Why bacteria run Linux while eukaryotes run Windows?
Sep 18, 2013
3:30PM to 4:30PM
Date(s) - 18/09/2013
3:30 pm - 4:30 pm
Title: Why bacteria run Linux while eukaryotes run Windows?
Speaker: Dr. Sergei Maslov
Institute: Biology Department, Brookhaven National Laboratory
Location: ABB 102
Bacterial genomes and large-scale computer software projects share a number of similarities. They both consist of a large number of components (genes or software packages) connected via a network of mutual dependencies. Components can be easily added or removed from individual systems, and their occurrence frequencies vary over many orders of magnitude. We studied  the occurrence frequencies of genes in genomes of ∼500 bacterial species and compared it to frequencies of installation of software packages on over 2 million Linux computers. We found that in both cases frequency distributions have similar U-shaped functional form with a powerlaw scaling for small frequencies and an additional peak at the tail of the distribution corresponding to nearly universal components. I will derive a general mathematical expression for this distribution valid for any modular complex system. This derivation is limited to open source systems such as Linux/bacteria characterized by reuse and common sharing of previously developed components. In addition to genomes and large software projects we found similar properties in networks of citations between scientific publications, dependencies between mathematical theorems, and food webs in ecosystems.