Science and Creationism 17. Speciation © Colin Frayn,

© Colin Frayn, Speciation vs. Micro Evolution Micro evolution = change in allele frequency –E.g. disease resistance –E.g. moths in industrial England Darker moths hid against sooty buildings, light moths got eaten When buildings were cleaned, the trend reversed Speciation –This happens far more slowly Usually requires separation of a population –It has been seen in many species Several plants Bacteria & viruses To list a few specifically: Culex molestus, Primula kewensis, Oenothera gigas, Gaelopsis tetrahit, Madia citrigracilis, Mimulus guttatus, Drosophila paulistorum, Rhagoletis pomonella, Eurosta solidaginis, Nereis acuminata, Chlorella vulgaris, Woodsia abbeae, etc…

© Colin Frayn, Micro-Evolution Did the peppered moth story ever happen? –Yes, it did… –…though who cares? Micro-evolution like this is undenied and undeniable To deny this effect, you need to deny at least one of: 1.Certain physical traits are genetic 2.Genetic information is passed on through reproduction 3.Certain physical traits can affect an individual’s survival chances. 4.Environmental changes can occur which alter the fitness landscape. Denial of 1,2 or 3 is impossible 4 is almost certainly true, but it’s irrelevant to biology

Allopatric vs. Sympatric Speciation Genetic isolation is required for speciation Allopatric Speciation –Geographically separated Continental drift Mountains, rivers etc. Sympatric Speciation –Sharing a geographical location –Occupying different niches Colouring Food preferences © Colin Frayn,

© Colin Frayn, Gaining new genetic information Q: Does evolution break some mystical law forbidding ‘increase in information’? A: Not at all! (see next slide for theory) Q: How can we create ‘information’ from nowhere? A: Mutation, insertion, replication. –All of which are well documented and happen all the time Remember – all creatures are made from their genetic blueprint –‘Information’ is just what’s in the DNA –If we can create new DNA, then that’s new ‘information’ –The differences between all animals are just DNA differences –We can generate any DNA differences using known muations

© Colin Frayn, Conservation of Information Original law (Medawar, 1984) –Stated that Kolmogorov information could not increase in a closed system No simple recipe can generate an item more complex than the recipe itself, for this particular mathematical definition of ‘simple’ and ‘complex’ Non-scientific version (Dembski, 1998) –Dembski completely misunderstands complexity theory –He confuses Shannon and Kolmogorov complexity –His resultant theory is worthless “Complex Specified Information” –A term invented by Dembski –It is never rigorously defined Dembski’s law is obviously false –Genetic ‘information’ is created all the time by evolutionary processes –(See the previous slide)

© Colin Frayn, Beneficial Mutations Most mutations are negative –So how can progress occur? Actually, most mutations are neutral –See ‘Neutral Evolution’ theory of Kimura (d. 1994) Negative mutations are rejected –Most are rejected immediately Positive mutations survive and are passed on Studies of bacteria show how beneficial mutations accumulate –See work of Richard Lenski with the bacterium E. coli –Bacteria evolved the ability to consume citrate

© Colin Frayn, Phylogenetic trees These are not based on guesswork! They can be generated using sophisticated clustering algorithms: –Compare similarity between all individuals –Optimise a tree to minimise distance between similar individuals –You can use any property for ‘similarity’, e.g. any gene or sequence of genes –The trees usually agree very well Even when they are created from a totally different source Which implies that there is a real underlying relationship

© Colin Frayn, Humans