However, it's important to note that this period is not solely determined by the time the embryo develops inside the mother. Here's why:
* Delayed Implantation: Polar bear embryos don't implant in the uterine wall immediately after fertilization. The fertilized egg can remain dormant for several months before implantation.
* Actual Development: The actual development of the embryo happens in the last two months of the gestation period.
So, while the overall gestation period is long, the actual time spent developing inside the mother is shorter. This adaptation helps polar bears give birth in the safety of a snow den when food is scarce.