Marine Biological Laboratory Research Articles

How the Early Voltage Clamp Studies of José del Castillo Inform “Modern” Neuroscience

The description of ionic currents that flow across the membrane of the squid giant axon during an action potential sparked an interest in determining whether there were similar currents in vertebrates. The preparation of choice was the node of Ranvier in single myelinated fibers in frog. José del Castillo spent 3 years on the United States mainland from 1956 to 1959. During that time, he collaborated with Jerome Y. Lettvin and John W. Moore. I discuss how these individuals met one another and some of their scientific discoveries using the voltage clamp to study squid giant axons and frog nodes. Much of this work was conducted at the Marine Biological Laboratory in Woods Hole, MA, and I attempt to convey a sense of the unique scientific “melting pot” that existed at the Marine Biological Laboratory and the broader effect that del Castillo had on “modern” neuroscience.

An MBoC Favorite: A guide to simple and informative binding assays

This MBoC Technical Perspective (Pollard, 2010) was sorely needed. The author had been grousing about this for some time and conveying it in various quarters. One occasion was the Woods Hole Marine Biological Laboratory (MBL) Physiology Course. He had given a typically fine lecture, during which he had stunned the students by asking whether they knew the equilibrium association constants for any of the protein–protein complexes being studied in the course. The silence in the MBL Lille auditorium was deafening. This unease continued to work on the author and was manifest later in the didactic underpinnings of a distinctive textbook he coauthored with Bill Earnshaw. His MBoC Technical Perspective was a wake-up call about shabby versus proper binding assays, supportively emphasizing that the concepts and methodology are in fact not so daunting, with the added imperative that the investigator should care. Elegantly written, this was a class act.

About the Cover.

Next article FreeAbout the CoverPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreCoverOn the cover is a 72-hour-old larva of the pencil sea urchin Cidaris blakei. Adults of this species live in the Bahamas at depths from 500 to 700 meters. On pages 105 to 117, Kathleen Bennett and her co-authors describe the development of this sea urchin in the first report of a deep-sea urchin reared all the way through metamorphosis.C. blakei is a member of the cidaroids, the most ancient and primitive branch of sea urchins. Cidaroid sea urchins first appeared in the Permian (more than 255 million years ago), and modern forms have strong morphological resemblances to their fossil ancestors. About 130 extant species of cidaroids inhabit shallow, shelf, and deep-sea habitats at tropical, temperate, and Antarctic latitudes, compared to the more than 720 species of Euechinoids, their sister group. The latter includes such common genera as Strongylocentrotus (the familiar green and purple urchins) and Arbacia.Only a few studies have detailed the development of any cidaroid. C. blakei is of particular interest not only because it is a cidaroid but also because it inhabits the deep sea where its larvae must develop in the absence of light and where conventional foods for larvae are sparse. For this study, the authors collected adults with a submersible, spawned them in the laboratory, and cultured the embryos and larvae through metamorphosis. They found that the feeding larvae of C. blakei closely resemble those of other cidaroids, but take much longer (up to 4 months) to reach metamorphosis. Although the larvae can develop on a diet of unicellular algae, they cannot tolerate temperatures in the euphotic zone where this food occurs. It thus seems plausible that their diet consists of larger phytoplankton cells or seston particles sinking to the depths where the larvae reside.Credits: Cover photo, Kathleen C. Bennett, Oregon Institute of Marine Biology, University of Oregon; cover deign, Beth Liles, Marine Biological Laboratory. Next article DetailsFiguresReferencesCited by The Biological Bulletin Volume 222, Number 2April 2012 Published in association with the Marine Biological Laboratory Article DOIhttps://doi.org/10.1086/BBLv222n2cover Views: 202 © 2012 by Marine Biological Laboratory. All rights reserved.PDF download Crossref reports no articles citing this article.

