, were compared with the intended
use of the pottery vessel. From this information,
it can be concluded that the clay mixture of
the ceramics from Nevis, as determined by counting
the inclusions, is not directly related to either
the intended function of the vessel or the decorative
style. This is significant because it indicates
a basic technological continuity on Nevis for
almost 2,000 years despite theories of major
cultural interaction due to migrations from
mainland South America.
Future
work that would provide more insight concerning
this issue might include comparisons of the
clay used to make the pottery to that of raw
clay samples from the island, or comparing the
overall Nevis ceramic collection to collections
from other Caribbean islands.
Publication:
Porreca, C. A. and J. D. Rogers. In prep.
Paste Composition and Vessel Function: A Case
Study of Caribbean Ceramics. Journal of American
Archaeology.
Project Summary |
Letter
of Gratitude
|
- Gender:
Female.
- Ethnicity/Race:
White.
-
Institution:
University of Maryland.
- Status:
Non-graduating
Senior.
-
Major:
Anthropology and Art History.
Career
Goals: After
earning a Ph.D., attain a career as a
research scientist at a museum focused
on fieldwork in the Near East, with a
concentration on archaeometric studies.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
Update
- December 2002: Stacy is currently in graduate
school at the University of Pennsylvania
studying Classics.
|
Anastasia
L. Poulos
Project
Advisor: Dr. Melinda Zeder, Curator of Zooarchaeology,
Department of Anthropology.
Project
Title: The Hunting of
Gazella subgutturosa by Early Domesticators
in the Fertile Crescent- A Comparison of Wild
and Domestic Animal Remains in the Archaeological
Record.
Research
Abstract: The method of developing sex-specific
age curves for domestic goat and sheep remains
from archaeological sites has proved valid in
identifying a kill-off profile that is representative
of either domestication or hunting practices
of people 10,000 years ago.
The
application of this technique to the study of
wild, hunted gazelle remains has further reinforced
the potential for this kind of metric study,
which is based on sexual dimorphism and fusion
rates. Modern gazelle specimens were measured
as a means of calibrating the degree of sexual
dimorphism of the gazelle. Sexual dimorphism
proved to be a dominant factor in the size of
various bones. Regional variation was also strongly
prevalent in the specimens; however, the ratio
of male to female remained consistent and replicated
the ratio of sexual dimorphism found in studies
of modern goat and sheep.
This
regional variation was found to be present in
the archaeological record as well. Thousands
of gazelle specimens were analyzed from archaeological
sites throughout the highland and lowland regions
of the Zagros in Iran û Ali Kosh, Asiab,
Sarab, Guran, Palegawra, M'lefaat, and Jarmo.
A comparison of the sex-specific survivorship
curves derived from the archaeological data
of hunted gazelle with that of domestic remains
was a startling contrast. Domestic goats and
sheep replicated a similar pattern of domestication
practice to that of the previously studied site
of domestication, Ganj Dareh, whereas the gazelle
specimens gave strong evidence of a less specific
selection in their hunt. The hunters focused
more haphazardly, although there does seem to
be a trend for the selection of bigger and older
males, interspersed with female and young, which
contrasts with the focused selection of young
males for kill by the domesticators.
Project Summary |
Letter
of Gratitude
|
- Gender:
Female.
- Ethnicity/Race:
Native American.
- Institution:
Haskell Indian Nations University.
- Status:
Junior.
- Major:
Biology with emphasis in Chemistry.
Career
Goals:
After obtaining a Ph.D., become a research
scientist in the field of Ichthyology.
Funding:
Participation in the 2001 summer session
of the Research Training Program was supported
by the National Science Foundation Research
Experience for Undergraduates program,
Award: DBI-9820303.
Update
- December 2002: Yana spent the summer
at OTS in Costa Rica and is now back in
school. The results from her RTP research
were recently submitted for publication.
|
Yana
R. Reid
Project
Advisor: Dr. Ron Heyer, Curator, Department
of Systematic Biology, Vertebrate Zoology, DIvision
of Amphibians and Reptiles.
Project Title: Analysis
of advertisement calls in the genetically diverse
frog taxon currently
known as Leptodactylus fuscus.
Research
Abstract: The focus of this
project was to analyze the advertisement calls
of the Leptodactylus fuscus.
Although
morphologically very similar, previous electrophoretic
analysis demonstrated the likelihood that this
taxon contains more than one species. Using
call analysis with Canary software along with
the statistical application of SYSTAT, the call
variation was quantified throughout the geographic
range of L. fuscus.
Previous
study of genetic differentiation in L. fuscus
demonstrated that there was genetic partitioning
among population units consistent with multiple
species, rather than a single species, characterizing
the unit currently understood as L. fuscus.
