Natures wonders: water wheel insect trap mechanism (Introduction)

by David Turell , Wednesday, May 16, 2018, 02:02 (2382 days ago) @ David Turell

Another plant beside the Venus fly trap catches insects, and by a different mechansim:

https://www.sciencedaily.com/releases/2018/05/180515105654.htm

"The midrib of the leaf (which has been transformed into a snap trap) bends slightly downwards in a flash, the trap halves fold in, and the water flea can no longer escape -- as part of an interdisciplinary team Anna Westermeier, Dr. Simon Poppinga and Prof. Dr. Thomas Speck from the Plant Biomechanics Group at the Botanic Garden of the University of Freiburg have discovered how this snapping mechanism, with which the carnivorous waterwheel (Aldrovanda vesiculosa) catches its prey, works in detail.

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"The Venus flytrap (Dionaea muscipula) and the far less known aquatic waterwheel are the only carnivorous plants with snap traps. While intensive research on the Venus flytrap has been going on for a long time, the ten times faster underwater snap traps of the waterwheel have so far been little studied. The team led by the Freiburg biologists has now deciphered the underlying movement principle using experiments and computer simulations. The researchers found that the waterwheel snaps shut its trap, which is only three millimetres in size, by actively changing the internal pressure in the cells of the leaf, which leads to the midrib bending, and also by releasing internal prestress, which apparently results in an acceleration effect. The Venus flytrap, on the other hand, employs a hydraulic mechanism to change the curvature of its leaf halves which results in rapid trap closure. Although both plants share many similarities, the mechanics of the traps differ considerably. This finding may not only help understanding the development of snap traps from an evolutionary perspective, but also the adaptation to different habitats -- in a terrestrial habitat with the Venus flytrap, under water with the waterwheel."

Comment: These plants demonstrate a very complex evolution. Not only must they work out the mechanics of a trap, they must develop a digesting enzyme to dissolve the insect, and at the same time develop a protection for itself from the enzyme. This is irreducible complexity, for which evolutionary theory has no explanation, since it all must be developed in one step to solve call the problems presented by the process or trapping and eating. Not by chance.