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Jones, Kate. "Monitoring, Assessment, and Management of the Green Sea Urchin (Strongylocentrotus droebachiensis) Fishery in Maine". Fogler Library, University of Maine, 2006. http://www.library.umaine.edu/theses/pdf/JonesKX2006.pdf.
Pełny tekst źródłaKling, Ashley Lindsey. "Effects of Formulated Feeds and Saccharina Latissima on Growth, Gonadal-Somatic Index, and Gonad Color in Grow-Out Stage Green Sea Urchins, Strongylocentrotus droebachiensis, in Land-Based Echiniculture". Fogler Library, University of Maine, 2009. http://www.library.umaine.edu/theses/pdf/KlingAL2009.pdf.
Pełny tekst źródłaLau, Chi Chung Dickey. "Population variability and impact of sea urchin Anthocidaris crassispina in Hong Kong". HKBU Institutional Repository, 2011. https://repository.hkbu.edu.hk/etd_ra/1298.
Pełny tekst źródłaHeyland, Andreas. "Thyroid hormone-like function in echinoids a modular signaling system coopted for larval development and critical for life history evolution /". Connect to this title online, 2004. http://purl.fcla.edu/fcla/etd/UFE0004542.
Pełny tekst źródłaSweijd, Neville Anthony. "The digestive mechanisms of an intertidal grazer, the sea urchin Parechinus angulosus". Thesis, Rhodes University, 1991. http://hdl.handle.net/10962/d1005346.
Pełny tekst źródłaChiu, Sein-tuck. "Aspects of the ecology of Anthocidaris crassispina (echinodermata: echinoidea) in Hong Kong /". [Hong Kong : University of Hong Kong], 1987. http://sunzi.lib.hku.hk/hkuto/record.jsp?B1233571X.
Pełny tekst źródłaFarquhar, Michael Robert. "Interspecific interactions of the sea urchin Parechinus angulosus and the effect of variations in microhabitat availability". Thesis, Rhodes University, 1995. http://hdl.handle.net/10962/d1005406.
Pełny tekst źródłaTauchman, Eric Gary. "Effects of ultraviolet radiation on developing variegated sea urchins, lytechinus variegatus". [Pensacola, Fla.] : University of West Florida, 2008. http://purl.fcla.edu/fcla/etd/WFE0000142.
Pełny tekst źródłaOlquín, Irma. "Speciation in marine systems : the case study of the sea urchin Arbacia incisa (Agassiz 1863) /". For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.
Pełny tekst źródłaIncludes bibliographical references (leaves 65-72). Also available via the World Wide Web. (Restricted to UC campuses)
Cowart, Dominique Alexandria. "Salinity sensitivity of embryos of the Antarctic sea urchin, Sterechinus neumayeri". Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 47 p, 2008. http://proquest.umi.com/pqdweb?did=1597631011&sid=37&Fmt=2&clientId=8331&RQT=309&VName=PQD.
Pełny tekst źródłaPisut, Daniel P. (Daniel Peter). "The distance chemosensory behavior of the sea urchin Lytechinus variegatus". Thesis, Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/5129.
Pełny tekst źródłaHusby, Kjell Runar. "Development of a Grading Machine for Sea Urchins". Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for produktutvikling og materialer, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22711.
Pełny tekst źródłaFilander, Zoleka. "Systematics and biodiversity of South African sea urchins". Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/12925.
Pełny tekst źródłaThe South African Echinoidea (Echinodermata) were last reviewed by Clark & Courtman Stock (1976) and numerous unidentified specimens and records have accumulated since that time, plus there have been many taxonomic changes within the group. Therefore this study, which forms the first of its kind in 37 years, aims to update knowledge on the diversity and distribution patterns of South African echinoids and to provide a user-friendly, well-illustrated guide to the group. Dry and wet specimens, particularly those within the extensive collections of the Iziko South African Museum, were morphologically examined and identified, and the associated data were added to a database. Other data considered in this study include; historic data from the South African Museum and University of Cape Town catalogues, imagery data from the EchinoMapVM open-online database, trawl by-catch data from the Department of Forestry and Fisheries, and data from published literature. These resulted in 19 new records for the region, of which 84.2% were Indo-Pacific, 5.3% introduced, and the remaining 10.5% non-endemic, raise the total number of known species to 71. All species were photographically illustrated and a field guide is presented which included synonomy and previous literature for each species, one of more photographic illustrations, a distribution map, description and notes on global distribution. In terms of biogeography the regional echinoid fauna comprises 26.8 % endemics, 1.4 % introduced, and 71.8 % non-endemics; across 14 orders and 29 families. As expected, species richness pattern increased from west to east coast. However , the east coast displayed the lowest number of records; as compared to the South coast, which had the highest. Endemism peaked on the south coast and the west and east coast both supported the same level of endemics. The only introduced species, Tetrapygus niger, was from the west coast region. In terms of depth; species richness was highest in<500m and lowest in>500m.This maybe a result of the deep-seas (>500m) being severely under-sampled. The lack of full-time taxonomists and lack of expertise to review this group, may have contributed to the high number of new records.
Lawson, T. N. "Physical mapping of an early sea urchin gene battery from Parenchinus angulosus". Master's thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/17701.
Pełny tekst źródłaThe aim of this project was to characterise an early histone gene battery isolated from Parenchinus angulosus. An early histone gene battery (named H27) which was believed to have been isolated from Parenchinus angulosus, appeared by restriction enzyme mapping and partial sequencing to be identical to H22, an early histone gene battery isolated from Psammechinus miliaris. (This latter gene was obtained from M. Birnstiel.) This was further confirmed by electron microscopy, and proved to be a convenient testing ground for the electron microscopic techniques of denaturation mapping and heteroduplex anlysis. Another gene battery (named SU1) isolated fromParenchinus angulosus, was then characterised using the techniques developed whilst studying H27. The restriction enzyme map of this clone is different to that of H22, indicating that differences do indeed exist between these two early histone gene batteries. SU1 also showed the expected order of the five histone genes, as determined by hybridization against the coding regions of H22. The denaturation map of SU1 showed AT rich spacer regions and GC rich coding regions. Heteroduplex analysis indicated that the spacer regions between the Hl and H2A, the H2A and H3, and the H3 and the H2B gene coding areas are essentially nonhomologous. The H4 structural gene and corresponding spacer regions were not included in this analysis. Because it is known that all the five histones are coded for on the same strand of DNA in H22, and that each of the genes is transcribed in the same direction, it follows that, the same holds for, at least, the Hl, H2A, H3 and H2B genes of SU1.
