Abstract
Background
Both competitive and facilitative interactions between species play a fundamental role in shaping natural communities. A recent study showed that competitive interactions between plants can be mediated by some alternative signalling channel, extending beyond those channels studied so far (i.e. chemicals, contact and light). Here, we tested whether such alternative pathway also enables facilitative interactions between neighbouring plant species. Specifically, we examined whether the presence of a ‘good’ neighbouring plant like basil positively influenced the germination of chilli seeds when all known signals were blocked. For this purpose, we used a custom-designed experimental set-up that prevented above- and below-ground contact and blocked chemical and light-mediated signals normally exchange by plants.
Results
We found that seed germination was positively enhanced by the presence of a ‘good’ neighbour, even when the known signalling modalities were blocked, indicating that light, touch or chemical signals may not be indispensible for different plant species to sense each other’s presence.
Conclusions
We propose that this alternative signalling modality operates as a general indicator of the presence of heterospecifics, enabling seeds to detect and identify a neighbour prior to engaging in a more finely-tuned, but potentially more costly, response.
Tag Archives: science
Had any postprandial somnolence recently?
I somehow have a fascinations for scientific explanations to things we
anyway know intuitively. I would love to have a book just filled of
these.
Mad Science
A friend of mine, with an overly sceptical view of natural sciences, sent me this article on how "science" is often misused to perpetuate and "proove" our held beliefs, norms and associated behaviours.
The article lists a number of amusing (and scary) anecdotes about misused science, and comes up with the following five items to watch out for:
1 Do the Conclusions Fit a Little Too Well With Cultural Stereotypes?
2 Does the Study Agree With the Headline?
3 Can You Spot the Double Standard for men and women!
4 Is There Another Conclusion That Would be Just as Valid?
5 Is the Study Even Science?
Why we kiss
Kissing was developed ‘to spread germs’
It isn’t the most romantic theory, but scientists believe kissing was developed to spread germs which build up immunity to illness.
The bug is found in saliva and normally causes no problems. But it can be extremely dangerous if caught while pregnant and can kill unborn babies or cause birth defects.
Writing in the journal Medical Hypotheses, researcher Dr Colin Hendrie from the University of Leeds, said: “Female inoculation with a specific male’s cytomegalovirus is most efficiently achieved through mouth-to-mouth contact and saliva exchange, particularly where the flow of saliva is from the male to the typically shorter female.”
Kissing the same person for about six months provides the best protection, he added.
As the relationships progresses and the kisses become more passionate, the woman’s immunity builds up, cutting her odds of becoming ill.
By the time she becomes pregnant, the odds of her unborn baby becoming infected are much lower.
Previously scientists have claimed that kissing acts as a form of evolutionary quality control, with saliva holding clues to fertility, health and genes.
But the psychologists from Leeds and the University of Central Lancashire said these things can be judged without getting quite so intimate.
Dr Hendrie said: “Information concerning body tone, smell, reproductive condition, disease state and, of course, personal physical and oral hygiene can all be gained solely from close physical proximity.
“The small amount of additional information from kissing is an unlikely pressure for its development.”
To me, explaining things makes them more beautiful. Think of all the effort, iterations and different attempts to solve this problem that must have been tried in evolution’s path. In the end, it ended up with such a simple, beautiful activity.
Photo by by Michael Sarver
Craig Venter unveils “synthetic life”
We are able to make synthetic cells – eventually creating computer programs that allow us to create new life….