They are strong swimmers, aided by their strong forearms and layer of blubber for buoyancy. They have a large layer of blubber to keep them warm. Polar bears are well adapted to life in the Arctic.

In other words their structure allows them to function in that environment.Where and how an organism lives is largely due to its specific adaptations that allow it to survive and reproduce in a particular area or habitat.The product of natural selection is the adaptation of populations of organisms to their environment.Natural selection occurs through an interaction between the environment and the variability inherent among the individual organisms making up a population.Developmental: Variable changes that occur across the life span of an organism (e.g.Biochemical: Differences in molecular composition of cells and enzyme functions (e.g.Physiological: Variations in detection and response by vital organs (e.g.Behavioural: Differences in patterns of activity (e.g.Structural: Physical differences in biological structure (e.g.Evolution – Over time, there is a change in allele frequency within the population gene poolĪdaptations are features of organisms that aid their survival by allowing them to be better suited to their environment adaptations may be classified in a number of different ways:.Adaptations – Individuals with beneficial traits will be more likely to survive and pass these traits on to their offspring.Selection – Environmental pressures lead to differential reproduction within a population.Competition – There is a struggle for survival (species tend to produce more offspring than the environment can support).Inherited Variation – There is genetic variation within a population which can be inherited.The process of natural selection occurs in response to a number of conditions: If there was no variation within a species, then all individuals would be the same and no individual would be favoured over the other and natural selection would not take place. Individuals that are best suited for their environment will survive and reproduce. Within a species, different individuals of that species show genetic variation. According to this theory, it is not necessarily the strongest or most intelligent that survives, but the ones most responsive to change. The theory of natural selection was posited by Charles Darwin (and also Alfred Wallace) who described it as ‘survival of the fittest’.

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