Bennett, Kathleen 1977. "The Complete Development of the Deep-Sea Cidaroid Urchin Cidaris blakei (Agassiz, 1878) With an Emphasis on the Hyaline Layer". Thesis, University of Oregon, 2009. http://hdl.handle.net/1794/10169.
Pełny tekst źródłaLiving echinoids comprise two major sister clades, the Euechinoidea and the Cidaroidea. Cidaroids first appeared during the lower Permian (~255 mya) and are considered to represent the primitive form of all other living echinoids. The present study of Cidaris blakei, a deep-sea planktotrophic cidaroid urchin, provides a description of development from fertilization through early juvenile stages and is the first report of a deep-sea organism reared through metamorphosis. Cidaris blakei resembles other cidaroids in its lack of a cohesive hyaline layer, the absence of an amniotic invagination for juvenile rudiment formation, and the presence of a single spine morphotype at metamorphosis. Cidaris blakei differs from other cidaroids in the presence of an apical tuft, the extent of fenestration of postoral skeletal rods, the shape of juvenile spines and an extended (14 day) lecithotrophic stage prior to development of a complete gut. This study includes my co-authored materials.
Adviser: Alan Shanks
Muller, Cornelius Marthinus. "The phylogeographic population structure of the Cape sea urchin, Parechinus angulosus". Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/6899.
Pełny tekst źródłaENGLISH ABSTRACT: South Africa's coastline is in the region of 3650kms and encompasses many different and dynamic marine environments. To enhance our current understanding of the population structure and gene flow patterns of intertidal zone marine species in this region, this study sets out to investigate the phylogeographic population structure of the Cape sea urchin, Parechinus angulosus, using mitochondrial and nuclear DNA sequence data collected in 2007 and 2008. Individuals were sampled from 18 geographic locations between southern Namibia and Durban, covering nearly the full extent of the species range. Sequence data were obtained from a 790bp region of the COI mtDNA gene (n=510) and a 182bp region of the nDNA SpREJ9 gene (n=145), respectively. The mtDNA data revealed 283 polymorphic sites (36%) defining 195 haplotypes, of which 160 were unique and 35 shared among individuals. Haplotype diversity (h) was found to be high both overall (h=0.95) and for individual localities (h=0.75-0.98), with nucleotide diversity (π) being low overall (π=0.013) as well as for individual localities (π=0.0033-0.0254). AMOVA revealed significant population structure among sampling sites in the Namaqua Province biogeographical region, as well as between three of the four respective coastal biogeographic provinces/regions. Gene flow was bi-directional among sampling sites in the south coast Agulhas and East Coast Province biogeographical regions, while gene flow in the Namaqua Province appears to be dominated by northwards movement. BAPS identified a significant break in the Cape Point region, which was also reflected in the gene flow patterns and parsimony networks. This broadly corresponds to previously identified biogeographic regions as well as genetic breaks for other marine species found along this coast. Fu's Fs statistics showed strong signal(s) of population expansion for individual sampling localities as well as for the data set as a whole, while MDIV estimated a time since expansion ranging from 7733-4759 years ago. The nDNA data revealed 54 variable sites (29.7%), defining 72 alleles of which 50 were unique and 22 shared among individuals. Many of the alleles (69.4%) were restricted to single sampling sites, with Betty's Bay on the south coast being the most diverse from a genetic viewpoint. Allelic diversity was high overall (h=0.86) while nucleotide diversity was low (π=0.025). No nuclear sub-group structure was identified by BAPS, although the parsimony network revealed shallow genetic structure between the Namaqua and Agulhas Provinces, with significant pairwise ФST values also recovered between their individual coastal localities. This points to at least one major barrier to gene flow for Parechinus angulosus along the South African coast, namely Cape Point. Several additional, smaller hindrances to gene flow along the coast were also identified, most of which are congruent with findings from studies on both other and sea urchin species. As a standalone study this research elucidated many aspects regarding the phylogeography of the Cape sea urchin, P. angulosus. However, it is when viewed in the broader context of invertebrate phylogeography along the southern African coastline that this research will provide its most critical insight.
AFRIKAANSE OPSOMMING: Geen opsomming
Egana, Ana Luisa. "Analysis of the centrosome during sea urchin oogenesis and the characterization of sphedgehog expression and function during sea urchin embryogenesis /". Thesis, Connect to Dissertations & Theses @ Tufts University, 2000.
Znajdź pełny tekst źródłaAdviser: Susan G. Ernst. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 91-118). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
Carboni, Stefano. "Research and development of hatchery techniques to optimise juvenile production of the edible sea urchin, Paracentrotus lividus". Thesis, University of Stirling, 2013. http://hdl.handle.net/1893/13178.
Pełny tekst źródłaYounglao, Deborah. "Spawning, aggregation and recruitment in the black sea urchin Diadema antillarum". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=64064.
Pełny tekst źródłaSwanson, Rebecca School of Biological Earth & Environmental Sciences UNSW. "Histamine ??? a naturally occurring settlement cue for larvae of the Australian sea urchin Holopneustes purpurascens". Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2006. http://handle.unsw.edu.au/1959.4/27240.
Pełny tekst źródłaVrable, David Joseph. "A recombinant GST-EMBP440 fusion protein from sea urchin embryos that has myosin binding capabilities /". Connect to online version, 1997. http://hdl.handle.net/1989/3741.
Pełny tekst źródłaSzulgit, Greg Karl. "Mechanical investigations of the mutable collagenous tissues of the echinoderms, Eucidaris tribuloides, Cucumaria frondosa, and Parastichopus parvimensis /". Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1998. http://wwwlib.umi.com/cr/ucsd/fullcit?p9823697.