Eric Davidson

Eric Davidson

Keragaman makrozoobenthos di perairan Kuala Gigieng Kabupaten Aceh Besar

Abstract. The objective of present study was to study the diversity of macrozoobenthos in Kuala Gigieng estuary, Aceh Besar. The study was conducted in June 2011. The random sampling method was used to determine the area and sampling points based on tidal activities. Samples were taken with the Eckmann grab, then identified at Marine Biological Laboratory of Marine Science Department. The results showed that there were three class of macrozoobenhos (Malacostraca, Gastropoda, and bivalves) within 12 species of makrozoobenthos occured in Kuala Gigieng. The Shannon-Wienner diversity index (H') at high tide, mean sea level, and low tide were 1.26, 1.446, and 1.892, respectively, and it was categorized as low level. Keywords. Diversity, Makcrozoobenthos, Gigieng estuary

Erratum: The Biological Bulletin, Volume 222, Number 1, Table 1, p. 50.

Previous article FreeErratum The Biological Bulletin, Volume 222, Number 1, Table 1, p. 50Original articleVisual Wavelength Discrimination by the Loggerhead Turtle, Caretta carettaPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreThe Biological Bulletin, Volume 222, Number 1, Table 1, p. 50Table 1 of the article by Morgan Young, Michael Salmon, and Richard Forward, “Visual wavelength discrimination by the loggerhead turtle, Caretta caretta,” contains an error in the last column. The value 10 should be substituted for the value 1 in the row for the no. 2.5 filter. The corrected table is reproduced below in its entirety.Table 1. The number of hatchlings that crawled into the illuminated arm (+), the dark arm (−), or that failed to crawl (0) during the phototaxis trialsLog stimulus intensityBlueGreenYellow+−/0+−/0+−/0No filter12014192 1.0102123132 1.5232123180 2.018*820616***4 2.516923**61510 3.0111416987 3.557101087 P < 0.04P < 0.001P = 0.006Data are shown beginning with the brightest light (no ND filter present; blue, 1.63 × 1014 photons/cm2/s, green, 2.87 × 1013 photons/cm2/s and yellow, 5.03 × 1013 photons/cm2/s), and then as intensity was decreased by inserting combinations of neutral density filters differing in optical density. The phototaxis threshold (bold) is the minimum intensity that evoked significant attraction to the light stimulus (at P ≤ 0.05 by a binomial test). Previous article DetailsFiguresReferencesCited by The Biological Bulletin Volume 222, Number 2April 2012 Published in association with the Marine Biological Laboratory Article DOIhttps://doi.org/10.1086/BBLv222n2pviii © 2012 The University of ChicagoPDF download Crossref reports no articles citing this article.Related articlesVisual Wavelength Discrimination by the Loggerhead Turtle, Caretta caretta29 Sep 2016The Biological Bulletin

Guest Editorial: It’s Time To e-Volve: Taking Responsibility for Science Communication in a Digital Age

Guest Editorial: It’s Time To e-Volve: Taking Responsibility for Science Communication in a Digital Age

