| Current
Projects:
(Click on the blue squares to jump to the project)
Ecology of Injury in Marine Soft sedimentary habitats
Functional Diversity of Subsurface Deposit Feeders
Past Projects & Ongoing
Interests:
Chemoreception
mechanisms in deposit-feeding polychaetes
Potential Population-level effects of pesticide and herbicide toxicity
in Maine Soft-shell Clams (Mya arenaria)
Modeling disturbance: fish
pits
Selected Publications (reprints
available on request)
Sensory Biology
& Ecology:
Lindsay, S.M. 2009. Ecology and biology of chemoreception
in polychaetes. Zoosymposia 2: 339-367 [Review
Paper] (link
to pdf)
Forest, D.L. and S.M. Lindsay. 2008. Observations of serotonin and FMRFamide-like
immunoreactivity in palp sensory structures and the anterior nervous system
of spionid polychaetes. Journal of Morphology 269:544-551
Tsie, M., P.D. Rawson and S.M. Lindsay. 2008. Immunolocalization
of a Gaq protein to the chemosensory organs of Dipolydora quadrilobata
(Polychaeta: Spionidae). Cell & Tissue Research 333:469-480.
Lindsay, S.M. and R.G. Vogt. 2004. Behavioral Responses
of newly hatched zebrafish (Danio rerio) to Amino Acid Chemostimulants.
Chemical Senses 29: 93-100
Lindsay, S.M., T.J. Riordan, Jr., and D. Forest.
2004. Identification and activity-dependent labeling of peripheral sensory
structures of a spionid polychaete. Biological Bulletin 206:65-77.
Riordan, Jr., T.J. and S.M. Lindsay. 2002. Feeding Responses
to particle-bound cues by a deposit-feeding spionid polychaete, Dipolydora
quadrilobata (Jacobi 1883). Journal of Experimental Marine Biology and
Ecology 277:79-95
Lindsay, S.M., T.M. Frank, J. Kent, J. Partridge, and M.I.
Latz. 1999. Spectral sensitivity of vision andbioluminescence in the midwater
shrimp, Sergestes similis. Biol. Bull. 197:348-360
Woodin, S. A., S. M. Lindsay and D. S. Wethey. 1995. Process
specific recruitment cues in marine sedimentary systems. Biological Bulletin
189:49-58.
Ecology of Injury & Regeneration:
Lindsay, S.M. 2010. Frequency of
injury and the ecology of regeneration in marine benthic invertebrates.
Integrative & Comparative Biology 50(4):479-493 [Review Paper]
(link
to article)
Lindsay, S.M., J.L. Jackson, and D.L. Forest. 2008. Morphology
of anterior regeneration in two spionid polychaete species: implications
for feeding efficiency. Invertebrate Biology. 127: 65-79.
Lindsay, S.M. , J.L. Jackson, and S.Q. He. 2007. Anterior
Regeneration in the spionid polychaetes Dipolydora quadrilobata and Pygospio
elegans. Marine Biology 150: 1161-1172 (First published online August
2006)
Lindsay, S. M., D. S. Wethey, and S. A. Woodin.
1996. Modeling browsing predation, infaunal activity, and recruitment
in marine soft-sediment habitats. American Naturalist.148(4):684-699
Lindsay, S. M. and S. A. Woodin. 1995. Tissue loss induces
switching of feeding mode in spionid polychaetes. Marine Ecology Progress
Series 125:159-169
Toxicology:
Lindsay, S.M., J. Chasse, R.A. Butler, R.J. Van Beneden. 2010. Impacts
of stage-specific acute pesticide exposure on predicted population structure
of the soft-shell clam, Mya arenaria. Aquatic Toxicology 98(3):
265-274
Click here for Full C.V.
(all the gory details)
Ecology
of Injury in marine sedimentary habitats: Effect of repeated injury on
infaunal condition and sediment bioturbation
NSF OCE-0825667 (S. Lindsay PI)
The majority of the ocean floor is sedimentary, and
marine sediments play a key role in the flux of nutrients and organic
matter in the ocean. Via their feeding and other activities, infaunal
organisms living in marine sediments influence benthic-pelagic coupling
by processing and redistributing organic matter supplied from the water
column and influencing the supply of nutrients. These activities also
influence recruitment and competitive interactions. Thus, factors that
impact infaunal activity can secondarily impact sediment biogeochemistry
and benthic communities. Non-lethal loss of body tissue is a common event
for marine infauna such as polychaetes, and numerous studies have investigated
the immediate effects of injury on individuals and predicted indirect
effects on ecological interactions in marine soft-sediment habitats.
This study combines field surveys of infaunal injury with laboratory experiments
to examine the effect of repeated injury on a variety of polychaete species.
