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Natural Selection. [Choose the most correct answer from the following multiple choice questions] . Start quiz!. 1. What aspect of ‘fitness’ is most important for species survival?. Speed Strength Reproductive ability.
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Natural Selection [Choose the most correct answer from the following multiple choice questions] Start quiz!
1. What aspect of ‘fitness’ is most important for species survival? Speed Strength Reproductive ability
2. In the context of Natural selection what does “population variation mean” ? When living things from the same species have different characteristics. For example some field mice might have a tanned coat and some might have a white coat etc. When living things from the same species have the same characteristics. When living things from different species have the same characteristics. For example bats and eagles have wings used to fly.
3. In the context of the concept of natural selection reasons a population of any species have different characteristics is because ? They only inherit those different characteristics from their parents. They try to change their characteristics during their lifetime to adapt to their current environment for example: Giraffes try to stretch out their long necks. Populations of any species have different characteristics because: they inherit those characteristics, a percentage of genes / characteristics are not passed onto offspring but are random and/ or they involuntarily mutate during their lifetime.
4. ‘Changes in the environment’ leading to ‘Natural selection’ refers to: Factors in the environment of a species that cause the population of the least fit of that species to die off and the most fit of that species to repopulate. For example, the migration of predators to that environment. Changes in the environment only refer to the changes in the weather affecting the survival of the species. Changes in the environment only refers to for example new species of plants that have become abundant in the habitat of a population of plant eating animals, therefore causing those animals that can eat this type of plant to become abundant.
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Natural Selection Now that we have identified some of the sources of variation between organisms, and we have determined what fitness is –What are the mechanisms by which Natural Selection occurs?
Natural Selection Mechanisms There is variation in traits. For example, some beetles are green and some are brown. • There is differential reproduction. • Since the environment can't support unlimited population growth, not all individuals get to reproduce to their full potential. In this example, green beetles tend to get eaten by birds and survive to reproduce less often than brown beetles do.
Natural Selection Mechanisms There is heredity. The surviving brown beetles have brown baby beetles because this trait has a genetic basis. • End result:The more advantageous trait, brown coloration, which allows the beetle to have more offspring, becomes more common in the population. If this process continues, eventually, all individuals in the population will be brown.
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