Elephants have the longest gestation of any creature on the planet. Asian elephant gestation periods last anywhere from 18-22 months, while African elephant gestations last a full 22 months .

Now, Colossal has announced that it's not only made a prototype for an artificial uterus, but also used it to culture ...

Either way, the next step would be to implant the resulting embryo into the womb of a modern-day female elephant. After 22 months—the typical elephant gestation period—an ice age mammoth ...

They give birth to a 105 kg calf, which first has to gestate in the mom's womb for nearly two years! More than twice as long as a human pregnancy! Close behind elephants are giraffes. They drop a ...