> On the VFT thread, is it true(got the info from Carnivorous Plants by
> Marcel Lecoufle) that after a VFT leaf eats 4 insects or a quantity "X" of
> 4, that the leaf will blacken and shrivel up?
Observation certainly suggests that this does occur, though not
exactly every 4 meals.
A few idle thoughts on the matter:
It would seem logical that, since the tightening of the trap is
caused by the rapid growth of cells along the outside of the walls,
there will come a time after X number of insects trapped when this
buildup of cells reduces the efficiency of the trap. Whether there
is an acceleration of the ageing process (whatever that exactly
means...) as some books state seems not to have been fully resolved
yet (or has it?), but this build-up might reduce the ease of
excretion of waste from the cells encouraging self-poisoning.
Perhaps some of the chemical products of digestion accumulate to
concentrations capable of poisoning the leaf (lactic acid?)
From a practical point of view a trap which is inefficient is
certainly less desirable to the plant than a brand new one which
stands a better chance of retaining the prey it attempts to catch.
Providing, of course, each trap on average provides sufficient
nutrients to at least replace itself.
So I guess the options for leaf expiration would be :
- internal plant chemistry, ie: ageing or poisoning by cell waste
- external digestion-related chemistry, ie: poisoning by unexcretable
digestion residues
- physical complications caused by the cell build-up on the outside
of the trap
- other (just to hedge my bets:)
- or a combination of the above.
Comments anyone ?
Peter
Peter Cole | carnivor@bunyip.demon.co.uk | wondering if I'm reinventing
Swansea, WALES | old mailboxes still active | the wheel a bit here :)