Pełny tekst źródłaCunningham, John Alexander. "The evolution of developmental strategy in cretaceous spatangoid sea urchins". Thesis, University of Liverpool, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511069.
Pełny tekst źródłaGong, Zhiyuan. "Regulation of tubulin gene expression in sea urchin embryos". Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74267.
Pełny tekst źródłaConlon, Ronald A. "Underexpression of paternal genes in sea urchin interspecies hybrid embryos". Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63341.
Pełny tekst źródłaPelikan, Kellie C. "The Effects of Petroleum Pollutants on Sea Urchins Reproduction and Development". NSUWorks, 2015. http://nsuworks.nova.edu/occ_stuetd/401.
Pełny tekst źródłaBaron-Taltre, Benjamin. "The Rise and Fall of the Maine Sea Urchin Industry: A Failure of Management and Institutions?" Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/Baron-TaltreBX2005.pdf.
Pełny tekst źródłaDuerr, Heike Edith. "Molecular characterisation of neuropeptides in echinoderms". Thesis, Royal Holloway, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314294.
Pełny tekst źródłaSardhalia, Vaskar. "Calcium carbonate-naphthoquinone hybrid pigments inspired by biomineral coloration in sea urchins". Electronic Thesis or Diss., Sorbonne université, 2023. https://accesdistant.sorbonne-universite.fr/login?url=https://theses-intra.sorbonne-universite.fr/2023SORUS644.pdf.
Pełny tekst źródłaThe vibrant colors seen in adult sea urchin biominerals, ranging from purple to green, are attributed to the presence of polyhydroxylated naphthoquinone molecules (PHNQs). These PHNQs become integrated into calcite, likely during the crystal growth, which occurs through amorphous calcium carbonate (ACC) precursors. The mineral formation in sea urchins is accompanied by color changes depending upon the stage of mineralization. Spinochrome A, for example, exhibits a red color when extracted from the purple spines of Paracentrotus lividus in acidic conditions, indicating a potential link between pH and color variations, as observed in CaCO3 formation. To delve deeper into color variations and the impact of naphthoquinones on ACC crystallization, we performed CaCO3 precipitation in the presence of PHNQs (extracted from sea urchin spines) and commercially available natural naphthoquinones (naphthazarin, lawsone, and juglone). We monitored pH levels throughout the formation of colored ACC and its crystallization into calcite. Various analytical techniques, including DSC/TGA, XPS, PDF analysis, UV-Vis, STEM-EELS, ss-NMR spectroscopy, and HR-XRD, were employed to characterize the properties of the amorphous and crystalline hybrid pigments. Our results reveal that different pigments can create a spectrum of colored calcite. For instance, naphthazarin, transitioning from red at acidic pH, turns medium blue before ACC precipitation, culminating in lavender blue calcite due to successive O-H deprotonation/protonation. The effect of increasing naphthazarin concentration on ACC's stability against crystallization in solution and air followed different trends without affecting the local structure of the ACC. Quantification of naphthazarin associated with ACC and calcite revealed that only a tiny fraction of naphthazarin associated with ACC gets incorporated within the calcite in the form of non-homogeneous nano inclusions; the rest was adsorbed on the surface with strong chemical or physical forces. Furthermore, spinochrome A yields purple calcite, while spinochrome B and E produce yellowish calcite. HR-XRD analysis indicates that spinochrome B and E induce more significant distortions in calcite lattice than spinochrome A. Moreover, spinochrome A increased the stability of the intermediate polymorph, thus modifying the crystallization pathway. The combination of minimal atomic structural effects and intense coloring suggests a preference for incorporating spinochrome A in the purple spines of P. lividus. The PHNQs extracted from sea urchin spines and hybrid pigment were tested for textile dyeing, showcasing promising results in the case of biogenic PHNQs and ACC-based hybrid pigments
Miner, Benjamin G. "Evolution of phenotypic plasticity insights from echinoid larvae /". Connect to this title online, 2003. http://purl.fcla.edu/fcla/etd/UFE0001450.
Pełny tekst źródłaMontpetit, Isabelle. "Localization and characterization of an ectodermal protein of sea urchin embryos". Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59519.
Pełny tekst źródłaRiedemann, Johann. "Functional analysis and recombinant expression of a sea urchin G-string binding factor". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52277.
Pełny tekst źródłaThesis (MSc)--Stellenbosch University, 2001.
ENGLISH ABSTRACT: The sea urchin G-string binding factor 1 (suGF1) has previously been shown to bind with high affinity and selectivity to stretches of contiguous deoxyguanosine residues, a DNA motif found in the upstream regions of many unrelated genes from several organisms. It has been proposed that suGF1 plays a role in transcriptional regulation. Homopurine.homopyrimidine stretches have been shown to form unusual DNA structures, in vitro. To investigate the potential of the suGF1 binding site to form unusual structures under certain conditions, synthetic oligodeoxyribonucleotides containing the suGF1 poly(dG).(dC) binding site were subjected to circular dichroism (CD) analyses. The CD results indicate that the suGF1 binding site forms a mixture of unusual DNA structures, as deduced by comparison with the spectra obtained for B-DNA, triplex and quadruplex conformations. These results are consistent with the hypothesis that suGF1 specifically recognises G-strings that exhibit unusual structures. Exhaustive database searches showed that suGF1 has no significant homology with any previously identified proteins or cDNAs from any species. Given the relevance of mammalian models to medical science, and since no sea urchin cell lines are currently available, the identification of a mammalian functional homologue would facilitate determination of the in vivo function of such a potentially important, putative, novel DNAbinding protein in mammalian cell lines. In this study sequence analysis tools were used to identify hORFX, a putative human functional homologue of suGF1. Similarities in the domain organisation of the two proteins, prompted an investigation into the DNA-binding properties of hORFX, as well as a more detailed structure prediction analysis, with a view to determining whether hORFX is a functional homologue of suGF1. hORFX was successfully expressed in vitro, but lacked the ability to specifically bind G-strings. Theoretical predictions suggest that suGF1 has a DNA-binding domain belonging to a different family to that predicted for hORFX, consistent with differences in their respective DNA-binding specificities. suGF1 and hORFX were predicted to have helix-turn-helix and helix-loop-helix DNA-binding domains, respectively. Taken together the results do not support the hypothesis that hORFX is a suGF1 homologue. To date, no direct evidence for the in vivo function of suGF1 has been obtained. With a view to performing transactivation assays in the future, the expression of suGF1 in yeast was investigated in this project. An suGF1 expression construct was engineered and transformed into a protease-deficient yeast strain. Nuclear extracts were prepared and subjected to SOS-PAGE and electrophoretic mobility shift assays (EMSAs). suGF1 was shown to be successfully expressed in yeast cells and exhibited similar G-string-binding properties to that of native and in vitro transcribed and translated (IVT) suGF1. The suGF1 eDNA was also subjected to in si/ico expression, which together with the SDSPAGE results of yeast nuclear extracts and IVT suGF1, indicated that the protein might be expressed as multiple truncated products, due to the utilisation of multiple AUG translation start sites. These in vitro results are crucial for the ultimate outcome and correct interpretation of future transactivation experiments and lay the foundation for further investigation into the possible role of suGF1 in transcriptional regulation.
