A message to Nature Notes listeners: if the movie Alien, the 1979 sci-fi classic, gave you nightmares, this isn't the episode for you.

“There are,” as Shakespeare reminds us, “more things in heaven and earth than are dreamt of in your philosophy,” and reality bears that out: the natural world doesn't lack for the extreme, the bizarre.

When it comes to the gross-out department, few phenomena can compete with parasitoid wasps. Ranging from a fraction of a millimeter to 2 inches in length, these insects provide for their young in a lurid way: by laying their eggs on, or within, the bodies of other creatures.

Dr. David Althoff, of Syracuse University, studies parasitoid wasps.... Hosted by for KRTS