The Science Behind The X-Files:

Ice

• In this episode, Mulder and Scully travel to an arctic research station, where contact was lost with a crew of scientists studying ice cores. Similar to tree cores (see DARKNESS FALLS), ice cores are cylindrical samples of multi-layered ice, taken by drilling straight down, that show the chemical sediments that have frozen in subzero regions (e.g., mountaintops, arctic/antarctic landmasses). Scientists can use ice cores to find out about what the earth was like a long time ago through paleoclimatology, the study of earth's climate at distant times in Earth's past.
  
  For more information on ice coring and paleoclimatology, check out the Ohio State University Byrd Polar Research Center's page on ice coring at http://www-bprc.mps.ohio-state.edu/Icecore/.

• The two agents and their investigatory team discover that some of the ice cores contain a mysterious worm, sustained in an environment of ammonium hydroxide that would kill normal terrestrial life. Think that's impossible? A team of researchers from Penn State University recently discovered a new species of worm living in the icy depths of the Gulf of Mexico, feeding off of frozen methane deposits. Amazing!
  
  To learn about the work of Chief Scientist Charles Fischer and the ice worms that his research team found in the gulf, check out their home page at http://www.bio.psu.edu/cold_seeps/.

• It appears to Scully, Mulder, and the rest of the investigatory team, that the scientists at the arctic station succumbed to a parasitic worm (see THE HOST) that latched itself onto the hypothalamus and accelerated the body's production of acetylcholine. The hypothalamus is a small part of the brain that controls many autonomic body functions. Acetylcholine, like serotonin (see SLEEPLESS), is a neurotransmitter, a chemical used in the brain to pass electrical signals from one neuron to another. Acetylcholine, as Dr. Hodge explains in the episode, has also been linked to the control of aggressive behavior.
  
  To find out more about the hypothalamus, read the Encarta Encyclopedia entry on that part of the brain.

• One of the side effects of the worm infestation on the show is underarm "buboes." Buboes were the telltale marks of bubonic plague--swollen black bumps on the skin caused by a severe infection of the lymphatic system. The black coloration in the spots is due to blood that dries just under the skin, leaving a bubbly mark that looks like a black blood-blister. I don't think the episode explained why the parasite inflamed its victim's lymph nodes, but I would assume that any kind of creature squirming around and causing havoc in your system might possibly give your body cause to react in this manner. (It is science-fiction, after all.)
  
  To find out a little more about bubonic plague, read a primer from the Entomology Department of Virginia Tech at http://www.ento.vt.edu/IHS/plague.html.
  To learn more about the human body's lymphatic system, go to the UIUC VAT (University of Illinois at Urbana-Champaign Virtual Anatomy Textbook) page on the lymphatic system at http://www.acm.uiuc.edu/sigbio/project/updated-lymphatic/lymph1.html.