AFRIKAANSE OPSOMMING: In die verlede is bewys dat die seepampoentjie G-string-bindende faktor (suGF1) hoë affiniteit en spesifisiteit vir aaneenlopende volgordes van deoksiguanosien residue besit. Hierdie DNA motief kom algemeen voor in die stroom-op gebiede van verskeie gene in verskillende organismes. Daar is 'n veronderstelling dat suGF1 betrokke is by die regulering van geenuitdrukking. Vroeër is bewys dat homopurien.homopirimidien-ryke areas die vermoë besit om in vitro ongewone DNA-strukture te vorm. Die potentiaal van die suGF1-bindingsetel om ongewone DNA-strukture te vorm is gevolglik deur sirkulêre dikroïsme (SD) analise ondersoek. Vergelyking van die spektra vir B-DNA-, tripleks- en kwadrupleks-strukture met dié van die suGF1-bindingsetel, toon duidelik dat laasgenoemde 'n mengsel van ongewone DNA konformasies, onder die spesifieke eksperimentele omstandigehede, aanneem. Deeglike inspeksie van die beskikbare geen- en proteïendatabasisse vir alle spesies het aangetoon dat suGF1 geen merkbare kDNA- of proteïenhomoloë besit nie. As gevolg van die belang van soogdiermodelsisteme in die mediese wetenskappe, asook die onbeskikbaarheid van seepampoentjie-sellyne, is 'n soektog na 'n funktionele suGF1 homoloog in soogdiere geloods. Die ontdekking van só 'n homoloog sal dit moontlik maak om die rol van hierdie potensiaal belangrike en unieke DNA-bindingsproteïen te ondersoek. Tydens hierdie soektog is spesiale analise-programme gebruik en 'n potensiële menshomoloog van suGF1, hORFX, is geïdentifiseer. Die mees prominente ooreenkoms tussen die twee proteïene is die soortgelyke rangskikking van funksionele motiewe. Gevolglik is die DNA-bindings eienskappe van die hORFX-proteïen ondersoek, insluitende 'n detaileerde struktuur-funksie-voorspelling ten einde vas te stel of dit wél 'n homoloog van suGF1 is. hORFX is suksesvol uitgedruk in vitro, maar besit nie die vermoë om dieselfde G-string waaraan suGF1 spesifiek bind te herken nie. Teoretiese analise het voorspel dat suGF1 en hORFX aan verskillende DNA-bindings proteïen-families behoort, aangesien suGF1 'n heliks-draai-heliks en hORFX 'n heliks-lus-heliks motief bevat. Hierdie inligting, tesame met die eksperimentele resultate, dui aan dat hORFX nie 'n homoloog van suGF1 is nie. Tot op hede is daar niks bekend aangaande suGF1 se funksie in vivo nie. Met die oog op transaktiveringseksperimente in die toekoms, is die ekspressie van suGF1 in gisselle tydens hierdie navorsingsprojek ondersoek. 'n suGF1 ekspressievektor is berei en gebruik om 'n protease-negatiewe gissellyn te transformeer. Kernekstrakte is ondersoek deur SDS-PAGE en elektroforetiese mobiliteitsessais. Daar is gevind dat suGF1 suksesvol uitgedruk is in die gisselle. Die rekombinante suGF1 besit G-volgorde bindingsaktiwiteite soortgelyk aan dié van suGF1 in kernekstrakte van seepampoentjies, asook in vitro getranskribeerde-en getransleerde suGF1. Die kDNA vir suGF1 is ook in silico uitgedruk. Tesame met die SDS-PAGE-resultate het laasgenoemde aangetoon dat die suGF1-kDNA veelvuldige AUG-kodons bevat vir die inisiasie van proteïentranslasie. Dit lei moontlik tot die translasie van 'n reeks proteïenprodukte wat verkort is aan die N-terminale kant, afgesien van die volledige suGF1-proteïen. Die in vitro resultate in geheel is essensieel vir die toekomstige uitvoering en interpretasie van transaktiveringseksperimente. Hierdie projek lê gevolglik die fondasie vir 'n verdere ondersoek na die rol van suGF1 in die regulering van geenuitdrukking.
Cole, Russell Gavin. "Distributional relationships among subtidal algae, sea urchins and reef fish in northeastern New Zealand". Thesis, University of Auckland, 1993. http://hdl.handle.net/2292/1912.
Pełny tekst źródłaHarianto, Januar. "Physiological response of adult and juvenile sea urchins (Heliocidaris erythrogramma) to warming and acidification". Thesis, The University of Sydney, 2018. http://hdl.handle.net/2123/20420.
