Random Mutation and Evolutionary Change

A few months ago someone made a comment that he had difficulty reconciling evolution's reliance on Random Mutation with what he saw as Ordered Change over time as the environment changes.  This set me thinking, would it be possible to simulate such random changes and couple them with a changing environment to see what might happen.

This post gives a brief flavour of what I managed to achieve - taking a VERY simplified organism, in a VERY simple world.  Throw in a bit of programming, and out comes a simple Windows program which allows the user to play with the numbers and see the results.  The image on the right is one such output - a single organism (at the top) living in an environmental niche (the green stripe) reproduces and multiplies over successive generations (the grey/black stripes down the image).  It soon populates the whole width of the niche, though individuals tend to die out or fail to reproduce at the extremes of the niche.  Then the environment changes - shifting from green to orange - and the random mutations over the generations allow the population to 'adapt' to the changes.  BUT then the environment shifts more quickly - from orange back to green and over to blue.  The rate of  'evolution' within the population can't keep pace, and the entire population dies out.  Woops! Extinction!

A more complete explanation of the model can be found in this PDF (590kb)  which also explains how to use the software, which is available in this ZIP file (2.7mb).  As I say in the notes - Go Play!

LIDAR imaging of the Hilltop Enclosure and Field System in Ecclesall Woods, Sheffield

 An earlier post (here) outlined some of my 'playing' with LIDAR data from the data.gov.uk web-site, this post outlines some of my results.

The main area I looked at was the high ground to the west of the 'bird sanctuary' centered at about  SK317822.  This area had been investigated by Archaeological Survey and Evaluation Ltd. (ASE Ltd.) in 2002 and 2006 on behalf of the Friends of Ecclesall Woods (FEW).  Their reports (and others on Q-pits) can be found on the FEW web-site (www.friendsofecclesallwoods.org.uk) - I hope they will forgive me for using their results.

Playing with LIDAR data for Ecclesall Woods, Sheffield

I decided that it was about time I resurrected my Miscellany blog after a two year break, and I thought I would start with a bit of 'playing' that I have been doing over the last few days.

LIDAR Surface Model of the SMEE site at Ecclesall Woods

John Hunter, a fellow 'researcher' who is far more knowledgeable and hard working than I am, recently mentioned that the Environment Agency has placed LIDAR data for almost the whole country on the data.gov.uk web-site - the data for the 10km square around Sheffield can be found at www.geostore.com/environment-agency/survey.html#/survey?grid=SK28 .  This coincided with a walk around Ecclesall Woods here in sunny Sheffield, and I wondered whether the Q-pits and other structures that I knew existed in the woods might be visible on the LIDAR data.  So that meant it was play-time!

Sure enough, lots of structures were visible, and this posting outlines the process I followed - a separate post (here) will look at what I found.