Warning; My wife says, "This could be your grossest post - a worm coming out of an acorn!"
Have you ever seen the acorn insects that make the neat little holes in acorns? Who makes these holes?
Scroll down to see a series of pictures of an acorn weevil grub as it squeezed its fat self out through a hole in an acorn.
Notice how the grub crawls... it uses its head to lift itself, contracts its body, then drops and stretches.
This photo shows a split acorn with an acorn weevil larva that was still inside when I cut open the acorn. Also visible is lots of frass, a bit of acorn nut meat, and perhaps some tiny, dipterous larvae.
Anyway, how does that fat acorn weevil grub manage to exit the acorn through such a small hole?
By the way, these holes make convenient entrances and exits for various other insects. See my next post about these acorn holes that are sealed by acorn moth caterpillars.