Because comprehensive measurements relating sediment activity, regeneration
status and nutritional condition of infauna are rare, these experiments
will compare the effect of repeated injury on survival, growth, fecundity,
nutritional condition and sediment disturbance of surface deposit-feeding
and subsurface deposit-feeding polychaetes. Data gathered in the proposed
experiments and surveys will be used to create a more realistic model
of the interacting effects injury has on infaunal populations, sediment
bioturbation, recruitment, and predator populations. Effects of predation
intensity on bioturbation and infaunal populations will be explored. The
proposed research will provide an important new perspective on the ways
infaunal injury impacts benthic community ecology, trophic transfer of
energy, and potentially benthic-pelagic fluxes of nutrients and contaminants.
top
Functional
Diversity of Subsurface Deposit Feeders
NSF OCE0851172 (P. Jumars, PI; S. Lindsay,
co-PI) Pete Jumars and I are both really interested in bioturbation and
deposit-feeding invertebrates. In this collaboration, we are surveying
particle-handling mechanics and the effects of subsurface deposit-feeding
polychaetes on sediments, with an aim to map morphologies
onto function. In particular, I am investigating the size &
muscularization of nuchal organs and other chemosensory structures in
sub-surface deposit-feeding polychaetes to better understand how sensory
structures are deployed while worms burrow, and how the mechanics of burrowing
influences the supply of dissolved (or particle-bound) chemical cues to
worms.
top
Linking
bioturbation and sensory biology: Chemoreception mechanisms in deposit-feeding
polychaetes
NSF OCE0221229 (S. Lindsay, PI; P. Rawson, co-PI)
Marine soft-sediment benthic habitats typically feature
large numbers of deposit-feeding invertebrates such as polychaetes, bivalves,
gastropods, crustaceans, holothurians, and hemichordates. By feeding on
sediments, defecating, tube-building and burrowing, deposit-feeders exert
profound effects on the ecology, biology, geology, and chemistry of their
habitats. Evidence suggests that their feeding and sediment-disturbing
activities are modulated in part by chemoreception. In this project, we
investigated the process of chemoreception and how it coordinates deposit
feeding in spionid polychaete worms. We described the ultrastructure and
innervation of putative sensory structures on spionid feeding palps using
electron and confocal microscopy. After describing the effect of particle-bound
chemical cues on feeding behavior of the spionid Dipolydora quadrilobata,
we showed that these same cues activated sensory cells on the feeding
palps in activity-dependent cell-labeling studies. Molecular biological
results suggest that the chemoreception signal transduction pathway in
D. quadrilobata involves G-protein coupled receptors, and we found g-protein
alpha subunit immunoreactivity localized in nuchal organs and sensory
cilia on the feeding palps. Three graduate students, three undergraduate
students and three high school interns were mentored on this project.
top
Potential Population-level
effects of pesticide and herbicide toxicity in Maine Soft-shell Clams
(Mya arenaria)
Maine Sea Grant (R. VanBeneden PI, S. Lindsay co-PI)
Pollution by agricultural pesticide and herbicide can be detrimental to
sediment-dwelling marine invertebrates such as copepods and polychaete
worms. Although many ecotoxicological experiments focus on individual
responses to contaminants, pollutants can affect all levels of biological
organization, from cells to ecosystems. Like many infaunal species, soft-shell
clams are broadcast spawners; eggs and sperm are shed into the water column,
and fertilized eggs develop into free-swimming feeding larvae. The larvae
develop through several stages before settling and metamorphosing into
juveniles on the mudflat. In Maine, the progression from spawn to set
can take 4 – 6 weeks and juveniles grow for 1-2 years before reaching
adult size (Newell and Hidu, 1986). Thus, clams may be exposed to pesticides
and herbicides from different routes (waterborne vs. sediment associated)
depending on stage. Given recent results suggesting that such toxins can
reduce adult reproduction, in this project we combined laboratory experiments
and computer modeling to address the question of how common agricultural
pesticides and herbicides might impact the population dynamics of soft-shell
clams.
Modeling disturbance:
fish pits
With Pete Jumars
As an extension of Pete's interest in the effects of biota on acoustic
backscatter, and my interest in the effects of sediment disturbance on
infaunal communitites, we are using MATLAB to model the disturbance created
by fish feeding on the sediment surface in order to predict what effects
such activity might have on acoustic back-scatter.
top |
Many infauna lose body parts exposed above the sediment
surface to browsing predators. © S. Lindsay
|
Our confocal image of the regenerating brain in a spionid polychaete
made the cover of Invertebrate Biology! (2008)
|
Dipolydora quadrilobata 6 days after ablation
of anterior 5 segments (SEM).
© S. Lindsay
|
Histological staining can reveal past injury in
some polychaetes up to a month after they lost segments.
© S. Lindsay
|
G protein subunit immunoreactivity (black) localizes
to palps and nuchal organs of this spionid polychaete (confocal).
© M. Tsie & S. Lindsay.
|
Are there population level consequences of pesticide
and herbicide impacts on clam larvae and juveniles?
|
A theoretical fish bite.
|
|