Cell biology of micro-organisms and the evolution of the eukaryotic cell

A comparative or evolutionary approach is a powerful addition to the cell biologist's armory. It can provide context for observations in more classical model systems; it can elucidate the forces shaping the morphology, organization, and complexity of the cell; and it can identify new phenomena that may eventually be recognized as crucial to how cells work. Over the past 15 years, genome sequencing has facilitated comparative work in microbial eukaryotes, while advances in cellular imaging technologies have opened up prokaryotes as models for the study of cell biology. At the 2011 ASCB meeting, the Minisymposium entitled “Cell Biology of Micro-organisms and the Evolution of the Eukaryotic Cell” highlighted mechanisms that underpin the evolution of complexity in cells, described new and unexpected microbial cellular phenomena, and reported the development of technologies that will allow us to explore new avenues in the study of microbial cells. The session began with the theme of eukaryotic cell evolution and emergent complexity. Using a combination of comparative genomics and structural modeling Fred Mast (University of Alberta) described an evolutionary model for how multiple organellar cargoes compete for transport by myosin V (Mast et al., 2011 ). Aaron Turkewitz (University of Chicago) extended this theme by discussing evidence that evolutionary diversification of the Rab family of small GTPases scales with increasing complexity of cellular membrane trafficking and compartmentalization (Bright et al., 2010 ). Mark Slabodnick (University of California, San Francisco) concluded the session's presentations on unicellular eukaroytes with his progress report on the development of new molecular tools to study cell division and regeneration in the giant ciliate, Stentor. The second half of the minisymposium centered on the biology of bacterial cells, and began with Alex Valm (Marine Biological Laboratory–Woods Hole), who described an exciting new fluorescence imaging method. Combinatorial labeling and spectral imaging fluorescence in situ hybridization (CLASI-FISH) uses dozens of combinations of fluorescent probes that provide an unprecedented look at the spatial composition of complex bacterial cell communities (Valm et al., 2011 ). Joel Kralj (Harvard University) reported the development of a voltage-sensitive fluorescent protein known as the proteorhodopsin optical proton sensor (PROPS). Expression of PROPS in Escherichia coli revealed unexpected, high-frequency electrical spiking (Kralj et al., 2011 ) that coincided with efflux of a small fluorophore from the cell. The results of these studies suggest that some bacterial cell efflux processes may be electrically regulated. Finally, Sean Crosson (University of Chicago) described recent data on molecular and genetic determinants of cell cycle control and cell differentiation in the bacterium Caulobacter crescentus. These studies have defined how the broadly conserved regulatory molecules guanosine tetraphosphate and inorganic polyphosphate link nutrient limitation to cell differentiation at the G1–S cell cycle transition in a bacterial cell (Boutte et al., 2012 ). All of these talks make us rethink our ideas about “normal” cell biology and awakened us to the “endless forms most beautiful and most wonderful” into which the cell has evolved.

Abstracts of the 17th International Symposium on Bioluminescence and Chemiluminescence ‐ (ISBC 2012)

WARNING : The light-emitting molecular structures responsible for the chemiluminescence and fluorescence phenomena are not necessarily the same!

Development of Xenopus resource centers: the National Xenopus Resource and the European Xenopus Resource Center.

Xenopus is an essential vertebrate model system for biomedical research that has contributed to important discoveries in many disciplines, including cell biology, molecular biology, physiology, developmental biology, and neurobiology. However, unlike other model systems no central repository/stock center for Xenopus had been established until recently. Similar to mouse, zebrafish, and fly communities, which have established stock centers, Xenopus researchers need to maintain and distribute rapidly growing numbers of inbred, mutant, and transgenic frog strains, along with DNA and protein resources, and individual laboratories struggle to accomplish this efficiently. In the last 5 years, two resource centers were founded to address this need: the European Xenopus Resource Center (EXRC) at the University of Portsmouth in England, and the National Xenopus Resource (NXR) at the Marine Biological Laboratory in Woods Hole, MA. These two centers work together to provide resources and support to the Xenopus research community. The EXRC and NXR serve as stock centers and acquire, produce, maintain and distribute mutant, inbred and transgenic Xenopus laevis and Xenopus tropicalis lines. Independently, the EXRC is a repository for Xenopus cDNAs, fosmids, and antibodies; it also provides oocytes and wild-type frogs within the United Kingdom. The NXR will complement these services by providing research training and promoting intellectual interchange through hosting mini-courses and workshops and offering space for researchers to perform short-term projects at the Marine Biological Laboratory. Together the EXRC and NXR will enable researchers to improve productivity by providing resources and expertise to all levels, from graduate students to experienced PIs. These two centers will also enable investigators that use other animal systems to take advantage of Xenopus' unique experimental features to complement their studies.

Women in Science

Breaking through Spiral Ceiling . Laura L. Mays Hoopes . 2010. Lulu Publishing. (ISBN 9780557923205). 163 pages. Paperback. $14.00. The primary focus of Laura Hoopes's Breaking through Spiral Ceiling is narration of her struggle as a woman in science in 20th century, before, as she says, men were ready for women in science. Hoopes's career as in biochemical genetics takes her to Goucher College, Marine Biological Laboratories, Yale University, and Occidental College. Hoopes narrates her progression from discovery of her passion for cell biology, biochemistry, and the thrill of refining of her approach to scientific questions, Ph.D. qualifying exams and graduate research, to her role as a researcher, professor, and mentor in her own right. Hoopes also explores tension between roles of research …

