By the way, kudos for having the patience to run a 21 year experiment.

But they did carry out experiments that showed that in the “evolved” line recombination with the ancestor was inhibited and thus demonstrated “incipient speciation”

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=10377417&query_hl=5&itool=pubmed_DocSum

Of course, Lenski isn’t claiming this is speciation at all, but nevertheless it’s a demonstration of a new trait evolving when previously there wasn’t one.

This is now an “old” paper, earlier this month they published new work where they sequenced the genome of the different lines and also ancestral ones to figure out what genetic changes occurred.

http://www.scientificamerican.com/blog/post.cfm?id=evolution-details-revealed-through-2009-10-18

(Don’t have a link to the paper from Nature unfortunately and I haven’t read it yet myself.)

Since there turned out to be one strain that evolved Cit+ness reproducibly , and others did not – this means that there were already on some hidden(to us) biochemical or molecular level, two distinct species – one that had the potential to evolve Cit+ness and the other not.

In this light, the experiment does not show speciation, but merely the fact that variation can occur – which is not exactly news.

In any case, for bacteria and many other simple asexually reproducing organisms the concept of “species” is a not discrete, but a continuum. The test for speciation in the lab would be variation that leads to reproductive isolation , and thus splitting of a single population into two distinct populations with no chance of creating a hybrid progeny.

[WORDPRESS HASHCASH] The poster sent us ‘0 which is not a hashcash value.

You guys should blog your thoughts on it.

Good blogging!

Interesting read..