While reading today's torah portion, which covered the birth of 11 sons and a daughter of Jacob, I pondered how closely spaced the ages of the kids would be. Jacob worked for Laban for 20 years. The first seven were as a bachelor. He then marries two women one week apart. Here's the following scenario:
Leah conceives and bares Reuben
Leah conceives again and bares Simeon
Leah conceives again and bares Levi
Leah conceives again and bares Judah
Rachel is barren and gives her handmaid, Bilhah, to Jacob
Bilhah conceives and bares Dan
Bilhah conceives again and bares Naphtali
Leah then gives her maid, Zilpah, to Jacob
Zilpah conceives and bares Gad
Zilpah conceives and bares Asher
Leah "purchases" a night with Jacob
Leah conceives and bares Issachar
Leah conceives and bares Zebulun and Dinah
Rachel finally conceives and bares Joseph
In Genesis 30:25, after Joseph was born, Jacob asked to leave Laban, but Laban asked Jacob to stay to earn flocks. Verse 31:41 clarifies that he worked fourteen years for the daughters and six years for the cattle. So, all the children seemingly were born in the second seven years, before all the cattle mating. This verse also tells how Laban changed his wages ten times, suggesting that several years have passed during the cattle section as Laban sees the outcome of the various matings.
So, in seven years, Leah seems to have had six pregnancies.
I checked this chronology in the Book of Jubilees and found this:
year (year of Jacob's service) birth
2122 (8) 9/14 - Reuben
2124 (10) 10/21 Simeon
2127 (13) 1/1 Levi; 6/9 Dan
2129 (15) 3/15 Judah
2130 (16) 7/5 Naphtali
2131 (17) 8/12 Gad
2132 (18) 5/4 Issachar
2133 (19) 11/2 Asher
2134 (20) 1/4 Joseph; 7/7 Zebulon & Dinah
2135 1/21 fled; 3/13 Laban overcomes Jacob
While this seems to be an easier pace of childbearing, there are two issues. the first is that the cattle appear to have multiple bearings after this arrangement is made, both in the description of the end of Genesis 30, and the fact that Laban changed his wages ten times. Average gestation time for a sheep is 150 days. Typically sheep go into heat after the fall equinox, are sheared right before birth in the spring, and nurse their young for up to six months, when they start to go into heat again. It is possible for lambing to occur as frequently as about every 8 months the closer one lives to the equator.
The second issue is the timing. Genesis said that Jacob had fled for three days before Laban was told. Then Laban pursued for seven days, for a total of ten days. However, Jubilees records that Laban overcame Jacob almost two months later.
Any ideas on how to reconcile these?