Nrf2b, Novel Zebrafish Paralog of Oxidant-responsive Transcription Factor NF-E2-related Factor 2 (NRF2)

NF-E2-related factor 2 (NRF2; also called NFE2L2) and related NRF family members regulate antioxidant defenses by activating gene expression via antioxidant response elements (AREs), but their roles in embryonic development are not well understood. We report here that zebrafish (Danio rerio), an important developmental model species, possesses six nrf genes, including duplicated nrf1 and nrf2 genes. We cloned a novel zebrafish nrf2 paralog, nrf2b. The predicted Nrf2b protein sequence shares several domains with the original Nrf2 (now Nrf2a) but lacks the Neh4 transactivation domain. Zebrafish-human comparisons demonstrate conserved synteny involving nrf2 and hox genes, indicating that nrf2a and nrf2b are co-orthologs of human NRF2. nrf2a and nrf2b displayed distinct patterns of expression during embryonic development; nrf2b was more highly expressed at all stages. Embryos in which Nrf2a expression had been knocked down with morpholino oligonucleotides were more sensitive to tert-butylhydroperoxide but not tert-butylhydroquinone, whereas knockdown of Nrf2b did not affect sensitivity of embryos to either chemical. Gene expression profiling by microarray identified a specific role for Nrf2b as a negative regulator of several genes, including p53, cyclin G1, and heme oxygenase 1, in embryos. Nrf2a and Nrf2b exhibited different mechanisms of cross-talk with the Ahr2 signaling pathway. Together, these results demonstrate distinct roles for nrf2a and nrf2b, consistent with subfunction partitioning, and identify a novel negative regulatory role for Nrf2b during development. The identification of zebrafish nrf2 co-orthologs will facilitate new understanding of the multiple roles of NRF2 in protecting vertebrate embryos from oxidative damage.

Neural control of dynamic structural coloration in squid iridophores.

Event Abstract Back to Event Neural control of dynamic structural coloration in squid iridophores. Trevor J. Wardill1*, Paloma T. Gonzalez Bellido1*, Robyn Crook2 and Roger T. Hanlon1 1 Marine Biological Laboratory, Marine Resources Center, United States 2 University of Texas Medical School, Department of Integrative Biology and Pharmacology, United States Fast dynamic control of skin coloration is rare in the animal kingdom, whether it be pigmentary or structural. Iridescent structural coloration results when nanoscale structures disrupt incident light and selectively reflect specific colors. Unlike animals with fixed iridescent coloration (e.g. butterflies), squid iridophores produce dynamically tunable structural coloration, as exogenous application of the acetylcholine (ACh) changes the color and brightness output. However, previous efforts to stimulate iridophores neurally or to identify the source of the ACh were unsuccessful, leaving researchers to question the activation mechanism. We developed a novel neurophysiological preparation in the fin of Doryteuthis pealeii (aka. Loligo pealeii) and demonstrated, for the first time, that electrical stimulation of neurons in the skin shifts the color spectrum (>145 nm) and increases the luminosity (>245 %) of innervated iridophores. By forward filling the stimulated nerves, we traced extensive nerve branching within the convoluted iridophore platelets. We show the dynamic color shift is significantly faster (17 s) than the luminosity increase (32 s) revealing two distinct mechanisms. Responses from a structurally altered preparation indicate that the reflectin protein condensation mechanism explains luminosity change, while an undiscovered mechanism causes the fast color shift. Acknowledgements TJW and PTGB share first authorship. We thank Hanlon lab members for discussion and in particular Lydia Mathger for help with spectrometry and advice. We thank MBL equipment resources and Zeiss Microscopes for assistance with equipment. We thank MBL Central Microscopy for imaging resources and MBL Aquatic Resources Division for supplying squid. We are very grateful for funding from ONR Basic Research Challenge grant # N00014-10-1-0989, DARPA grant W911NF-10-1-0113 and AFOSR grant FA9950090346. Keywords: Acetylcholine, Electrophysiology, Iridescence, Neural Stimulation, Whole-mount microscopy Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster (but consider for Participant Symposium) Topic: Neuromodulation Citation: Wardill TJ, Gonzalez Bellido PT, Crook R and Hanlon RT (2012). Neural control of dynamic structural coloration in squid iridophores.. Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00264 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 30 Apr 2012; Published Online: 07 Jul 2012. * Correspondence: Dr. Trevor J Wardill, Marine Biological Laboratory, Marine Resources Center, Woods Hole, MA, 02543, United States, twardill@umn.edu Dr. Paloma T Gonzalez Bellido, Marine Biological Laboratory, Marine Resources Center, Woods Hole, MA, 02543, United States, paloma@mbl.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Trevor J Wardill Paloma T Gonzalez Bellido Robyn Crook Roger T Hanlon Google Trevor J Wardill Paloma T Gonzalez Bellido Robyn Crook Roger T Hanlon Google Scholar Trevor J Wardill Paloma T Gonzalez Bellido Robyn Crook Roger T Hanlon PubMed Trevor J Wardill Paloma T Gonzalez Bellido Robyn Crook Roger T Hanlon Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Bully for Science! The FASEB Centennial (1912–2012)

