“And Yaakov took moist stick[s] of cedar, and of almond and of plane and he peeled them [making] white peelings” (B’reishis 30:37). Although there are different translations given for the types of trees Yaakov used, the bottom line is that he peeled away parts of the bark so that the branches were now multi-colored, in order to increase the number of multi-colored animals born to the flocks he was tending. Much has been written about how putting peeled branches in the watering troughs affected the number of multi-colored animals born; I have not seen much written about why it matters how Yaakov tried to increase those numbers. I would think that all we need to know is that the “wages” Yaakov would receive from Lavan were the multi-colored animals born, that Lavan tried to minimize how many Yaakov would get by changing the terms of the agreement (see 31:7-8 and 31:41), and that G-d made sure there were many, many multi-colored animals born despite Lavan’s dishonesty. Before discussing why the Torah spends several verses describing how Yaakov tried to increase the number of multi-colored animals born, let’s take a closer look at how putting partially peeled branches in the watering troughs could make a difference.

Despite Lavan removing all the multi-colored animals (30:35), genetics (heterozygosis)would still dictate that some of the newborn animals would be multi-colored; if two sheep (or goats) having a recessive “colored” gene mated, one of every four sheep born to them would have both recessive genes, and would therefore be multi-colored. By the next mating season, those multi-colored animals that mated with each other would have multi-colored offspring, as would half of those that mated with animals that only had one recessive gene. Lavan likely knew this, as did Yaakov, as otherwise no multi-colored offspring could be expected, and there would be no reason for Yaakov to stay. The question is not how any multi-colored animals were born, but how the peeled branches affected how many were born.

Rashi, quoting B’reishis Rabbah, brings two approaches. The first, that the branches startled the females, making it easier for the males to impregnate them, seems to at least partially work within the laws of nature (increasing the mating opportunities) while implying that the females being taken aback by seeing the peeled branches somehow caused them to give birth to animals with an appearance similar to those that startled them. Increasing the number of mating opportunities alone would increase the number of multi-colored animals born, although it would increase the number of monochromic animals born as well. Dr. David Neustadter (http://www.vbm-torah.org/alei/13-08sheep-neustadter.rtf) makes a similar suggestion, referencing the verse (30:38) saying that when the sheep came to drink, they “became hot,” thereby increasing the fertility rate of the sheep. Aside from the implication that the peeled branches only affected how many multi-colored animals were born, if Yaakov knew that such visual stimulation increased the fertility rate, we would have expected him to have done so well before he started working for himself.

Dr. Neustadter adds another possibility, suggesting that being visually stimulated by peeled branches made it more likely that the females would prefer to mate with those having a similar appearance, thereby increasing the number of multi-colored offspring. (If this were the case, Yaakov must have waited until the second mating season to peel the branches, as initially there were no multi-colored males to prefer.) Rashi doesn’t explain why or how the offspring would look like the peeled branches, but it would be fair to apply the reason most prevalent in the traditional literature, that seeing something during conception (or shortly beforehand) affects the physical characteristics of the fetus (see Midrash HaGadol on 30:39). Although this has no known basis in scientific fact, it was apparently a widely held notion. If Yaakov thought it would help, we can understand why he would try it. However, it makes the question of why the Torah included it in the narrative that much stronger.

Rashi’s second approach, or perhaps an added facet to his original approach (as he does not say it is a new thought, just quotes Rav Hoshiya, who might be adding to what was said until now), is that the water the females were drinking turned into “seed,” obviating the need for a male. It can be assumed that the “characteristics” that the male would have contributed now came from the water, within which the peeled branches were sitting, causing the offspring to resemble the branches (multi-colored). This approach is obviously not working within the laws of nature (see Mizrachi). It is doubtful that Yaakov expected the water to turn into “seed” by placing the peeled branches within it. It should be noted that if the water turning into “seed” was necessary for the peeled branches to have any real affect, the females merely seeing the multi-colored peeled branches could not have been enough to cause the ratio of multi-colored offspring to increase.

