New mother Johanna stands over her calf, Zimon, Wednesday in the Planckendael, a zoological garden near Mechelen, Belgium. The little rhinoceros, born Monday, now weighs some 154 pounds. When he's grown, Zimon will have his mom's thick skin - and a horn - and he'll consume only plants. Rhinos, endangered in the wild, are native to tropical areas of Africa and Asia.