Bully for Science! The FASEB Centennial (1912–2012)

Evidence for a rhodopsin-retinochrome photosensitive system in chromatophores of the squid, Loligo pealeii

Event Abstract Back to Event Evidence for a rhodopsin-retinochrome photosensitive system in chromatophores of the squid, Loligo pealeii Alexandra Kingston1*, George Bell2, Alan M. Kuzirian2, Roger T. Hanlon2 and Thomas W. Cronin1 1 University of Maryland Baltimore County, Biological Sciences, United States 2 Marine Biological Laboratory, Marine Resources Center, United States Cephalopods, including squid, cuttlefish, and octopus, are hypothesized to have extraocular photoreceptors located in their skin. These putative photoreceptors are thought to detect light using an opsin-based photoreception system. In photoreceptors of the retina, an opsin protein is bound to a retinal chromophore to form a functional photopigment, and retinochrome acts as a photoisomerase, recycling the chromophore. The presence of opsin and retinochrome in close proximity suggests the presence of a functional photoreceptor. My work focuses on detecting opsin and retinochrome in putative extraocular photoreceptors in the skin of the longfin squid, Loligo pealeii. We searched for opsin and retinochrome in the skin and retinas of L. pealeii using RT-PCR. Opsin was detected in the retina, ventral mantle, ventral fin surface, 1st arm, 2nd arm, 3rd arm, 4th arm, tentacle and muscle tissue of L. pealeii. Retinochrome was detected in all these locations as well as the dorsal mantle and dorsal fin surface. Identical opsin and retinochrome transcripts were also detected in dissociated chromatophores from several locations. Future work will include in situ hybridization and immunohistochemistry to determine in what cells opsin and retinochrome transcripts and proteins are expressed. Keywords: chromatophore, retinochrome, Rhodopsin Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster (but consider for participant symposium and student poster award) Topic: Sensory: Vision Citation: Kingston A, Bell G, Kuzirian AM, Hanlon RT and Cronin TW (2012). Evidence for a rhodopsin-retinochrome photosensitive system in chromatophores of the squid, Loligo pealeii. Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00169 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Apr 2012; Published Online: 07 Jul 2012. * Correspondence: Ms. Alexandra Kingston, University of Maryland Baltimore County, Biological Sciences, Baltimore, MD, 21250, United States, acnahm@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Alexandra Kingston George Bell Alan M Kuzirian Roger T Hanlon Thomas W Cronin Google Alexandra Kingston George Bell Alan M Kuzirian Roger T Hanlon Thomas W Cronin Google Scholar Alexandra Kingston George Bell Alan M Kuzirian Roger T Hanlon Thomas W Cronin PubMed Alexandra Kingston George Bell Alan M Kuzirian Roger T Hanlon Thomas W Cronin Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Adaptation in phasic auditory units of the frog midbrain is sensitive to changes in stimulus frequency and ear of input

