National Geographic Channel has a new special - In the Womb: Extreme Animals - which uses "4-D ultrasound images" to follow the gestation of four different critters: red kangaroo, lemon shark, emperor penguin and parasitic wasps. Despite the title of the program, there isn't really much in-womb development: the kangaroo develops in its mother's pouch, the lemon shark initially lives off a yolk sac then becomes attached to it's mother via a placenta, the penguin embryo develops inside an egg kept warm on its father's feet.
And then there are the parasitic wasps. Wasp eggs are injected into a caterpillar, which provides a cozy protected space for the embryos to develop. Once they have matured, the larvae paralyze their host and bite their way out. Sound familiar? They were the inspiration for the "birth" scene in the 1979 movie Alien (The Director's Cut), which used John Hurt in the caterpillar role. *shudder*
Here's their video of the parasitic wasp larvae emerging from a caterpillar:
Tags:science fiction, parasitic wasp, Alien