Pełny tekst źródłaTaylor, Anna M. "Effects of dietary carbohydrate on weight gain and gonad production in juvenile sea urchins, Lytechinus variegatus". Birmingham, Ala. : University of Alabama at Birmingham, 2006. http://www.mhsl.uab.edu/dt/2006m/taylor.pdf.
Pełny tekst źródłaYamamori, Luna. "Ecology and adaptative evolution of gastropods and cirripeds symbiotic with sea urchins in marine rocky reefs". Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263723.
Pełny tekst źródła新制・課程博士
博士(人間・環境学)
甲第23262号
人博第977号
京都大学大学院人間・環境学研究科相関環境学専攻
(主査)教授 加藤 眞, 教授 市岡 孝朗, 准教授 西川 完途
学位規則第4条第1項該当
Doctor of Human and Environmental Studies
Kyoto University
DGAM
Chiu, Sein-tuck, i 趙善德. "Aspects of the ecology of Anthocidaris crassispina (echinodermata: echinoidea) in Hong Kong". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1987. http://hub.hku.hk/bib/B31230805.
Pełny tekst źródłaFabrèges, Dimitri. "Phenotypic Variations In Animal Morphogenesis : Sea Urchin Twins And Cloned Rabbits". Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLS010/document.
Pełny tekst źródłaVariability is an intrinsic characteristic of biological systems, essential for evolution and embryogenesis.Considered as noise for centuries, it is only recently that the stochasticity of biological processes has began to be systematically explored.The present thesis addresses the following questions: What is a normal development?What is the extent and role of variability in developmental robustness and resilience?We tackle these issues in rabbit (Oryctolagus cuniculus) and sea urchin (Paracentrotus lividus and Sphaerechinus granularis).We also aimed to quantify determinism and stochasticity of developmental variability by means of sea urchin twins and cloned rabbits.Variations in cell behaviors were investigated through reconstruction of cell lineage from 3D+time imaging.We showed that sea urchin twins can follow three different developmental paths never observed in normal embryo, before converging to normal looking blastula.Moreover, comparisons between and within pairs of twins revealed that phenotype and survival depend on individual history alone.Our quantitative observation of twin pairs raises question opening a future line of research: are twins robust or resilient?Rabbit preimplantation development was explored with five digital specimens (three wild-types and two clones) from the 32-cell stage to hatching.We showed that inner and outer asymmetric divisions regulate the variation of inner cell number and may control inner cell mass size.In addition, the variation of inner cell number in clones is higher than outer cells which seems to be directly correlated to their cell death ratio.Our current hypothesis is that the potential to lead to viable clones requires plasticity of donor's epigenetic state.This work is expected to ground concepts and methods for a quantitative exploration and further multilevel modeling of morphogenetic processes
Vanderklift, Mathew Arie. "Interactions between sea urchins and macroalgae in south-western Australia : testing general predictions in a local context". University of Western Australia. School of Plant Biology, 2002. http://theses.library.uwa.edu.au/adt-WU2004.0086.
Pełny tekst źródłaHereu, Fina Bernat. "Role of trophic interactions between fishes, sea urchins and algae in the northwestern Mediterranean rocky infralittoral, The". Doctoral thesis, Universitat de Barcelona, 2007. http://hdl.handle.net/10803/1443.
Pełny tekst źródłaOwing to the existence of previous investigations, my work, strictly speaking, does not break any new ground, since the subject matter has already been well studied in other oceans (see Castilla 2000 for a revision). Paradoxically, the Mediterranean, them cradle of the natural sciences (Aristotle, 350 BC) and home to the invention of scuba diving by Gagnan and Cousteau in 1944, has generally not been witness to any of the most important advances in experimental benthic science. Whilst not wanting to question the universality of discoveries regarding benthic communities made in other waters, it can surely not be an excessive precaution to attempt to understand the way regional peculiarities - the Mediterranean is a very singular sea in many ways (Margalef 1985) - affect general principals.
One highly significant way in which benthic experiments in the Mediterranean are playing a part in current debate is the role that marine reserves or protected marine areas (PMAs) can be expected to play as management tools in ecosystems adversely affected by human action. In this sense, my work shares a characteristic with many others: the use of marine reserves as experimental sites that can be compared with nearby unprotected zones in order to try and judge their worth.
As a final reflection on the main object of study in my thesis it is worth remarking that the system under study relates on a trophic level macroscopic algae - the main primary producers in the phyto-benthos - to their herbivores, which in the coastal Mediterranean benthos are essentially a sea urchin (Paracentrotus lividus), a fish, the salema (Sarpa salpa), and a guild of omnivorous fish that include optional grazers of algae and predators on sea urchins. My study investigated the interactions taking place between all the actors in this complex community and not just the interactions occurring between a certain group of species, although inevitably, given its central position, the sea urchin Paracentrotus lividus has been the focal point of our efforts. As a means of simplifying, throughout this paper I often refer to the "triangle" 'algae-sea urchins-fish', which is described in more detail in Annex 1.
I feel that my work has two main applications. Aside from any knowledge gained from the experimental study of the interactions within a complex community under natural conditions, our results have, firstly, a clear role to play in the management of coastal areas and biological conservation in general. It is known that high densities of sea urchins can cause a regression and a loss of diversity in algal communities (that can be compared to the effects of desertification on the biodiversity of forest ecosystems).
Studying experimentally the mechanisms that regulate these interactions is a way of searching for valid management criteria. Secondly, we looked at the relevance of the role played by changes of anthropic origin such as eutrophication or overfishing in the proliferation of sea urchins and the regression of algal communities.
Dins el ventall d'especialitats en que s'acostuma a dividir l'ecologia, aquesta tesi s'enquadra en l'anomenada "ecologia de comunitats" (Diamond i Case 1986). Amb més precisió, el meu treball ha estat dedicat a investigar el grau en que les relacions tròfiques entre els organismes que formen una xarxa tròfica arriben a governar l'estructura i dinàmica de la comunitat que formen. L'aproximació es experimental i tot el treball s'ha realitzat al camp, basat en el que hom anomena "experiments naturals" amb les seves virtuts i inconvenients. L'ecosistema triat ha estat el bentos marí litoral, i en concret les comunitats de l'infralitoral rocós. Es tracta d'un marc de treball favorable, ja que aquest escenari ha produït algunes de les contribucions més importants a l'ecologia de comunitats, sobretot en el que fa al desenvolupament de la seva vessant experimental (revisat per Castilla 2000).