Event Abstract Back to Event Adaptation in phasic auditory units of the frog midbrain is sensitive to changes in stimulus frequency and ear of input Abhilash Ponnath1, Kim Hoke2 and Hamilton Farris1* 1 Louisiana St. University Health Sciences Center, Neuroscience, United States 2 Colorado State University, Biology, United States Neural adaptation, a reduction in response to a constant or maintained stimulus, is an important mechanism for detecting stimulus change. Contributing to stimulus change detection is the fact that neural adaptation is often stimulus specific: adaptation to a particular stimulus reduces excitability to only a subset of stimuli, while the ability to respond to other stimuli is unaffected. Phasic cells (e.g., responding to stimulus onset), with their fast adaptation, are considered good candidates for detecting the most rapid changes in natural auditory scenes, as they adapt quickly to the initial presentation of a stimulus and do not require adaptation buildup from many repeated stimulus presentations. Our study uses in vivo, single unit recordings to show that the fast and complete adaptation of phasic auditory units in the frog torus semicircularis is specific to stimulus frequency and ear of input. In response to an instantaneous frequency step in a 200 ms tone, 28% of cells exhibit frequency specific adaptation (FSA) based on relative frequency change (delta-f = +/-16%). FSA is not limited to frequency steps, however, as adaptation is also overcome during continuous frequency modulated stimuli. When temporal gaps in tones produce frequency transients, FSA cells outperform non-FSA cells in gap detection. When gaps in noise produce only temporal cues, however, gap detection is identical in the two cell classes. The results suggest that adaptation is separated for peripheral (e.g., frequency) channels, which we tested directly using dichotic stimuli. In 45% of binaural phasic units, adaptation was ear specific: adaptation to stimulation of one ear does not affect responses to stimulation of the other ear. Thus, adaptation exhibits specificity during processing of frequency and lateralization at the level of the midbrain. This mechanism could be employed to detect stimulus change within and between acoustic sources in rapidly changing complex acoustic environments. Acknowledgements KLH and HEF were supported in part by a Grass Faculty Fellowship at the Marine Biological Laboratory, Woods Hole, MA (2009). AP and HEF were supported by NIH grant P20RR016816 (to N. Bazan). Keywords: adaptation, auditory scene, chorus, critical band Conference: Tenth International Congress of Neuroethology, College Park. Maryland USA, United States, 5 Aug - 10 Aug, 2012. Presentation Type: Poster Presentation (see alternatives below as well) Topic: Sensory: Audition Citation: Ponnath A, Hoke K and Farris H (2012). Adaptation in phasic auditory units of the frog midbrain is sensitive to changes in stimulus frequency and ear of input. Conference Abstract: Tenth International Congress of Neuroethology. doi: 10.3389/conf.fnbeh.2012.27.00157 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 27 Apr 2012; Published Online: 07 Jul 2012. * Correspondence: Dr. Hamilton Farris, Louisiana St. University Health Sciences Center, Neuroscience, New Orleans, Louisiana, 70112, United States, hfarri@lsuhsc.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Abhilash Ponnath Kim Hoke Hamilton Farris Google Abhilash Ponnath Kim Hoke Hamilton Farris Google Scholar Abhilash Ponnath Kim Hoke Hamilton Farris PubMed Abhilash Ponnath Kim Hoke Hamilton Farris Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Monitoring of a Posidonia oceanica bed (Punta Manara, Eastern Ligurian Sea, Italy) and the associated molluscs twenty years after: What's new?

