#8 – Long Gestation Period
Most sharks have a long gestation period, i.e. they have a long pregnancy. For example, the basking sharks have a gestation period of approximately two years. Just imagine being pregnant for two years! However, not all sharks have a long gestation period. For instance, the bonnet head sharks have a gestation period of only a couple of months.
Animals that have the longest gestation period in the world are elephants, whose pregnancy lasts 22 months on average.