A causa d'aquests treballs precedents, una part dels objectius del meu treball no és estrictament novedosa, ja que han estat molt estudiats en altres mars (veure Castilla 2000 per a una revisió). Paradoxalment tractant-se del mar que ha estat el bressol de les ciències naturals (Aristòtil, cap el 350 a.C.) i de la invenció de l'escafandre autònom per Gagnan i Cousteau el 1944, la Mediterrània ha quedat en gran mesura fora de l'àrea on han tingut lloc els avenços de l'ecologia bentònica experimental. Tot i que confíem en l'universalitat de les descobertes més sòlides de l'ecologia de comunitats bentòniques, mai serà una precaució excessiva per als ecòlegs copsar la forma en que les particularitats regionals (la Mediterrània es un mar en molts sentits singular; Margalef 1985) modelen aquests principis generals.
A més, almenys en una part sí que les experiències d'ecologia bentònica mediterrànies participen de la més disputada actualitat, i és en el paper que hom pot esperar que realitzin les Reserves Marines o Àrees Marines Protegides (MPA's) com eines de gestió racional d'uns ecosistemes massa castigats per l'acció humana. En aquest sentit el meu treball comparteix amb molts altres que es realitzen actualment el tret d'utilitzar les Reserves Marines com un dels tractaments experimentals estudiats i, per comparació amb el que succeeix a les zones properes no protegides, tracta d'esbrinar els seus efectes.
Per acabar de focalitzar el tema objecte de la meva tesi només cal afegir que el sistema estudiat és el que relaciona tròficament les algues macroscòpiques, com principals productors primaris del fito-bentos, amb els seus herbívors, que al bentos litoral mediterràni es poden simbolitzar en una espècie de garota de mar ("Paracentrotus lividus") i un peix ("Sarpa salpa"), i amb el gremi de peixos omnívors entre els que es compten opcionals pasturadors d'algues i depredadors de les garotes herbívores. L'estudi aborda les interaccions entre tots els elements d'una comunitat complexa, i no només d'algunes espècies selectes, encara que, pel seu paper central, la garota "Paracentrotus lividus" ha concentrat més esforços que la resta. Al llarg de la memòria i per simplificar, parlarem sovint d'aquest "triangle" algues-garotes-peixos, que es descriu amb més detalls en l'Annex 1.
Crec que l'interès d'aquest treball pot ser doble. Més enllà del coneixement que pot aportar a l'Ecologia de comunitats l'estudi experimental de les interaccions d'una comunitat complexa en condicions naturals, els resultats tenen un clar interès aplicat per a la gestió dels litorals i per a la biologia de la conservació. És sabut que altes densitats de garotes poden provocar la regressió de les comunitats algals i una forta pèrdua de diversitat (que pot ser comparada als efectes de la desertització sobre la biodiversitat dels ecosistemes forestals). Estudiant experimentalment els mecanismes que regulen aquestes interaccions busquem aportar criteris vàlids per a la gestió. Un tema d'especial interès ha estat esbrinar quin paper han pogut jugar canvis d'origen antròpic, com els derivats de l'eutrofització o de la sobre-pesca, en la proliferació de les garotes i la regressió de les comunitats algals.
Soars, Natalie Anne. "Habitat soundscapes and sound production by tropical and temperate sea urchins and the swimming behaviour of their larvae". Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/13923.
Pełny tekst źródłaPoorbagher, Hadi, i n/a. "Life-history ecology of two New Zealand echinoderms with planktotrophic larvae". University of Otago. Department of Marine Science, 2008. http://adt.otago.ac.nz./public/adt-NZDU20081029.160011.
Pełny tekst źródłaMörk, Erik. "Macroalgal community dynamics on coral reefs : Implications for management". Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-48281.
Pełny tekst źródłaAt the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Accepted. Paper 4: Manuscript. Paper 5: Manuscript.
Day, Elizabeth. "Ecological interactions between abalone (Haliotis midae) juveniles and sea urchins (Parechinus angulosus), off the south-west coast of South Africa". Doctoral thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/9690.
Pełny tekst źródłaField surveys were carried out in the kelp beds of the shallow subtidal off the south western Cape of South Africa, which confirmed the existence of a strong positive relationship between the urchins Parechinus angulosus and juveniles of the abalone Haliotis midae. Both species occupied primarily hard substrates, showing preferences for encrusting corallines. Of the juvenile abalone sampled, > 98% were found beneath sea urchins. All small (3-10 mm shell length) and medium sized (11-20 mm shell length) abalone juveniles occurred under urchins, whether on flat or vertical reef, or in crevices. A small proportion (approximately 10%) of large juveniles (21-35 mm shell length) were not found under urchins, and in these instances all occupied crevices instead. Subsequent surveys also revealed a positive, but weaker, association between abalone recruits (<3 mm shell length) and urchins - an unexpected result, given that abalone recruits are cryptic against the encrusting coralline substrate that they occupy preferentially. Thus camouflaged, they were assumed to gain little additional benefit from sheltering beneath urchins. Selectivity indices showed that, amongst different morphological categories of encrusting corallines, recruits showed preferences for strongly-textured corallines, such as the so-called "knobbly" and "paint" textures. Lower densities of recruits per unit substrate area were recorded on the smoother "velvet" corallines. However, almost all (80%) of recruits were found on velvet corallines occurred under urchins, as opposed to 28 and % of recruits on paint and knobbly corallines respectively.
Farina, Simone. "Scale-dependent factors modulate sea urchin predation in macrophyte communities". Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/325691.
