Wednesday, June 11, 2008

The Secret Lives of Herbs

An interesting article in the NY Times science section this week on recent findings that a particular species of plant can recognize its relatives.

Research by a Canadian group (Ontarian, to be exact), found that the Great Lakes sea rocket (the perfect name for a beach weed), aka Cakile edentula, appears to be able to distinguish between plants that are related to it, and those that are not (published in Biology letters - and if anyone can tell me why this was buried in this journal, I will be forever grateful).

The bottom line here is that plants do not have consciousness (which should go without saying...).  But through some yet unknown mechanism they are able to sense when they are in a pot with siblings, and they decrease their root allocation in this situation compared to when they share a pot with strangers (i.e. non-related plants). Presumably, the plants can tell through some chemical signal when they are surrounded by other plants, allocating to their roots in order to out-compete them.  Somehow the signal is different when the surrounding plants are siblings, resulting in decreased allocation (and fitness, importantly).  The difference in allocation seems pretty significant, and the error bars are not enormous. The question remains - what signals are given off by sibling plants telling them to decrease allocation (maybe whoever answers that will have themselves a Science paper).  

The world is a fascinating place on it's own, so please do not try to explain this by invoking psychic ability of plants!



snail.sfury said...

Hey, thanks, I went and read the original paper, cool. I didn't figure plants would be able to 'care about' kin recognition. Am very curious as to the actual mechanism. (You'd think there could be something of an immune system like affair, with a plant matching factors of another plant to its own... but do plants actively send out signal chemicals ("This is me!") or do they have to probe for them ("Who are you?")? The authors cite another paper which claims that plants can even distinguish between self and non-self if non-self is genetically identical... so maybe they make a distinction on the basis of factors produced during development too...? go figure.)

As to the question why it was 'buried' in "Biology Letters"... maybe (a) it is not THAT big a discovery, since the authors cite a bunch of older papers with similar content, and (b) I don't know how well-known this journal is in biology circles (seems to be a short-letter spinoff of Proc Roy Soc B) but the fact that many of its papers are freely accessible online certainly makes it 'un-buried' enough for the NYTimes and then you to pick up on it. :)

DS said...

Good point. I'm no plant biologist, so it's hard for me to say if the findings are all that novel, or even how obscure the journal is (I am a biologist, and I've never even heard of it before). I think the main reason is that there is a huge difference between discovering a phenomenon and describing it. Figuring out how this happens would be big news.

As you say though, it doesn't matter much because good science gets read no matter where it gets published. The stuff that gets into the best journals just gets read a little quicker.

Thanks for reading!