This research project by the Marine Biology Laboratory at Turin University determined the degree of conservation and measured the size of the Posidonia oceanica bed in the eastern Ligurian Sea off Punta Manara in 1985–1986, a bed that had also been examined in 1973. This project assessed the structure, dynamics, and organization of the foliar stratum malacofauna in relation to the most important space–time variables, the bathymetric gradients, and the seasons. In 2006 the laboratory investigated this bed with methods like the previous ones in order to evaluate the effect of anthropogenic disturbances and to assess any changes in the P. oceanica and mollusc-community dynamics. Our overall project has spanned many years, something unique in P. oceanica studies. Our structural analysis of the meadow found (i) a reduction in shoot density in all the bed's regions, particularly in the shallow and intermediate belts; (ii) a progressive reduction of the lower limit (now considered erosive–regressive). We sampled the foliar stratum molluscs using hand-towed nets, the means we used to collect semi-quantitative data. In 2006, there were 40% fewer specimens and 31.5% more species than in 1985–1986. The core-stock (sensu Russo) has remained the same over the years in terms of both the presence and the abundance of species (8 dominant species belonging to Cerithidae and Rissoidae). As in 1985–1986, Bittium latreillii is the dominant species, whose juveniles exhibited similar settlement dynamics on the foliar strata and whose samples had comparable peaks in reproduction and abundance. The multivariate approach was applied to both the 1985–1986 and the 2006 data set. The present results confirm those obtained through the Detrended Correspondence Analysis (DCA) in 1985–1986. Namely, time (the period or the season) is the main factor of variability, the one that influences the malacological assemblages the most. The composition of the stocks depends closely on the sampling period (ANOSIM, R=0.532, P<0.001) and hence is linked to the biological cycle of the seagrass. The development of P. oceanica affects the malacological assemblages and regulates them quantitatively, something most evident in the reproductive and settlement cycles of the two dominant families, Cerithidae and Rissoidae. Thus the spatial variations (the variations in depths or bathymetric gradient) play a major role in determining the species of the stocks, while the temporal variations – the changes in seasons – play a major role in determining the total number of molluscs.

Progress of marine biodiversity studies in China seas

Efforts have been made by scientists studying on the taxonomy, biogeography and biodiversity in China seas since 1950, the establishment of Qingdao Marine Biological Laboratory, Chinese Academy of Sciences (CAS). Over 1,000 papers and 200 volumes of monographs have been published, of which more than 47 volumes are Fauna Sinica ― Invertebrata (27 volumes on marine biota), 11 volumes of Fauna Sinica ― Vertebrata are on fishes, and 8 volumes are Flora Algarum Marinarum Sinicarum. Results of studies on biodiversity in whole China seas were summarized in Marine Species and Their Distributions in China’s Seas’ (1994) and Checklist of Marine Biota of China Seas (2008). In the latter volume, new taxonomic results up to 2007 were added, and a total of 22,629 marine species were recorded, with an increase of 5,118 species compared with those reported in 1994. So far, the biodiversity of China seas is high. The results of “Shelf Environment and Bio-resources Survey 1997–2000” and those of “Endangered Species Assessment 第 6期 刘瑞玉: 中国海物种多样性研究进展 615 Project” (2000–2004) published in China Species Red List vols.1, 3, 2A, 2B (2004, 2005 and 2009) revealed that under the impacts of global climate change and anthropogenic activities, the biodiversity and bio-resources have seriously declined, the number of endangered species increased, and some major populations collapsed. China joined the World Marine Biodiversity Project “Census of Marine Life” (CoML) in 2004. In the project “Census of Marine Zooplankton”, ecosystem dynamics and biodiversity characteristics had been investigated; and in a survey cruise from Arctic to Antarctic through Equator, 2000 zooplankton samples were taken by R/V “Science I” of Institute of Oceanology, CAS, and 260 DNA barcoding data have been obtained. For the CoML “NRIC: Synthesis Program”, the China Collection Report entitled “Status of marine biodiversity study in China seas” had been drafted and submitted to PLoS ONE for publication, the progress of China’s marine biodiversity and biogeography studies has been reviewed by the present author. To strengthen the conservation of biodiversity and endangered species, 33+21 National Marine Nature Reserves and 7 National Marine Parks have been established up to date. Problems in marine biodiversity study and conservation in China seas are discussed and the following suggestions are put forward: (1) To strengthen the collection of materials (specimens) for marine biodiversity study, a biodiversity background value survey and deep sea collection cruises should be carried out to discover new species and reveal the past, present, and to predict the future trends of major species and biological communities; (2) Carrying on biodiversity monitoring survey in various habitats around the country, to understand the processes and mechanisms of global climate change and human activities impacting biodiversity; (3) Strengthening basic research on change in marine biodiversity, particular the assessment and conservation of biodiversity and endangered species for sustainable development; (4) Minimizing the disparity between the study and conservation of marine and terrestrial (including freshwater) biodiversities, and effective management; and (5) Training young scientists, particularly taxonomists to study different biotic groups systematically.

