Although most salamanders have four legs, the aquatic salamander shown below resembles an eel. It lacks hind limbs and has very tiny forelimbs. Propose a hypothesis to explain how limbless salamanders evolved according to Darwin's theory of natural selection.
From wiki:
Natural selection is the process by which certain heritable traits—those that make it more likely for an organism to survive and successfully reproduce —become more common in a population over successive generations. It is a key mechanism of evolution.
So, what are the reasons for having lack of hind limbs and has very tiny forelimbs?
Survival, most likely.
So, state a hypothesis which states the limbless salamander evolved because of (definition of natural selection).
To propose a hypothesis on how limbless salamanders evolved according to Darwin's theory of natural selection, we need to consider the principles of natural selection and the adaptations that could have contributed to the evolution of limblessness in aquatic salamanders.
1. Variation: Within a population of salamanders, there may have been some individuals with variations in their limb development or structure. This variation could have been due to genetic mutations or other factors.
2. Selective Pressure: The environment in which these salamanders lived likely played a role in the selection for limblessness. Aquatic environments with dense vegetation or narrow crevices might have provided selective pressures that favored individuals who were more adapted to such environments.
3. Reproduction: The individuals with variations in limb development who were better adapted to their aquatic environment would have had an advantage when it came to survival and reproduction. This advantage could have been due to increased mobility, the ability to navigate through tight spaces, or more efficient hunting techniques.
4. Adaptation: Over time, the individuals with limb variations advantageous to their environment would have had a higher chance of passing on their genes to the next generation. As this process continued over many generations, the genes responsible for limblessness would become more prevalent in the population.
5. Natural Selection: The individuals with limblessness would have had a greater fitness in their specific environment, increasing their likelihood of survival and reproduction. Through natural selection, traits that provided an advantage in an aquatic environment, such as limblessness, would become more common in the population.
Hence, the hypothesis could propose that limblessness in aquatic salamanders evolved due to selective pressures in their environment, and over time, those individuals with variations in limb development that provided an advantage for survival and reproduction were more likely to pass on their genes, leading to the evolution of limbless salamanders.