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WonderBiological design fact

The yellow slime mould Physarum polycephalum, a single-celled organism with no brain, can grow a network of tubes between scattered pieces of food that balances short routes, backup links and low cost, much as engineers try to do.

Science study, 2010

BiologyScienceDesignTechnology

The story behind the card

Despite its name, a slime mould is not a fungus: Physarum lives as one giant cell with many nuclei that creeps over damp logs, feeding on bacteria and fungal spores. In a 2010 study in the journal Science, a team led by Atsushi Tero of Hokkaido University placed oat flakes in the pattern of 36 cities around Tokyo and set the slime mould on the spot marking Tokyo. Bright light, which it avoids, stood in for mountains and sea. Within about a day it had linked the oats with a network that closely matched the real Tokyo rail system in efficiency, cost and resistance to breaks. The team then turned the organism's simple local rules into a mathematical model for designing networks.

Türkçe oku
Sarı renkli cıvık mantar Physarum polycephalum, beyni olmayan tek hücreli bir canlıdır. Yine de dağınık besin parçaları arasında, mühendislerin de yapmaya çalıştığı gibi kısa yolları, yedek bağlantıları ve düşük maliyeti dengeleyen bir tüp ağı örebilir.
Science dergisi, 2010

Adına rağmen cıvık mantar bir mantar değildir: Physarum, çok sayıda çekirdek taşıyan tek ve dev bir hücre olarak yaşar; nemli kütüklerin üzerinde sürünerek bakteri ve mantar sporlarıyla beslenir. Science dergisinde 2010'da yayımlanan bir çalışmada, Hokkaido Üniversitesi'nden Atsushi Tero'nun yönettiği ekip, yulaf tanelerini Tokyo çevresindeki 36 kentin konumlarına göre dizdi ve cıvık mantarı Tokyo'yu gösteren noktaya koydu. Dağları ve denizi, canlının kaçındığı parlak ışıkla temsil ettiler. Cıvık mantar bir gün kadar içinde yulafları birbirine bağlayan bir ağ kurdu; bu ağ verimlilik, maliyet ve kopmalara dayanıklılık bakımından Tokyo'nun gerçek demiryolu ağına çok benziyordu. Ekip daha sonra canlının basit yerel kurallarını, ağ tasarımında kullanılabilecek bir matematik modele dönüştürdü.

Sources and further reading

Background reading: Physarum polycephalum
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