

The Physics of Ants [video] - dylandrop
http://www.nytimes.com/video/science/100000002605952/sciencetake-the-physics-of-ants.html

======
acadien
Super interesting! As a material scientist this is really interesting to me,
and I'm surprised I've never seen an article on the topic. I am aware that
there is a _lot_ of physics that we don't understand when it comes to macro-
molecular systems, let alone _living_ macro systems. So I'm sure there's
plenty to of new ideas to explore here.

On a side note I am really frustrated with the NYTimes video service, I have
never had one of their videos play through without freezing!

~~~
dylandrop
When I posted this I also had a thought that despite taking standard metrics
of viscosity, elasticity, etc. it seems like it would be very difficult to
model something like a glob of ants since each ant is obviously a lot more
complex than a molecule. Perhaps, as a material scientist, you could speak to
the difficulty of doing this?

~~~
acadien
This is off the top of my head and with no knowledge of the progress of the
work done already on the topic... so please take this with a grain of salt!

I would be inclined to try to develop a model of the system and see if I could
reproduce the measured viscosity and elastic properties from a simulation.
From there you can do things like free energy calculations and figure out
which ant-phase is the most stable under which conditions.

You're right that in reality each ant is much much more complex than a
molecule. But since we're scientists we get to approximate (hooray for
spherical cows).

To build the model you just treat each ant as an elastic ellipsoid with
directional bonding properties. You start off by ignoring the legs and
ignoring or greatly simplifying the motion of each individual ant. The first
hurdle would be to figure out an ant's bonding properties as this is crucial
to the stability of the total structure's properties. Play around with that
until your simulation starts reproducing reality; add complexity as necessary;
iterate and repeat.

As far as experimental measurements, I couldn't even guess what to do next
without reading some of their publications.

------
hodgesmr
What is this? Physics for ants?

------
tectonic
I had a lot of fun writing an ant foraging simulation a year ago:

[http://andrewcantino.com/?open=showAnts](http://andrewcantino.com/?open=showAnts)

Ants are super cool!

~~~
waldir
Is their sense of orientation really that great? In your simulation, when a
wandering ant finds food, it heads right back to the anthill in a straight
line. All I know from this is from reading about Feynman's experiments, but
what he says seems to be more realistic:

 _One question that I wondered about was why the ant trails look so straight
and nice. The ants look as if they know what they 're doing, as if they have a
good sense of geometry. Yet the experiments that I did to try to demonstrate
their sense of geom­etry didn't work. Many years later, when I was at Caltech
… some ants came out around the bath­tub… I put some sugar on the other end of
the bathtub… The moment the ant found the sugar, I picked up a colored pencil
… and behind where the ant went I drew a line so I could tell where his trail
was. The ant wandered a little bit wrong to get back to the hole, so the line
was quite wiggly, unlike a typical ant trail._

 _When the next ant to find the sugar began to go back, I marked his trail
with another color… he followed the first ant 's return trail back, rather
than his own incoming trail. (My theory is that when an ant has found some
food, he leaves a much stronger trail than when he's just wandering around.)
This second ant was in a great hurry and followed, pretty much, the original
trail. But because he was going so fast he would go straight out, as if he
were coasting, when the trail was wiggly. Often, as the ant was "coasting," he
would find the trail again. Already it was apparent that the second ant's
return was slightly straighter. With successive ants the same "improvement" of
the trail by hurriedly and carelessly "following" it occurred. I followed
eight or ten ants with my pencil until their trails became a neat line right
along the bathtub._

------
pablovidal85
I don't get why this is an interesting study. Can somebody explain me?

~~~
dylandrop
Look to the end of the video -- these sorts of studies could tell us more
about making interesting new materials or perhaps small robots that can behave
similarly when clumped together.

------
disputin
Fantastic! After all these years of watching all sorts of interesting ant
behaviour, that's a new perspective.

