There may be no bug creepier than a tick.
These sesame-seed-sized parasites crawl slowly and silently up our bodies, surround their mouth-parts in our skin, and then casually slurp their fill of our blood until their bodies expand like tiny water balloons.
So as you carefully pluck a tick from your skin, you may undoubtedly wonder: what purpose could they possibly serve? What good are ticks, exactly?
This episode originally aired on May 3, 2016.