Adaptation is considered as a characteristic that increases the survival or reproduction rate of an organism. These traits or characteristics could be examined under natural selection or as a feature that is best fit to survive during evolution. An example of adaptation could be seen in the rainbow trout. They are known for using hormone regulation, migration and specific mechanisms to help them survive. Such features are known for increasing their ability to survive and adapt when migrating to and fro different environmental conditions. In this paper, some of these mechanisms/methods will be examined.
The rainbow trout is also known as steelhead and has been classified as a member of the genus Oncorhynchus (Oncorhynchus mykiss). This genus of species is known for migrating to the sea as a juvenile and for returning to fresh water as an adult when they are ready for spawning. Their ability to survive, has allowed biologist to observe, examine and explain the function of these physiological structures and their role in adaptation - but first, their phylogeny will be examined.
The rainbow trout is known for not dying after spawning and for surviving for up to 8 years – in comparison to the Pacific salmon and other Atlantic salmon. However, many biologists wanted to know how they were able to survive and which genus of species they were closely related to. After several sequencing and genetic studies, it was then determined that they originated from Pacific salmon. Based on the results, they were found to have similar growth hormone genes. The two types of growth hormone genes were isolated and sequenced from sockeye salmon (Oncorhynchus nerka). The genes encoded proteins of 210 amino acids and showed considerable similarity to gr...
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...rate to the ocean. This reproduction process is considered a very vital stage of salmon development and it is from here one can determine whether they will survive. However, it is likely that the larger trout will show aggression to the juvenile or smaller trout (competition/predation).
The rainbow trout are found to be remarkable species. Evidence of their ability to adapt and to use their traits have been evidently advantageous, increasing their ability to survive during development and migration. It is evident they are not able to reproduce without spawning, and without migration they cannot spawn. This concludes that as a result of evolution, their environmental instincts and physical maturation, they have been able to adapt. Regardless of natural selection and predators, it is evident that because of their traits that have been able to survive the longest.
Schilt, C. R. (2007). Developing fish passage and protection at hydropower dams. Applied Animal Behaviour Scence, 104, 295-325.
In the past, because the glaciers disappeared slowly can make people have a low temperature, clean water during the summer, but at the same time the salmon begin and end their lives. With temperature getting warmer and our glaciers melting, every stage of salmon’s life cycle is getting hurt.
The PBS documentary begins by explaining the normal life cycle of salmon, focusing primarily on the sockeye salmon population. This Pacific salmon once was found abundantly in the Columbia and Snake River, but as rivers were straightened and dams were built to meet the needs of population growth the fish population has diminished by the thousands.
An adaptation is the characteristic of an organism that makes it likely to survive. There are three types of adaptations: structural, physiological, and behavioural. Structural adaptations are physical features, physiological adaptations are related to the internal body functions, while behavioural adaptations refer to how organisms respond to stimuli (Beavis 2014). This paper will discuss some adaptations that help koalas and eucalyptus trees survive in their environments.
The salmon are all sterile females which are grown in contained land-based systems, therefore they will not be able to breed among themselves or with other fish. So it is unlikely that the fish will have an impact on wild populations.
Since three-forth of the world is composed of bodies of water, it’s natural that a great number of people rely on fishing for their livelyhood or just for their recreation needs. There are numerous of fish species swimming under the lakes, seas, ponds, and rivers. Most anglers consider fishing as the delight in their purpose-driven life, a sport, as they say.
In The Rainbow Fish by Marcus Pfister tells how a beautiful, extraordinary, yet, self-centered blue fish learns that being beautiful isn’t the key to happiness. The blue fish came to find this lesson when he lost his friends. Pfister takes a simple ocean setting and explores the consequences of an individual’s arrogance toward their peers, the process of humbling of oneself, and the tremendous reward one feels when they learn to share. The story achieves these morals by the author’s use of detailed imager and also, the influence of minor characters on the antihero in order to reveal to the audience the true thematic message; selfish actions bring true happiness.
