Because if there is a minimal variation of it the normal state of pH, it can cause severe effects in the brain, arteries, the heart, and other organs.
In other words, it can have some serious effects on the body systems that can lead big diseases, like cancer.
The natural selection is the survival of the fittest, which means that o<span>nly the best adapted individuals survive and reproduce, contributing the most to the next generation</span>
According to natural selection, birds such as cardinals , eagles, and ducks have differently shaped feet due to <span>adaptation to different environments and feeding habits.
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<span>The first part of the question is: The male's ability to shake its tail is the mechanistic cause of this behaviour. For the second part of the question, the mate choice is the adaptive function of this behaviour.</span>
C. Decreased death rate is the answer
