Sensory systems enable organisms to obtain needed information. Consider:
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A frog, which feeds on flying insects, has eyes with receptor cells that fire only in response to small, dark, moving objects. A frog could starve to death knee-deep in motionless flies. But let one zoom by and the frog's "bug detector" cells snap awake.
A male silkworm moth has receptors so sensitive to the odor of the female sex-attractant that a single female silkworm moth need release only a billionth of an ounce per second to attract every male silkworm moth within a mile. That is why there continue to be silkworms.
We are similarly designed to detect what are, for us, the important features of our environments. Our ears are most sensitive to sound frequencies that include human voice consonants and a baby's cry.
Nature's sensory gifts suit each recipient's needs.