Question Regarding Dawkins' The Blind Watchmaker

[CJ2116]

Hi everyone,

I'm currently reading Richard Dawkins' book The Blind Watchmaker and there is one part that had me really fascinated, but wasn't really explored in detail that much.

On page 249 he writes:

Duplication within the species isn't the only means by which the number of cooperating genes has increased in evolution. An even rarer, but still possibly very important occurrence, is the occasional incorporation of a gene from another species, even an extremely remote species. There are, for example, haemoglobins in the roots of plants of the pea family. They don't occur in any other plant families, and it seems almost certain that they somehow got into the pea family by cross infection from animals, viruses perhaps acting as intermediaries.

I know that some organisms (like anglerfish that use bio-luminescent bacteria, for example) can use other organisms in their own biochemistry, but I wasn't aware that a "cross infection", as he puts it, could occur.

Can anyone point me in the direction of some additional resources that explore this topic in detail? Preferably at the "pop science" level as my background is in math and physics, not biology!

Thanks!

 

[atyy]

I'm not sure what Dawkins had in mind, but searching for "horizontal gene transfer plants" on Google turned up http://www.ncbi.nlm.nih.gov/pubmed/...l+gene+transfer+on+plant+colonization+of+land (paper is free using the PMC link at the top right of the page). The introduction of the paper could provide some leads.

Arredondo-Peter and Escamilla point to a hypothesis by Appleby et al that Dawkins may not be right on this point, and that there may be hemoglobins in other other plants. Some more current work seems to be described in http://www.ncbi.nlm.nih.gov/pubmed/19704508 and http://www.ncbi.nlm.nih.gov/pubmed/23600702.

 

[CJ2116]

Excellent, thanks for the reply - knowing the name of what he's talking about should help narrow down the results!

 

[Salman2]

Here is another mention of the process...a host species maintains a complete copy of a parasite genome:

http://www.rochester.edu/news/show.php?id=2963

 

[LudusRex]

I find this topic very interesting as well. The idea of genes being transferred between species, known as horizontal gene transfer, has been studied extensively in recent years. It is a relatively rare occurrence, but it has been shown to play a significant role in evolution.

One example of horizontal gene transfer is the transfer of antibiotic resistance genes between bacteria. This has been a major concern in the medical field as it can lead to the spread of antibiotic resistance.

In terms of the specific example mentioned in the book, the transfer of haemoglobin genes from animals to plants is an interesting and rare occurrence. It is thought that this transfer may have occurred through viruses, which are known to be able to transfer genetic material between different species.

If you are interested in learning more about horizontal gene transfer, I recommend looking into the work of microbiologist Carl Woese and his research on the tree of life. He proposed the idea of a "web of life" rather than a tree, as horizontal gene transfer blurs the lines of traditional evolutionary relationships.

I also suggest reading articles or books by scientists such as Lynn Margulis and Eugene Koonin, who have studied and written extensively on horizontal gene transfer. These resources should provide a deeper understanding of this fascinating topic.