Pełny tekst źródłaEn esta tesis se examina cómo la estructura de macrófitos marinos pueden mediar las interacciones tróficas entre depredadores y herbívoros, y cómo estos procesos varían en función de la escala espacial. Se comienza explorando las variaciones de la actividad de depredación en relación a la complejidad estructural de la pradera de Posidonia oceánica. En el primer capítulo se examina cómo la cobertura foliar y el nivel de enterramiento de los rizomas influye en la intensidad de la depredación de erizos. Los resultados demuestran que la estructura de la pradera juega un papel fundamental a la hora de determinar las tasas de depredación de estos sistemas mediante el control de la disponibilidad de refugio para los erizos. En el segundo capítulo se profundiza en algunas de las cuestiones abiertas en el primer capítulo comparando las tasas de depredación en un gradiente de complejidad estructural de diferentes praderas de macrófitos. Para poder generalizar los resultados, se comparan las tendencias encontradas entre tres diferentes bioregiones —Caribe, Mediterráneo occidental y Australia occidental— cada una caracterizada por su propia composición local de depredadores. Los resultados muestran que la estructura del hábitat regula la depredación en todas las regiones estudiadas, pero que la dirección de la influencia depende de la composición local de los depredadores. En regiones dominadas por depredadores pelágicos, es decir peces, se observa una relación negativa entre la intensidad de depredación y la complejidad de la estructura de los hábitats. Por el contrario, en regiones donde dominan los depredadores bentónicos, como gasterópodos, la actividad de depredación aumenta con la complejidad de la estructura del hábitat. La forma en la que los hábitats se distribuyen en el espacio puede tener efectos muy fuertes sobre las interacciones depredador-presa. En el tercer capítulo se examina la influencia de las características del paisaje de una pradera de P. oceánica fragmentada sobre la depredación. Los resultados indican que un paisaje en mosaico puede generar una distribución heterogénea del proceso de depredación determinando “puntos-fríos” y “puntos-calientes” de depredación en función de la complejidad estructural de las manchas, de la presencia de roca como refugio y del grado de agregación de estas características en el espacio. En definitiva esta tesis ofrece un estudio exhaustivo sobre como varía el proceso de depredación en las comunidades de macrófitos a diferentes escalas espaciales. La presente tesis demuestra que la estructura del hábitat es un factor regulador de la depredación de erizos, un componente clave en la cadena trófica de estos ecosistemas.
Schäfer, Sabine [Verfasser]. "Reproductive disorders in sea urchins (Psammechinus miliaris) caused by environmental pollutants / Sabine Schäfer. Alfred Wegener Institute for Polar and Marine Research". Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2010. http://d-nb.info/1034994751/34.
Pełny tekst źródłaRendina, Francesco. "Effects of acute temperature increase on performance and survival of Caribbean echinoids". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10050/.
Pełny tekst źródłaStumpp, Meike [Verfasser]. "Mechanismen der CO2-Toleranz bei Seeigeln des Genus Strongylocentrotus = Mechanisms of CO2 tolerance in sea urchins of the genus Strongylocentrotus / Meike Stumpp". Kiel : Universitätsbibliothek Kiel, 2011. http://d-nb.info/1020200804/34.
Pełny tekst źródłaCavalcanti, Augusto Muniz. "Dieta do ouri?o-branco, Tripneustes ventricosus (Lamarck, 1816), no Arquip?lago de Fernando de Noronha, PE". Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12473.
Pełny tekst źródłaConselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
Sea urchins are benthic macroinvertebrates that inhabit shallow coastal waters in tropical and temperate zones. Urchins are usually classified as generalists or omnivores as they can adjust their diet according to the food resources available in the environment. Due to the strong grazing pressure they may exert, urchins have an important role in marine ecosystems, occupying different trophic levels and stimulating the intensification of the dynamics of communities where they occur. In 2004, a monitoring program focused on the population dynamics of the white sea urchin, Tripneustes ventricosus, has been initiated in the Fernando de Noronha Archipelago. At the same time, a surprisingly lack of information on the species biology has been noted, despite their wide geographical distribution and economic importance in many parts of its range. Hence, this work was developed to provide information on the feeding habits of T. ventricosus in the archipelago. Ten specimens were collected between December 2006 and July 2007 at two sites of the archipelago, Air France and Sueste Bay for biometrics and analysis of gut contents. Test diameters ranged from 9.19 cm (? 1.1) to 10.08 cm (? 0.58). Calculated stomach repletion index (IRE) was higher (p <0.05) in the Air France site and also during January and July. The IRE was not correlated to the gonad index. Fifteen different species of algae were detected in a total of 120 stomachs examined: 4 Chlorophytas, 4 Phaeophytas and 6 Rhodophytas. Food diversity (p <0.05) was higher in December 2006 and January 2007. Although several items had a high frequency of occurrence, they were low represented in terms of weight, and consequently, had a low level of relative importance. The brown algae Dictyopteris spp and Dictyota spp, followed by the green algae Caulerpa verticillata accounted for the greatest importance in T. ventricosus diet, comprising about 90% of the consumed items
Os ouri?os-do-mar s?o macroinvertebrados bent?nicos que habitam ?guas rasas costeiras em zonas tropicais e temperadas. Os ouri?os s?o geralmente classificados como generalistas ou on?voros por adaptarem sua dieta de acordo com a disponibilidade dos recursos alimentares dispon?veis no ambiente. Devido ? forte press?o de pastagem que exercem, os ouri?os possuem importante papel em ecossistemas marinhos ocupando diversos n?veis tr?ficos e estimulando a intensifica??o da din?mica das comunidades onde ocorrem. Em 2004 foi dado in?cio a um programa de monitoramento das popula??es do ouri?o-branco, Tripneustes ventricosus, quando se percebeu a car?ncia de informa??es sobre a esp?cie, apesar de sua ampla distribui??o e import?ncia econ?mica. Dessa forma, o presente trabalho visou obter informa??es referentes aos h?bitos alimentares de T. ventricosus no arquip?lago de Fernando de Noronha. Durante os meses de dezembro de 2006, janeiro, fevereiro, abril, maio e julho de 2007 foram amostrados 10 indiv?duos de T. ventricosus nas regi?es do Air France e na ba?a do Sueste. Foram realizadas biometrias e an?lises dos itens presentes no conte?do estomacal dos organismos. O di?metro m?dio de carapa?a dos ouri?os amostrados variou entre 9,19 cm (? 1,1) e 10,08 cm (? 0,58). Os ?ndices de reple??o dos conte?dos estomacais (IRE) foram mais elevados (p<0,05) na regi?o do Air France e durante os meses de janeiro e julho de 2007. Foi verificado que o IRE variou independentemente do ?ndice gonadal. Quinze diferentes esp?cies de algas foram encontradas nos 120 conte?dos estomacais analisados: 4 Chlorophytas, 4 Phaeophytas e 6 Rhodophytas, sendo que a maior (p<0,05) diversidade alimentar foi observada nos meses de dezembro de 2006 e janeiro de 2007. Apesar da freq??ncia de ocorr?ncia de alguns dos itens ser alta, suas representatividades em peso foram bastante baixas o que lhes confere um baixo ?ndice de import?ncia relativa. As algas pardas dos g?neros Dictyopteris e Dictyota, seguidas da alga verde Caulerpa verticillata representaram a maior import?ncia na dieta de T. ventricosus nas ?reas amostradas, compondo aproximadamente 90% da dieta da esp?cie no local
Dos, Ramos Catarino Ana Isabel. "Temperate and cold water sea urchin species in an acidifying world: coping with change?" Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209914.
