Their egg cases are sometimes referred to as mermaid's purses ... This is known to occur in sand tiger sharks (Carcharias taurus). Placental viviparity occurs in some species of shark - once the yolk ...

SYDNEY — A tiger shark has surprised Australian scientists ... Echidnas — which are only found in Australia and New Guinea — are egg-laying mammals, have spines protruding from their bodies ...

Since opening in 2002, Aqua World has been trying to breed the sand tiger shark, a viviparous species whose eggs hatch inside the womb. The keepers found the rutting season for the male shark that ...