Jacob's Sheep Breeding and Epigenetics
Another criticism I receive from atheists is in regards to the supposed unscientific story of Jacob and the spotted sheep:
Jacob took branches from white poplar trees, freshly cut almond trees, and some other trees, stripped off their bark to make white streaks, and uncovered the white part inside the branches. Then he placed the branches that he had stripped bare in all the watering troughs where the flocks came to drink. He placed the branches in front of the flock, and they went into heat as they came to drink. When the flocks mated in front of the branches, they would bear offspring that were striped, speckled, or spotted. Jacob kept the lambs separate, facing the striped and entirely black ones that belonged to Laban's flock. He set his own herd by itself and would not let them be with Laban's flock. Whenever the more vigorous of the flock came into heat, Jacob would place the branches in the troughs in front of the flock to make them mate by the branches. But he didn't put the branches in front of any of the feeble members of the flock. As a result, the feeble ones belonged to Laban, but the stronger ones belonged to Jacob.
At first reading, it's peculiar to see a herdsman use visual aids at the moment of conception to affect the progeny of animals, with the intention of producing a particular breeding effect. The coloring is determined by what the parents see during intercourse. However, further details in this passage showcase a complete compatibility with modern epigenetics. The flock tended by Jacob had only monochrome animals with respect to phenotype. However, in regards to genotype, 33% were pure monochromes (homozygotes), and 66% were heterozygotes (containing the gene of spottedness). By crossing the heterozygotes among themselves, Jacob would produce 25% spotted sheep.
Furthermore, poplar trees contain salicin (an anti-inflammatory related to aspirin). This species of poplar was the Populus alba. The almond tree is the Amygdalus communis. Notice that Jacob "stripped" them and placed them in the watering troughs, since the stripping of wood is simply a method of leaching the chemicals into the water.
Thus, a fascinating 2008 paper by Joshua Backon (from the Department of Pharmaceutics at the Hebrew University of Jerusalem) was published examining this in light of recent advances in epigenetics. In this paper, Backon showcases how prenatal nutrition can affect the agouti gene that regulates fur color in both sheep and mice. The fungi that resides in the bark of these specific types of branches of poplar and almond provide the chemicals that comprise the exact amino acids to create alterations in the color of fur without having any direct affect on the DNA.
More fascinating is the fact that Augustine (4th century Bishop of Hippo) showcases a hint of biological sophistication by commenting: "And that the lambs conceived were colored as an effect of the particolored rods was due to the souls of their pregnant mothers being affected from the outside through their eyes and having inside them their own proper program of embryo formation which they received from their Creator, whose power was active at the inner roots of their being."