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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Effects of CO2-induced acidification on the intertidal sea anemone Anthopleura elegantissima (Cnidaria: anthoza) and its algal symbiont Symbiodinium muscatinei (Dinomastigota: dinophyceae)

Towanda, Trisha. January 1900 (has links) (PDF)
Thesis (M.E.S.)--Evergreen State College, 2008. / "December, 2008." Title from title screen (viewed 4/8/2010). Includes bibliographical references (leaves 22-28).
22

Growth morphology and succession in a temperate marine fouling community /

Nelson, Matthew L. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2009. / Includes bibliographical references (leaves 100-103). Also available via Humboldt Digital Scholar.
23

AN ANALYSIS OF THE BURROWING BEHAVIOR OF TWO SEA ANEMONES FROM THE GULF OF CALIFORNIA

Mangum, Dorothea Caskey, 1932- January 1967 (has links)
No description available.
24

Ecologia de actiniários no entremarés rochoso: mensuração do tamanho, estrutura da comunidade e avaliação do deslocamento

Angeli, Andréa [UNESP] 10 August 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:15Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-08-10Bitstream added on 2014-06-13T20:20:39Z : No. of bitstreams: 1 angeli_a_me_rcla.pdf: 1869591 bytes, checksum: 14773e430c284b4384c16a0f78a22844 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente estudo tem como objetivos (1) realizar avaliação metodológica para determinação da medida mais adequada para estimar o tamanho das anêmonas, (2) obter dados sobre a variação temporal na riqueza, abundância e zonação das espécies de actiniários no entremarés rochoso e (3) verificar e quantificar o deslocamento de Bunodosma caissarum. Para o objetivo (1) foram tomadas variadas medidas in situ e ex situ de B. caissarum. O parâmetro morfométrico que apresentou menor variação entre campo e laboratório foi o diâmetro do disco pedal considerado, portanto, o mais adequado para estimativas de tamanho. O objetivo (2) foi estudado sazonalmente, na Praia da Enseada, Ubatuba (SP), por meio da demarcação de estratos com diferentes distâncias do limite inferior do entremarés. As espécies presentes foram Actinia bermudensis, Bunodosoma caissarum, Anthopleura cascaia, B. cangicum, Phyllactis flosculifera e um táxon não identificado. A distribuição das três primeiras espécies, mais abundantes, foi inversamente proporcional ao aumento da distância da água. As demais espécies não foram registradas em todas as estações e, com exceção do táxon não identificado, parecem ser mais relacionadas às regiões mais distantes da água. O objetivo (3) foi realizado em campo, na Ilha Urubuqueçaba, Santos (SP), e em laboratório, ambos por meio de mapeamento fotográfico. Em campo, as anêmonas em fenda apresentaram maior velocidade do que as anêmonas expostas. Em adição, demonstrou-se que sob ventos mais fortes e maiores ondas, as anêmonas deslocaram-se menos, provavelmente pela necessidade de maior adesão ao substrato. Em laboratório verificou-se a influência de organismos em contato físico, salinidade e profundidade sobre o deslocamento... / The objectives of this study are to (1) perform a methodological evaluation in order to determine the most suitable measure to estime anemones’ size, (2) obtain data regarding to seasonal variation of richness, abundance and zonation of Anthozoa species, and (3) verify and quantify the locomotion of Bunodosoma caissarum. In objective (1) several morphometric parameters of B. caissarum were measured in situ and ex situ. Pedal disk diameter showed the smallest variation among field and laboratory, this way being considered the most suitable to size estimates. The objective (2) was seasonally realized at Enseada Beach, Ubatuba (SP), through the demarcation of horizontal transects with distinct distances from the lower limit of intertidal zone. Six species were found: Actinia bermudensis, Bunodosoma caissarum, Anthopleura cascaia, B. cangicum, Phyllactis flosculifera and a nonidentified taxa. The distribution of the first three species was inversely proportional to the increasing of distance from water. The other species were not recorded in all seasons and, except for the non-identified taxa, seem to be more adapted to areas farther from the water. The objective (3) was performed in field at Urubuqueçaba Island, Santos (SP) and in laboratory both through photographic mapping. In field anemones located in fences moved faster than those in exposed sites, probably because they were in search of more favorable locations. Such conclusion matches the literature which indicates that sea anemones locomotion is associated with unfavorable conditions. In addition, it was demonstrated that anemones have lower mobility under stronger winds and larger waves probably due to the need of adhesion to substrate. It was verified in laboratory the influence of organisms in contact with anemones... (Complete abstract click electronic access below)
25

What Happened to Nemo: Population Dynamics of the Orange Clownfish, Amphiprion percula Over an Eight-Year Time Gap on Kimbe Island, Papua New Guinea