Pełny tekst źródłaResponses of marine organisms to environmental hypercapnia, i.e. to an excess of CO2 in the aquatic environment, can be extremely variable and the degree of sensitivity varies between species and life stages. Sea urchins are key stone species in many marine ecosystems. They are considered to be particularly vulnerable to ocean acidification effects not only due to the nature of their skeleton (magnesium calcite) whose solubility is similar or higher than that of aragonite, but also because they lack an efficient ion regulatory machinery, being therefore considered poor acid-base regulators. Populations from polar regions are expected to be at an even higher risk since the carbonate chemical changes in surface ocean waters are happening there at a faster rate.
The goal of this work was to study the effects of low seawater pH exposure of different life stages of sea urchins, in order to better understand how species from different environments and/or geographic origins would respond and if there would be scope for possible adaptation and/or acclimatization.
In a first stage we investigated the effects of ocean acidification on the early stages of an intertidal species from temperate regions, the Atlantic Paracentrotus lividus sea urchin, and of a sub-Antarctic species, Arbacia dufresnei. The fertilization, larval development and larval growth were studied on specimens submitted through different pH experimental treatments. The fertilization rate of P. lividus gametes whose progenitors came from a tide pool with high pH decrease was significantly higher, indicating a possible acclimatization or adaptation of gametes to pH stress. Larval size in both species decreased significantly in low pH treatments. However, smaller A. dufresnei echinoplutei were isometric to those of control treatments, showing that size reduction was most likely due to a slower growth rate. In the pH 7.4 (predicted for 2300) treatment, P. lividus presented significantly more abnormal forms than control ones, but A. dufresnei did not. The latter does not seem to be more vulnerable than temperate species, most likely due to acclimatization/adaptation to lower pH seasonal fluctuations experienced by individuals of this population during spring time.
In a second stage, adult physiological responses of P. lividus and A. dufresnei to low pH seawaters were studied. Intertidal field P. lividus specimens can experience pH fluctuations of 0.4 units during low tidal cycles, but their coelomic fluid pH will not change. During experimental exposure to low pH, the coelomic fluid (extracellular) pH of both species decreased after weeks of exposure to low seawater pH. However, it owned a certain buffer capacity (higher than that of seawater) which did not seem to be related to passive skeleton dissolution. In laboratory studies, the feeding rate of P. lividus, the RNA/DNA ratio (proxy for protein synthesis and thus metabolism) of both the gonads and the body wall of the studied species and the carbonic anhydrase activity in the body wall (an enzyme involved in calcification and respiratory processes) of A. dufresnei did not differ according to seawater pH. The same was true for spine regeneration (a proxy for calcification) of both species. This shows that both P. lividus and A. dufresnei are able to cope when exposed to mild hypercapnia (lowest investigated pH 7.4) for a mid-term period of time (weeks). In a different set of experiments, pH effects were tested on P. lividus individuals together with two temperatures (10ºC and 16ºC). The pH decrease of the coelomic fluid did not vary between temperatures, neither did its buffer response. The oxygen uptake rates of P. lividus (as a proxy for global metabolic state of the whole organism) increased in lower pH treatments (7.7 and 7.4) in organisms exposed to lower temperatures (10ºC), showing that this was upregulated and that organisms experienced a higher energetic demand to maintain normal physiological functions. For instance, gonad production (given by the RNA/DNA ratio) was not affected neither by temperature, nor pH.
Finally, possible morphological and chemical adaptations of cidaroid (“naked”) spines, which are not covered by epidermis, to low magnesium calcite saturation states were investigated. Deep sea field specimens from the Weddell Sea (Antarctica), Ctenocidaris speciosa were studied. Cidaroid spines have an exterior skeleton layer with a polycrystalline constitution that apparently protects the interior part of the monocrystaline skeleton, the stereom (tridimensional magnesium calcite lattice). The cortex of C. speciosa was by its turn divided into two layers. From these, it presented a thicker inner cortex layer and a lower Mg content in specimens collected below the aragonite saturation horizon. The naked cortex seems able to resist to low calcium carbonate saturation state. We suggest that this could be linked to the important organic matrix that surrounds the crystallites of the cortex.
Some echinoid species present adaptive features that enable them to deal with low pH stresses. This seems to be related to the environmental conditions to which populations are submitted to. Therefore, organisms already submitted to pH daily or seasonal fluctuations or living in environments undersaturated in calcium carbonate seem to be able to cope with environmental conditions expected in an acidified ocean. Under the realistic scenario of a decrease of ca. 0.4 units of pH by 2100, sea urchins, and echinoderms in general, appear to be robust for most studied processes. Even thought, this general response can depend on different parameters such as exposure time, pH level tested, the process and the life stage considered, our results show that there is scope for echinoids to cope with ocean acidification.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished