The Mighty Ant-Lion

i-710d005c8660d36282911838843a792d-ClockWeb logo2.JPGFirst written on March 04, 2005 for Science And Politics, then reposted on February 27, 2006 on Circadiana, a post about a childrens' book and what I learned about it since.

When I was a kid I absolutely loved a book called "Il Ciondolino" by Ricardo Vamba - a book in two slim volumes for kids (how times change - try to publish a 200+ page book of dense text for children today!). I later found out that it was translated into English under the title The Prince And His Ants in 1910 (Luigi BERTELLI (M: 1858 or 1860 - 1920) (&ps: VAMBA) The Prince And His Ants [It-?]. Holt.(tr S F WOODRUFF) [1910] * Il Giornalino Di Gran Burrasca [It-?] (tr ?) [?] ) and was even The Nation's Book of the Week on June 2nd 1910.
i-98d530c97a4bffdd5c38341ec400ee15-a1 Ciondolino.jpg

["Vamba" is the pseudonym of Italian fantasist Luigi
Bertelli. The Prince and His Ants (1910) tells the tale of a boy who becomes an
ant, and a girl who becomes a butterfly. The English translation by one Miss
Woodruff was edited by Vernon Kellogg, an insect authority at Stanford
University. Ninety interior illustrations are scientifically accurate.]


This book is hard to find - don't even bother with Amazon - but my brother was persistent and after several weeks of patient searching he got a copy from Alibris and sent it to me. It is a story of a boy who wakes up one morning transformed into an ant. The book describes his travels and adventures in the world of the small. Of course, he meets a bunch of really cool creatures, like various wasps and bees and moths and honey-ants, etc. But the one I remember the most was the ant-lion.

The antlion is actually quite pretty, yet short-lived, as an adult. But it is the larva that is really cool:
i-97dfab6df3530d888cd13d39aafe1e8e-a2 Ant Lion.jpg
It digs a pit in the send and hides underneath the sand right under the bottom of the pit. When an ant, or some other insect comes by, it falls into the pit and has trouble climbing out of its steep walls again. The ant-lion lunges out of the sand (like a scence from "Tremors") and eats the poor bug:
i-d889b237f58e02381e5868ceb41b4f2d-a3 Ant Lion Funnel.jpg
Now the really cool part: the volume of the pit is bigger when the antlion is hungrier (or so they say at this marvelous website that I highly recommend you browse around). But, hungry or not, the ant-lion digs a bigger pit when the moon is full. Nobody has any idea why that would be so. Here is a photograph of a colony of ant-lions, each with its own little pit:
i-1c1295f141079af8c689ceeedf3dc74e-a4 Ant Lion Photo.jpg
But here is the coolest part of all. If you take ant-lions out of the field and put them in little sandboxes in the laboratory and isolate them from any cues about the outside world they will still dig bigger pits roughly every four weeks - they have an internal lunar rhythm:
i-d40f83db952823c6ebf5b345e3272e5f-a5 Ant Lion Pit Size.jpg
They have, somewhere in their brains, a lunar clock that tells them to dig larger pits whenever the moon is full even if they canot see the moon itself (e.g., on a dark cloudy night). If and when somebody figures out how this little brain works, I'll be sure to tell you all on my blog, but you may have to wait years for it - nobody is even thinking about studying it right now.

More like this

I'm not completely convinced. The real experiment is to raise generations of ant lions inside where light is controlled, to see if their clock can be put out of phase with the moon. There may be other things going on beside internal clocks.

What would be the reason to sync up with the Moon's phases? Is there a hypothesis or theory on it? It's easy to presume that since some insects are more active at night of a full Moon that it can take advantage of.

I haven't seen antlion pits or the adults in some years, but indeed they are awesome creatures. I've never actually been able to dig out the larva.

AlexL, #2 - It is possible to dig them out but the easiest, or at least the most interesting and fun, way of catching them is to go fishing.

This is done by using a bit of grass or a pine needle. You find a likely ant lion pit. Lay down on the ground and then gently poke your 'pole' down the hole attempting to simulate the motion and vibrations of an insect caught in the funnel. Too much action and you scare the ant lion and it won't bit. Too little and it isn't stimulated enough to attack. When you get it just right the ant lion will clamp its jaws around your pine needle. Then it is just a matter of worrying the ant lion out of its hole.

This might take some finesse. Sometimes not. Sometimes you can just pull and the any lion will hold on even as it is hauled out of the hole. Ending up suspended by your blade of grass. Other times you have to work it slow. Pulling just enough to draw the ant lion out a bit without scaring it enough to let go. Pulling a bit and backing down a bit, like you might play a fish.

This is a fun sport for kids. Nature study, an exersise in patience and finesse, and low cost fun.

Even adults have been known to play the game. Often making the competition sweeter by betting on the outcome. First to get three ant lions is one way to go.

And here I was thinking that everybody knew about this sort of thing.

Ant-lions are awesome!
I remember wasting hours under-the-house* as a kid trying to tease them out - either with the grass blade trick above by Art, or with live bait (I hadn't done my unergrad ethics courses yet).

If you try to dig an ant-lion out without baiting it first you are doomed to failure, I assume they can sense the soil disturbance and burrow deeper.

*Google Queenslander architecture