What Does Genesis 30:37 Mean?

Then Jacob took fresh sticks of poplar and almond and plane trees, and peeled white streaks in them, exposing the white of the sticks. Jacob's selective breeding strategy involves two elements: the peeled sticks (verses 37-39) and the selective exposure of specific breeding pairs to the sticks (verses 40-42). The sticks of poplar, almond, and plane are peeled to expose white streaks in an alternating pattern with the bark's natural color. The belief underlying the practice was that what a female animal saw at conception would influence the coloring of her offspring.

The practice of using visual stimuli to influence prenatal outcomes was widespread in the ancient Near East as a folk belief about animal breeding. Modern genetics has definitively shown that visual stimuli do not influence coat color; the outcome of Jacob's breeding was produced by selective genetic pairing rather than by the sticks themselves. The narrator presents Jacob's stick strategy without evaluating its scientific validity. That the strategy appeared to work is noted; the mechanism is not endorsed.

God's own explanation to Jacob in Genesis 31:10-12 attributes the outcome to divine intervention in the dream: the angel showed Jacob that God was directing the breeding outcomes. The sticks may have been Jacob's best understanding of how to pursue the result he sought, but the actual result came from God's management of the genetics. Jacob's action plus God's blessing produced the outcome; the sticks were neither scientifically effective nor entirely beside the point if they represented Jacob's faithful effort to act within the agreement.