In deep waters, organisms must adapt to survive stresses absent in surface waters, such as extreme pressure, lack of light, food scarcity, toxic chemical flows and other factors. which make it difficult to flourish in life. Symbiotic relationships – the interaction between two different organisms that share a close association – allow organisms to better survive predation, starvation and habitat variability. In cases of mutualism, both parties benefit from the association in various ways. By studying the interactions of these various species, it is possible to reveal to what extent organisms are able to evolve and acclimatize in this extreme environment in order to persist there, by co-dependence or simply by exploiting certain characteristics of each . Say no to plagiarism. Get a tailor-made essay on “Why violent video games should not be banned”? Get an original essay In well-established mutualistic relationships, species can shape their morphology to support their interactions. This is the case of the hydrothermal vent shrimp Rimicaris exoculata. The crustacean has a dense covering of bristles in its mouthparts that house the bacterial epibionts – Epsilonproteobacteria and Gammaproterobacteria – which it needs to oxidize sulfur and iron compounds expelled from ventilation fluids. To support even more possible ectosymbionts, the species has evolved a large cephalothorax whose inner side supports the setae. R. exoculuta obtains a rich source of nutrition from these symbiotic chemoautotrophic bacteria, supposedly through trans-epidermal mechanisms. In turn, the ectosymbionts live in an optimal microenvironment exposed to a constant supply of electron donors and acceptors from vent expulsions, whereas the shrimp migrate to richer waters where vent currents are stronger to improve the productivity of bacteria (Jillian Peterson). GURI studied the structure of ectosymbionts throughout the different stages of the wind shrimp's life. Shrimp have been found to interact with bacteria early in their life cycle, as the gammaproteobacteria present in the mucus surrounding the eggs can serve as a protective device enabling detoxification and defense against pathogens. The Peterson study of these epibionts found that there was variation in bacterial dominance with changing geochemical locations of shrimp between oxidized seawater and chemical fluxes, suggesting that comparing distribution patterns of these symbiotic bacteria will help to understand the evolutionary processes of migration and symbiont-host associations. These studies show that the two organisms have developed a stable mutualistic relationship that allows them both to survive in this harsh environment. Allantactis parasitica and various deep-sea gastropods along the eastern coast of Canada, at depths of up to 1,100 m, have established a facultative mutualism resulting from predation pressures on both species. A. parasitica selects specific positions on the shells based on its own body size. Mainly, gastropod species deter predators such as Leptasterias polaris thanks to the presence of one or more anemones present on its whorl. The anemone almost always has its tentacles elongated, creating a shielding effect that makes the gastropod even more invisible to these predators. Mericer Hamel 2008 discovered that in 100% of the cases studied, thepredators made no obvious effort to approach the gastropods in the presence of anemones. In turn, A. parasitica is protected from Crossaster papposus because the disrupted movements of the gastropods make it more difficult for the anemone to be captured by the starfish. Although the two species are not codependent on each other , studies have shown that throughout the life cycle of A. parisitica, even from juvenile stages, the species will choose to move towards a living surface rather than towards a soft sediment surface. Other advantages of this symbiotic relationship are that the life of the anemone associated with a gastropod results in greater reproductive and growth success (reproduction + settlement). Researchers discovered that A. parasitica grew twice as fast as juveniles due to a greater supply of food made available by the upwelling of nutrients when its gastropod counterpart moved. The species also reached its adult peak after 6–7 years, compared to its asymbiotic parents, which reached this level of growth after at least 11 years. It has also been observed that the largest anemones position themselves on the last whorl of the shell in order to have optimal access to the food made available by the burrowing actions of the basibiont. Small anemones, including juveniles, are located further off the ground because they are less likely to be pushed out of the shell or smothered by the amounts of particles disturbed by gastropod movements. During studies on Rhinoclavis it was observed that 4 to 6 anemones could even be found in the shell groves because the siphonal canal could protect the epibionts from scratching during the gastropod's movements, A. parasitica was also observed to synchronize spawning periods with those of gastropods in 52% of cases studied by Reproduction People. The congregation of species such as Neptunea despecta and Colus stimpsoni to reproduce resulted in the anemone species being in close association when positioned on the whorls. By spawning at this time as well, fertilization rates were maximized. The anemone was also affected by the diet of its basibiont, as Feeding People found that its asymbiotic counterparts had a much less diverse diet, with fewer bathhyl organisms present in their gastrovacular cavity. This suggests that sediment from feeding snails makes different food particles available to A. parasitica, more often throughout the day. Once predators are deterred, gastropods can feed for longer, uninterrupted periods and anemones can exploit a constant supply of rich food sources. There are now 17 evolutionary accounts of bioluminescence in ray-finned fishes in association with symbiotic bacteria. it is unclear whether participants coevolved together over time. The relationships between host and bacteria are quite fluid, with fish organs harboring diverse bacterial populations, not just one, and microbial symbionts coming into contact with many other species. Although there is little or no host specificity between bioluminescent bacteria and their hosts, this relationship is clearly important to both parties as it has continued to develop. Fish, which obtain bacteria from their local environment, use the light produced to attract prey, camouflage, defend themselves and communicate. The bacteria, which break down luciferin compounds using luciferase in the presence of oxygen to generate light, are well accommodated by their hosts, which.