S cience is amazing, but it can involve doing some pretty weird stuff. Just in time for Halloween, here are seven science experiments that are creepy, scary, or just plain gross! 1. Scientist lets insect live inside her The sand flea Tunga penetrans , here in a scanning electron microscope several days after penetrating the skin. Eye of Science/Science Source The sand flea, also known as chigger flea, is pretty gross. It burrows permanently into the skin of a warm-blooded host—like a human—where it swells, defecates, and produces eggs, before dying 4-6 weeks later, still embedded in the skin. We know a lot about them, but until now, their sex lives have been shrouded in mystery. Not anymore: A researcher in Madagascar was so interested in sand flea development that she let one of the bugs live inside her foot for 2 months. Her intimate observations paid off: She figured out that the parasites most likely have sex when the females are already in...