Anomalous Infrared Taxis of an Aquatic Animal, the Giant Jellyfish Nemopilema nomurai (Scyphozoa, Rhizostomeae)

Remote sensing of thermal radiation (infrared wavelengths) has been reported only in some terrestrial animals and is known to have significant physiological and ecological meaning. In aquatic animals, however, it has not even been discussed because water almost completely absorbs infrared (IR) wavelengths, and such sensitivity has been regarded as useless in aquatic environments. Here we report, for the first time, an anomalous behavior—swimming toward an IR-radiating source—in an aquatic animal, the giant jellyfish, Nemopilema nomurai. Experiments were performed with laboratory-reared juvenile medusae of Nemopilema in a small experimental chamber. In all 52 trials, the majority (average: 78.3%; variation: 63.3%– 94.3%) of the medusae gathered on the IR-irradiated half of the chamber. Near-IR (850/940 nm) and visible light neither attracted the medusae nor induced taxis. A series of results indicated that the juveniles of Nemopilema tended to flock toward a mass of warmer water. Although the exact physiological and ecological meaning of this behavior is uncertain, it might be possible to consider infrared taxis as one of the behaviors in marine ecosystems. It may thus be useful to re-examine the swarming behavior reported in some jellyfish species from the viewpoint of IR taxis. Infrared (IR) sensitivity is known to be mediated by the so-called pit organs, which enable crotaline and boid snakes to apprehend homeothermic prey (1–7) and vampire bats to detect IR radiation from blood-rich locations (8, 9). Moreover, similar mechanisms have been reported in some insects such as fine debris species of beetle (10–13), bloodsucking bugs (14), and some butterflies (15, 16). In aquatic animals, however, little is known about the IR sensitivity. This is the first report to describe an anomalous IR-tactic behavior in the giant jellyfish, Nemopilema nomurai, living in an aquatic environment. Nemopilema nomurai Kishinouye 1922 is one of the largest scyphozoan jellyfish, measuring 1–2 m in diameter and weighing 100–200 kg. Massive blooms of this species have occurred almost annually since 2002, severely affecting coastal fisheries in the Sea of Japan. The life cycle of N. nomurai has been well established by us and our coworkers (17, 18), so the juvenile medusae are easily available. We thus used laboratory-reared juveniles (extended bell diameter, 8–15 mm) to examine the IR sensitivity of N. nomurai. The experimental chamber (width 30 cm, length 24 cm, height 16 cm) used to test IR sensitivity was made from transparent acryl resin plate (5 mm thick). It was filled with seawater to a depth of 3.5 cm and 20 to 35 juvenile individuals were added. The distribution of the medusae in the chamber was monitored by photographing them from above with a photographic strobe every 30 or 60 min. The IR wavelengths were obtained from a tungsten-filament lamp (40 W) by passing the light through a long-pass filter (50% cut-on at 990 nm; LIO-990, Asahi Spectra Co. Ltd.). The tungsten-filament lamp was fixed in a lightproof aluminum housing with a window, where the long-pass filter was mounted. All possible heat sources, except for the IR-wavelength source, were excluded from around the experimental chamber. Near-IR wavelengths, 940 and 850 nm, were obtained from two types of 1.2-W LEDs, LB12WP01 and LC12-WP01 (Ebisu Electronics Co. Ltd.), reReceived 1 August 2011; accepted 20 October 2011. * To whom correspondence should be addressed. E-mail: ohtsu@ life.shimane-u.ac.jp Reference: Biol. Bull. 221: 243–247. (December 2011) © 2011 Marine Biological Laboratory

Measuring and modeling roots, the rhizosphere, and microbial processes belowground

Measuring and modeling roots, the rhizosphere, and microbial processes belowground