She's a stout little beetle, with clubbed antennae and a rounded butt.
About the size of a mouse dropping, the mountain pine beetle has powerful jaws to chew her way into a pine tree to the soft and, to the beetle's taste, delicious layer just below the bark.
If she succeeds — and it's always the female that leads the charge —she uses hormones to signal other beetles to join her. Thousands respond. Living outside trees for just two weeks, the beetles dig deep into the bark of this and nearby trees, eating and laying eggs. In a year, the tree needles are turning rusty red, and they're practically dead.