The Artemia franciscana can survive in extreme conditions of salinity, water depth, and temperature (Biology 108 laboratory manual, 2010), but do A. franciscana prefer these conditions or do they simply cope with their surroundings? This experiment explored the extent of the A. franciscanas preference towards three major stimuli: light, temperature, and acidity. A. franciscana are able to endure extreme temperature ranges from 6 ̊ C to 40 ̊ C, however since their optimal temperature for breeding is about room temperature it can be inferred that the A. franciscana will prefer this over other temperatures (Al Dhaheri and Drew, 2003). This is much the same in regards to acidity as Artemia franciscana, in general thrive in saline lakes, can survive pH ranges between 7 and 10 with 8 being ideal for cysts(eggs) to hatch (Al Dhaheri and Drew, 2003). Based on this fact alone the tested A. franciscana should show preference to higher pH levels. In nature A. franciscana feed by scraping food, such as algae, of rocks and can be classified as a bottom feeder; with this said, A. franciscana are usually located in shallow waters. In respect to the preference of light intensity, A. franciscana can be hypothesized to respond to light erratically (Fox, 2001; Al Dhaheri and Drew, 2003). Using these predictions, and the results of the experimentation on the A. franciscana and stimuli, we will be able to determine their preference towards light, temperature, and pH.
Ashley Dean, Shwartz,.Mark 2003. Salmon farms pose significant threat to salmon fisheries in the Pacific Northwest, researchers find. Stanford University
The stories of each fish flow together as each story shows how humans have pushed to gain more control over the ocean and the delicious animals that swim in it’s depths. Greenberg starts in the free-flowing rivers where salmon are commonly found. It is there that early humans of the Northern Hemisphere most likely began their infatuation with fish. Greenberg puts it as, “It(salmon) is representative of the first wave of human exploitation..” (170) Once Europeans learned to fish, they had the ability to fish in shallow ocean water which is where sea bass are usually found. Later, fishermen s...
middle of paper ... ... that occurs is only that which allows for a species to adapt to its present circumstances. As the examples given here illustrate, natural selection may take on many forms and give a species better defensive, offensive, or reproductive measures in the struggle for existence, which, though it sounds dramatic and urgent, is nothing more than being able to effectively cope with the external world and reproduce. Works Cited Darwin, Charles. The Origin of Species.
One should not think that because zebrafish (Danio rerio) are fishes that they are in some ways less than any mammalian species. They certainly are not. Zebrafish are small shoaling cyprinids, named after the prominent black and white stripes patterns of the adults. Native to the Indian subcontinent, those laterally compressed organisms are widely distributed in slow moving streams and stagnant habitats. Where existent, zebrafish are typically the most abundant species (McClure, et al., 2006, p. 562). They also have a short generation time which allows large numbers to hatch in a short period of time. The species has become popular among enthusiasts due to its hardiness, cold resistance, and facility of breeding. Over the years, selective breeding have created numerous different strands.
According to Darwin and his theory on evolution, organisms are presented with nature’s challenge of environmental change. Those that possess the characteristics of adapting to such challenges are successful in leaving their genes behind and ensuring that their lineage will continue. It is natural selection, where nature can perform tiny to mass sporadic experiments on its organisms, and the results can be interesting from extinction to significant changes within a species.
Freshwater fish and saltwater fish are very similar in a lot of ways, but also have differences between them so you can tell them apart. Marine water (saltwater) equals over 96 percent of the water on Earth and over 70 percent of Earth’s total surface. Freshwater is less than four percent of Earth’s total water and is about one percent of Earth’s surface (Freshwater Fish). Interestingly a few species of fish can live in either freshwater or saltwater, but for the majority, they must live in a specific environment. All species of fish used to live in a saltwater environment until certain geological events (earthquakes, volcanic activity, etc.) occurred, creating conditions that isolated groups of fish. The new habitats, included freshwater, and new food sources caused fish to either adapt, or to die (Lohrey).
Since salmon do not feed once they leave the ocean, some will die on the way because they lack enough stored body fat to make the trip. Many will be caught in fishermen's nets. Those that evade the nets may have to swim through polluted waters near cities. Many must make their way over power dams, leaping up from one tiny pool to the next along cement stairstep cascades called fish ladders. In the tributary streams, waterfalls and rapids are steep and swift enough to eliminate all but the strongest. Otters, eagles, and bears stalk the salmon in shallow riffles. Once on the spawning grounds, the fish battle each other: females against females for places to nest, males against males for available females.