Week 8- Slime Mold Streets
Slime molds simple rules of behavior may lead to an efficient and adaptable
network of railways. Scientists have recreated an almost exact model of
Tokyo’s railway system using a mindless living organism .The yellow slime
mold Physarum polycephalum grows as a single cell that can be seen with
the naked eye. This slime mold can find numerous food sources in close
proximity and creating channels to those nutrients for distribution
throughout. The channel tunnels are efficient, beginning in an evenly
scattered pattern, then over time, refining the channels to minimize excess
channel distances. The most centrally located tunnels were the strongest
and most resilient. The heavy load bearing tubes become the most robust
and are optimized while the redundant tubes get pruned. Since tumor’s act
very similar, scientists hope to learn more about them. (Ref. 1)
Click on this nice short video link which shows the slime mold fanning out
with many skinny fan-like tubes and the refine itself eliminating the
unnecessary tubes and reinforcing the best, most efficient pathway to the
food sources.
It sends out “scout tubes” called tendrils in all directions to look for the
food. (Ref. 2) This is very similar to harvest ants. The more chemical
contacts the ant gets form the antennae of other ants, the greater number of
foragers are needed to go out and get the food, likewise, the more nutrients
or food contacts the slime mold recieves causes more flow and thicker
tunnels to that area. The whole will benefit because of what the localized
parts have accomplished.
And just like swarming colonies, these slime molds are self-organizing,
coming up with a very simple method that works. University of Japan
researchers have been developing new biologically inspired mathematical
models, with highly efficient algorithms for applications in computer
sciences. (Ref. 3) Toshiyuki Nakagaki states that slime molds have a high
ability of information processing that can be used in other networks like
mobile communications. (Ref. 4)
Another interesting application used by the slime molds is in the field of
health and medicine. Scientist believe that there are astunding similarities
between the slime molds pathways for food and the blood flowing pathways
to feed tumors. Scientists believe they can help find a way to prevent or kill
them. Biophysicists in Singapore and Germany believe that they can make a
mathematical model that can help doctors develop techniques to starve the
tumors of their blood supply. (Ref. 5)
I don’t believe that the railway system is true biomimicry especially since
the Tokyo railway system was built before the slime mold discovery. I also
think that land terrains around the world are quite different and engineers
“connecting the dots” can still do a great job. With that said, there are
applications that can be bioinspired using these organisms. Since the
largest tubes are formed where the most nutrients are found and flow,
scientists can develop a system to maximize transportation flow. An
experiment may possibly be done to find a efficient scheduling system for
trains. If more passengers are gathering at a paticular rail station, they
would get a bigger piece of oats. Then traffic controllers can create a
mathmatic model to schedule trains better in areas where the thickness of
the slime mold tubes are larger and less trains for areas where the tubes are
thinner. This idea can also help with internet bandwidth speed. Using
auxiliary pathways when the main one is clogging up would be a useful tool
since internet traffic is dynamic and always adjusting, like the mold tubes
which can also adjust and move to an area with a greater flow of nutrients.
Here is a longer good video link, where the slime mold solves a maze and
more. ****Go to the 1 hour and 3 minute 30 second mark of the
video*****
Citations:
Reference 1- http://www.wired.com/wiredscience/2010/01/slime-moldgrows-network-just-like-tokyo-rail-system/
Reference 2- http://www.treehugger.com/cars/mold-may-help-designfuture-transportation-routes.html
Reference 3 http://www.sciencedaily.com/releases/2010/01/100121141051.htm
Reference 4http://www.nytimes.com/2010/01/26/science/26obmold.html
Reference 5 - http://www.wired.com/wiredscience/2012/08/slime-moldscancer-growth/