Data were analyzed for 32 individual frogs from
24 localities throughout the distributional
range of Leptodactylus fuscus. Data was
taken on 10 calls for each frog (for those recordings
with 10 or more calls). The data taken were
call rate, call duration, carrier frequency,
beginning frequency, ending frequency, frequency
sweep, and temporal characterization of the
waveform. Call rate, call duration, carrier
frequency, ending frequency, and frequency sweep
demonstrated a correlation with temperature
and these parameters were standardized to 25C
for further analysis.
Beginning
frequency did not demonstrate a correlation
with temperature. Multidimensional scaling analysis
of our data indicated that frogs from the same
locality showed the same kind of variation as
frogs from different localities. The advertisement
call data support the single species hypothesis
in Leptodaactylus fuscus. Our study demonstrates
that speciation in frogs is not always accompanied
by differentiation of advertisement calls.
Project Summary
- Gender:
Male.
- Ethnicity/Race:
Foreign, Hispanic.
|
Alexandre
Cunha Ribeiro
Universidade de São Paulo
Ribeirão Preto, Brazil
Richard
P. Vari, Ph.D.
Supervising Scientists
Department of Systematic Biology
Division of Fishes
"It was a great experience
working in my favorite
field, Phylogenetic
Biogeography, in one of
the best museums."
Phylogeny of the genus Oligosarcus Günther:
A preliminary survey
The
genus Oligosarcus comprises 16 species
that occur in most of the major drainages of
the south central portions of South America.
Members of the genus are small to mid-sized
fishes (about 40 to 200 mm) occurring mainly
in streams. With the exception of O. schindleri,
collected from a tributary of Río Charape
which flows into the Rio Madeira of the Amazon
basin, all Oligosarcus species occur
outside the Rio Amazonas basin and no species
of the genus have been collected north of 15º
S (Menezes, 1988). Little ecological information
on Oligosarcus is available although
life history studies of a few species report
that they range from omnivores to fish predators.
Information on intrageneric relationships for
Oligosarcus was effectively nonexistent
and biogeographic hypotheses as a consequence
were not grounded on phylogenetic information.
Data from a series of osteological systems examined
demonstrates that the genus is monophyletic,
provides insight into likely sister groups to
Oligosarcus, and partially resolves the
interrelationships within the genus. The results
of this study indicate that the fragmentation
of the genus Oligosarcus into mostly
allopatric species is congruent with a hypothesis
of speciation associated with somewhat recent
vicariant events as evidenced by the lack of
sympatry between sister groups, a situation
contrary to that in many other fish species
in that region. The sister-group relationship
between O. pintoi and O. planaltinae
suggested by the results is consistent with
the idea that the High-Paraná is a endemic
area. However, the recognition of "lowland
species" and "plateau species"
groups as postulated by Menezes (1988) is not
supported by the phylogeny, since some of the
"plateau species" are more closely
related to a subunit, but not all of the "lowland
species."
This
research was supported by the Alice Eve Kennington
Endowment.
Project Summary |
Letter
of Gratitude
|
- Gender:
Female.
- Ethnicity/Race:
White.
- Institution:
Southampton College, Southampton, NY
- Status:
Graduated in 2001
- Major:
Marine Science with a Biology concentration
Career
Goals:
After obtaining a Ph.D., become a research
scientist at a major university and study
the ecology of estuarine or reef fish.
Funding:
This student's participation in the summer
2001 Research Training Program was supported
by a grant from the Smithsonian Women's
Committee to provide an opportunity for
international students and graduating
seniors to participate in the program.
|
Rowehl,
Julianne
Project
Advisors: Dr. Carole Baldwin, Dr. Lynne Parenti,
Dr. Victor Springer; Division of Fishes
Project
Title: Identification
of Galapagos Entomacrodus (Teleostei:
Blennidae) with comments on relationships within
the Entomacrodus "nigricans"
species group
Research
Abstract: Documenting biodiversity is important
for understanding the complexity of ecosystems,
as a foundation for future conservation decisions,
and for understanding evolution in a historical
context. Comparative morphological studies provide
the basis for recognizing biological diversity.
These studies involve careful comparisons of
the anatomy of organisms, including superficial
features and internal structures such as bones
and cartilage. When a population of animals
belonging to a known genus is discovered in
a geographical area in which the genus has not
been recorded previously, morphological comparisons
with other known species of the genus are needed
to identify the new population. In this study,
fish of the tropical blenny genus Entomacrodus
were collected from the Galapagos Islands in
the eastern Pacific Ocean. This fish has never
been reported from Galapagos. A comparative
morphological study was performed, and the fish
was identified as Entomacrodus chiostictus,
a widespread species in the eastern Pacific.
A study was then performed to examine relationships
of 10 fish species within this genus. The main
differences between the species in the genus
are the coloration patterns, and detailed comparisons
of numerous external and internal features in
this study revealed few other differences. Color
patterns are usually extremely important in
fish because the females and males often recognize
each other on the basis of these patterns. It
has been hypothesized that Entomacrodus
originated in the central Pacific Ocean and
moved eastward to the eastern Pacific and Atlantic.
Results of this study support a Pacific origin
of the genus and suggest a close relationship
