Square Feet. The square foot is a unit of area used in the imperial and U.S. customary measurement systems. A square measurement is the two-dimensional derivative of a linear measure, so a square foot is defined as the area of a square with sides 1 ft in length.
16 Months of Patience. The white rhino is one of the largest of all rhino species, so it's not surprising that her large stature would lead to a long gestation period of 15 to 16 months. After the gestation period, the mother gives birth to a single calf weighing around 143 pounds.
Both African and Asian elephants have a pregnancy that approaches two yearsâ22 months, to be exact. This is the longest gestation period for any land animal, and one âof the longest for any animal on earth. Elephants produce one baby at a time, and the youngster weighs around 105 kilograms (230 pounds) at birth.