Use what you know about natural selection to fill in the blanks in the hypothesis. it should answer the lab question, “what is the effect of the type of food available on the frequency of different types of bird beaks? ”

If the food type changes in a given environment, then the amount of each type of bird beak will change as birds with beaks more suited to the available food will consume more successfully over time. The independent variable of the lab is the type of food that is available to the birds. The dependent variable of the lab is the frequency of each type-size and shape-of beaks. The conclusion will state that favourable traits place one species in a more optimal position to survive in a given envronment.

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If the type of the food available changes, then the frequency of beak types will change, because birds with beaks more suited to the available food will be more successful over time.

the darker peppered moth species were favored due to the fact that the industrial revolution had made all the nearby trees a darker color instead of white.

the answer is d.) homologous; have mammary glands