Another possibility has recently been put forth (see http://jbq.jewishbible.org/assets/Uploads/364/364_sheep.pdf) based on the concept of epigenetics (see http://www.rachel.org/files/document/Nine_popular-press_articles_about_epigenetics.htm). To quote Dr. Joshua Backon, “Epigenetics is the study of heritable changes in gene expression that occur without a change in DNA sequence…What is most relevant to the biblical story of Jacob and the sheep is the research on early nutritional influences on the Agouti gene affecting coat color of fur in sheep and mice.” In other words (and Dr. Backon provides more detail), placing these three kinds of branches in the troughs, specifically after exposing the inside of the bark through the peeling process, may have released certain fungi containing specific amino acids into the water that could affect the color of the fur of the offspring of the animals that drank it. This could explain why Yaakov used three different types of trees rather than just one, although the Midrash (Lekach Tov and Seichel Tov) attributes his choice of trees to their names (representing the city where G-d appeared to Yaakov, possibly reminding himself of G-d’s promise to him or as a reminder that all he had asked for was “clothing to wear and bread to eat” (28:20) so as not to get too forlorn over Lavan trying to trick him out of any real income; representing Lavan himself; and representing Lavan’s deceitfulness). It is also possible that Yaakov thought the animals seeing the peeled branches would be enough and chose those specific branches for symbolic reasons, with divine providence making sure that he did things in a way that worked within the laws of nature. Either way, epigenetics could explain how Yaakov putting peeled branches of wood in the animals drinking water caused a much higher rate of multi-colored offspring. [Could Rav Hoshiya saying that the water turned into “seed” really mean that the water now had the ability to affect the characteristics of the offspring the way “seed” usually does?]

When Yaakov describes the prophetic dreams he had when the sheep were mating (31:10-12), he says that they were mating with multi-colored sheep that G-d’s angels had brought over from Lavan’s flocks (see Rashi) in order to compensate for Lavan having oppressed him. The implication is that it was G-d’s direct intervention that caused so many multi-colored sheep to be born, not putting peeled branches in the water. This doesn’t negate the possibility that the peeled branches helped (but needed G-d’s intervention to be as successful as it was), but it does bring us back to the question we posed earlier: If it came down to G-d helping Yaakov be more successful than he would have otherwise been, why is the peeling of the branches described so prominently in the Torah’s narrative? Does it really matter how Yaakov tried to achieve success? Were the peeled branches even a substantial part of his success? Is the Torah giving us a science lesson to “try at home”?

Some could suggest that the peeled branches were included in order to introduce us to the concept of things we see and think about affecting us. And this is certainly true on a spiritual level and, to a certain extent, on a physical level as well (as our bodies respond to such stimuli). However, it does not seem to be true at the genetic level, making it hard to accept that “bad science” was purposely included in the Torah in order to teach us this valuable lesson. Granted, science is a moving target; until a couple of decades ago scientists would have laughed at epigenetics. Nevertheless, until there is a strong enough reason to think otherwise (and Rabbi Akivah saying so to a king in order to promote marital harmony does not prove it really works), it is fair to assume that merely seeing something does not have a genetic affect. There seems to be a more basic message that the Torah is trying to get across by highlighting how Yaakov tried to increase his wages.

The very fact that Yaakov agreed to stay for years with Lavan even after Yosef was born (when he was ready to leave; see 30:25) indicates that he was willing to work in order to support his family rather than only relying on G-d to provide for him (despite the blessing from Yitzchok that he would be wealthy, see 27:28), or relying on Yitzchok’s wealth. Was “getting a job” enough? Did agreeing to work for Lavan, thereby creating a “natural” means for G-d to fulfill Yitzchok’s blessing, qualify as appropriate “hishtadlus” (natural effort) without needing to do more? By relating to us the lengths to which Yaakov went to increase his wages, the Torah teaches us that our efforts are not to be kept at a minimum; we should do whatever we can (within reason) to improve the chances of financial success. Much as the Talmud sharing with us (sometimes at length) medical, financial and interpersonal advice teaches us that we should do what we can to maintain our health, attain financial success and build solid relationships, the Torah detailing the lengths Yaakov went to make a good living teaches us that we must “sweat the details” as well. From this perspective, it doesn’t really matter whether peeling the branches actually worked; the point is that Yaakov thought it would (and it might have), so he peeled branches and put them in the animals’ water.