4 ms·

Venus flytraps 'able to count' in order to avoid false alarms, study finds

26 points by prawn 11y ago

chriskanan 11y ago
I haven't read the paper, but I assume the novelty here is the discovery of what happens when more than two of the hairs are triggered. The BBC Life series with David Attenborough talked about the counting/triggering mechanism years ago: https://www.youtube.com/watch?v=O7eQKSf0LmY https://www.youtube.com/watch?v=O7eQKSf0LmY
- gypsy_boots 11y ago
  Ya I immediately thought of the same Life segment. Is there something new in this discovery that I'm not seeing? Maybe the fact that they can also tell how big the prey is and add digestive enzymes accordingly?
  - oneeyedpigeon 11y ago
    Yes, that process you refer to apparently kicks in after 5 triggers which, I think, is a much more impressive feat of genuine counting. I'm now intrigued by its memory capacity and how that works.
    - anotheryou 11y ago
      A simple threshold seems easy to me. You just fire some messenger and if the concentration is high enough (N counts of messenger emitting) it reacts. Something binds or disassembles the messenger so the system resets after some time. The details would still be interesting of course.
tantalor 11y ago
The publication: http://www.cell.com/current-biology/pdf/S0960-9822(15)01501-8.pdf http://www.cell.com/current-biology/pdf/S0960-9822(15)01501-... Relevant snippet: We found that by counting and integrating the mechano-electric signals elicited by the trapped prey, Dionaea muscipula triggers biosynthesis of the touch hormone jasmonate, secretion of lytic enzymes, and channel-mediated uptake of prey nutrient-associated sodium loads.
collyw 11y ago
This isn't new. I studied biology at Glasgow University in 1992 and the botany lecturer told us about this then. One tap, two taps didn't trigger it to close, but three would. Along with a number of other examples of unexpected things that plants could do - this was his example of plants counting.
- dekhn 11y ago
  they're discussing the later phase after digestion has started.
mortdeus 11y ago
Yep. My flytrap won't trigger its petals until you poke it twice with a toothpick in the same general area. I think it does this for numerous reasons. 1. If the petals close and they don't actually capture anything, they take hours to open back up. 2. If they do close on something, (for example a fly or a spider I happen to come across) they will stay closed for days digesting whatever is trapped inside. The traps themselves don't actually survive this process. They wilt away and new petals grow to replace the old after a month or so. Speaking strictly from a natural selection point of view it make sense that a plant that has evolved to derive it's nutrients from carnivorism really has no chance at surviving if something as simple as a leaf, a seed, the wind, or any other poor nutrient provider could trigger it to close on said object (or not on said object). Either way, a plant that is in such need of nutrients can't really optimally survive if it closes at every opportunity it might have food in it's trap to catch. Natural selection seems to suggest that a venus flytrap that is more precarious about when to trigger it's trap is the far more optimal survivalist when it comes to these plants. I should also point out that calling them a flytrap is kinda lame considering their trap mechanism is not really all that fast enough to trap most flies. Atleast not in my observations. Although I have discovered that they get lucky from time to time, their trap mechanism is also apparently evolutionarily optimized to avoid most bugs that just land, chill for a minute, and fly away. Bugs they wouldn't likely catch. They would rather wait for a caterpillar, spider, beetle, etc to cross their path. My pitcher plant is the real fly catcher. It uses the old fashioned, "oh hey thats a nice smelling hole. I wonder what yummy things are down there for me and my maggot babies to eat. Dooo da doo da... eh... feets sticks to pitcher plant's trap oh no... AHHH! HELP! SOMEBODY HALP MEEEE!... HELLO?! Isn't there anybody out there!? ,,, ohhhh pooo. Well at least it still smells wonderful down here." technique.

26 points by prawn 11y ago

I haven't read the paper, but I assume the novelty here is the discovery of what happens when more than two of the hairs are triggered. The BBC Life series with David Attenborough talked about the counting/triggering mechanism years ago: https://www.youtube.com/watch?v=O7eQKSf0LmY https://www.youtube.com/watch?v=O7eQKSf0LmY

gypsy_boots 11y ago
Ya I immediately thought of the same Life segment. Is there something new in this discovery that I'm not seeing? Maybe the fact that they can also tell how big the prey is and add digestive enzymes accordingly?
- oneeyedpigeon 11y ago
  Yes, that process you refer to apparently kicks in after 5 triggers which, I think, is a much more impressive feat of genuine counting. I'm now intrigued by its memory capacity and how that works.
  - anotheryou 11y ago
    A simple threshold seems easy to me. You just fire some messenger and if the concentration is high enough (N counts of messenger emitting) it reacts. Something binds or disassembles the messenger so the system resets after some time. The details would still be interesting of course.

tantalor 11y ago

The publication: http://www.cell.com/current-biology/pdf/S0960-9822(15)01501-8.pdf http://www.cell.com/current-biology/pdf/S0960-9822(15)01501-... Relevant snippet: We found that by counting and integrating the mechano-electric signals elicited by the trapped prey, Dionaea muscipula triggers biosynthesis of the touch hormone jasmonate, secretion of lytic enzymes, and channel-mediated uptake of prey nutrient-associated sodium loads.

collyw 11y ago

This isn't new. I studied biology at Glasgow University in 1992 and the botany lecturer told us about this then. One tap, two taps didn't trigger it to close, but three would. Along with a number of other examples of unexpected things that plants could do - this was his example of plants counting.

dekhn 11y ago
they're discussing the later phase after digestion has started.

mortdeus 11y ago

Yep. My flytrap won't trigger its petals until you poke it twice with a toothpick in the same general area. I think it does this for numerous reasons. 1. If the petals close and they don't actually capture anything, they take hours to open back up. 2. If they do close on something, (for example a fly or a spider I happen to come across) they will stay closed for days digesting whatever is trapped inside. The traps themselves don't actually survive this process. They wilt away and new petals grow to replace the old after a month or so. Speaking strictly from a natural selection point of view it make sense that a plant that has evolved to derive it's nutrients from carnivorism really has no chance at surviving if something as simple as a leaf, a seed, the wind, or any other poor nutrient provider could trigger it to close on said object (or not on said object). Either way, a plant that is in such need of nutrients can't really optimally survive if it closes at every opportunity it might have food in it's trap to catch. Natural selection seems to suggest that a venus flytrap that is more precarious about when to trigger it's trap is the far more optimal survivalist when it comes to these plants. I should also point out that calling them a flytrap is kinda lame considering their trap mechanism is not really all that fast enough to trap most flies. Atleast not in my observations. Although I have discovered that they get lucky from time to time, their trap mechanism is also apparently evolutionarily optimized to avoid most bugs that just land, chill for a minute, and fly away. Bugs they wouldn't likely catch. They would rather wait for a caterpillar, spider, beetle, etc to cross their path. My pitcher plant is the real fly catcher. It uses the old fashioned, "oh hey thats a nice smelling hole. I wonder what yummy things are down there for me and my maggot babies to eat. Dooo da doo da... eh... feets sticks to pitcher plant's trap oh no... AHHH! HELP! SOMEBODY HALP MEEEE!... HELLO?! Isn't there anybody out there!? ,,, ohhhh pooo. Well at least it still smells wonderful down here." technique.