The phenomenom of spread

Here’s an adapted extract from part of my original thesis. I removed this in the end, since it wasn’t directly relevant to the spread of invasive species and the thesis was already too long. This text does however link several different fields that are interested in the spread of something, and I find connections across scientific fields interesting because these days they are rife with fertile research directions.

The seminal works of R. H. Fisher (1937) described the propagation and diffusion of advantageous alleles in a population, and a lot of current theory on spread and dispersal has it’s root in population genetics.

Recent work on the spread of humans, with heredity between individuals, have indicated that certain mutations are either maintained with low frequencies at their origin or are propagated along wave fronts. If these mutations are tracked then it is possible to establish their origin (Ibrahim, 2004).

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Calling Matlab people

I wouldn’t normally post a job position on my personal blog, but my supervisor is having trouble finding someone with Matlab skillz.

Basically someone in the university has got some research funding to do some grid computer, and my supervisor wants to get a whole lot of Self Organising Maps and Multilayer Perceptrons (both a type of Artificial Neural Network, ANN) running on a computing grid. All the code for the ANNs etc is there, from my understanding it just needs to be adapted to run in parallel across the computing grid.

Shoot me an email if you are in chch looking for some temporary work ( ).

Fucked up hard drive

So I needed a 300G hard drive to store results from my research, and I asked for an external one so that I could take the results home with me if I wanted to work at home. ITS got me one (after trying to convince to get an internal one, claiming they are more of a risk for data loss) but they got a really crappy no name brand USB enclosure. It generally works okay, but if I start doing heavy amounts of data transfer it dies. And then I can’t actually access the hard drive properly until I turn it on and off again (IT crowd anyone?).

After I switch it back on and try and mount it I get:

mount: wrong fs type, bad option, bad superblock on /dev/sdb1,
       missing codepage or other error

How does one fix this? Well…

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