Fitzgerald, Lucy 04 1900 (has links)
Long-term studies are important for understanding the intricacies of population dynamics over time. Self-recruitment and social hierarchy are valuable tools to quantify the rates at which populations change. In mutualistic symbiosis, where two species benefit from the relationship, different selective pressures and life histories can have unintended consequences on the population dynamics of both species. Anemonefish live in a sized-based hierarchy where individuals queue to be part of the breeding pair (ranks 1 and 2). They have a mutualistic association with their host anemone; the identity of the anemone can impact their growth and fecundity. However, there is limited knowledge on the anemone lifespan and its site persistence over time. Here, we investigate rank changes and self-recruitment in Amphiprion percula and persistence in a common host anemone, Stichodactyla gigantea, on the remote island of Kimbe Island in Papua New Guinea. The populations of A. percula (n = 1,530) and their local host anemones, S. gigantea (n = 290) and Heteractis magnifica (n = 174), were sampled exhaustively in 2011 and 2019. Using DNA profiling, I determined the fate of individuals between years. We found that 21% of the A. percula population survived over the eight-year time gap compared to the 69% survival of the associated S. gigantea population in a six-year time gap. Half of the surviving A. percula individuals increased in rank and exhibited faster growth rates living on S. gigantea compared to H. magnifica. Self-recruitment was high in both years, 47% in 2011 and 39% in 2019, with one individual returning to its natal anemone. Our findings provide rare insights into one of the most charismatic symbiotic relationships in the marine environment such as the first documentation of longevity in a host anemone.
26

Distribution, diversity, and anemonefish associations of host sea anemones (Actiniaria) in the eastern Red Sea

Bennett-Smith, Morgan 04 1900 (has links)
The relationship between clownfish and sea anemones is a beloved and iconic example of marine symbiosis. However, ecological information in the eastern Red Sea about the endemic Red Sea clownfish, Amphiprion bicinctus, and its host sea anemones remains relatively incomplete. For example, previous studies report that A. bicinctus forms mutualistic relationships with three to five host anemone species in the Red Sea. But the reported number and combination of host anemone species varies substantially among sources and little is known about host anemone distributions at different scales on the eastern coastline. To better understand the ecology of A. bicinctus and its host sea anemones, we conducted 70 surveys in three regions of Saudi Arabia and one region in Djibouti. We then analyzed distribution patterns for all anemone species observed in these regions, to attain deeper knowledge of anemone habitat usage and relative abundance. We recorded six host sea anemone species associated with A. bicinctus in the Red Sea, one of which represents a new case of symbiosis, and we identified differences in species composition and abundance across different reef scales. We noted patterns of decreasing anemone diversity with increasing latitude, beginning at 20° N, and greater overall anemone abundance in the central Red Sea. We also used field and laboratory observations to examine anemonefish abundance, survival, and fecundity on different species of anemones at different life history stages. In sum, this thesis collectively identifies eastern Red Sea anemone hosts for A. bicinctus, evaluates their regional and fine-scale distributions, and assesses how different anemone species impact their anemonefish occupants on different levels.
27

The effects of anticholinergic drugs on sea anemones

Shortridge, Kenneth Robert 01 January 1959 (has links)
The first proof of the chemical mediation of nerve impulses by the peripheral release of specific chemicals was made by Loewi (1921). He demonstrated that during stimulation of the vagus nerve leading to an excised frog’s heart (Figure 1) a chemical mediator that he called Vagus-substance was released which slowed the action of the heart. This chemical mediator entered a perfusion fluid consisting of isotonic sodium chloride which was pumped out of the ventricle of the heart and diverted so as to drip onto a second frog's heart. The dripping perfusion medium slowed the pulsation of the second heart upon stimulation of the donor heart. When the stimulus was removed, the donor heart returned to normal pulsation and shortly after the recipient heart returned to normal. The Vagus-substance in the perfusion fluid was identified by Feldberg and Krayer (1933) as acetylcholine. Cholineacetylase forms acetylcholine from acetic acid and choline at the neuromuscular junction (Figure 2) in the presence of energy. The energy is obtained as a result of the action potential produced by the nerve impulse traveling along the nerve to the neuromuscular junction. The acetylcholine proceeds to cross the synapse at the neuromuscular junction and activates the muscle causing its contraction. The persistent presence of the acetylcholine at the junction would result in constant depolarization of the muscle resulting in fibrillation. The acetylcholine is destroyed by acetylcholinesterase causing repolarization so that the muscle is able to respond to further nerve impulses. Acetylcholine possesses two actions in vertebrates: muscarinic and nicotinic. The muscarinic action is exhibited at the neuromuscular functions of smooth muscle and sweat glands and the nicotine action is exhibited at the neuromuscular junction of striated muscle and at the synapse within ganglia.
28

Peachia chilensis (Carlgren 1931), a redescription of a species of parasitic, burrowing sea anemone, with a revision of Haloclavidae (Gosse 1855)

Hamilton, Natalie January 2019 (has links)
No description available.
29

The importance of fine-scale environmental heterogeneity in determing levels of genotypic diversity and local adaptation

Sherman, Craig D. H. January 2006 (has links)
Thesis (Ph.D.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: p. 161-192.
30

Snapping shrimp protect host anemones from predators

Unknown Date (has links)
The sea anemone Bartholomea annulata, is an ecologically important member of Caribbean coral reefs. This anemone serves as symbiotic host to crustacean associates, some of which may control parasite loads by "cleaning" reef fishes. Associates may gain protection from predation by dwelling with anemones. B. annulata was the most abundant anemone documented on three reefs, with 52% host to crustacean symbionts. Of those occupied by multi-species groups, 92% included Alpheus armatus shrimp. A. armatus is an important anemone associate providing protection to the anemone from predators such as Hermodice carunculata, in laboratory and field trials. H. carunculata can completely devour or severely damage prey anemones. Here I show that anemones hosting symbiotic alpheid shrimp are extremely less likely to sustain damage by predators than solitary anemones. The role of protector may be reciprocally provided by anemone and decapod associates. / by Amber McCammon. / Thesis (M.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

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