DARWIN Charles Insectivorous Plants. Second thousand.

Freeman, F-1218 ; voire Norman, 601 (premier tirage).

Édition originale, deuxième tirage, de cette importante étude sur les plantes carnivores.

“Darwin’s work on insectivorous plants began by accident. While on holiday in the summer of 1860, staying with his wife’s relatives in Hartfield, Sussex, he went for long walks on the heathland and became curious about the large number of insects caught by the common sundew (Drosera rotundifolia)…. Most of Darwin’s experimental work was on Drosera and this was subject of the first twelve chapters of his resulting book. After Dionaea, of all the other insectivorous plants he worked on, Darwin spent the most time studying Utricularia (bladderworts). At first he could not work out how they caught their prey, finding it difficult to manipulate the tiny bladders under the microscope, and complaining ‘The negative work takes five times more time than the positive.’ The breakthrough came when aristocratic horticulturist Dorothy Nevill leant him a plant of Utricularia montana… Insectivorous plants was published on 2 July 1875 and it was immediately clear that Darwin had been too desponding about the potential sales of the work, as 1700 copies sold straight away. A second and third thousand copies were printed off quickly with a fourth thousand following in 1876″ (University of Cambridge, Darwin Correspondence Project).

“Among carnivorous plants, Darwin was particularly fascinated by the speed and sensitivity of snap-traps in Dionaea and Aldrovanda. Recent molecular work confirms Darwin’s conjecture that these monotypic taxa are sister to Drosera, meaning that snap-traps evolved from a ‘flypaper’ trap. Transitions include tentacles being modified into trigger hairs and marginal ‘teeth’, the loss of sticky tentacles, depressed digestive glands, and rapid leaf movement. Pre-adaptations are known for all these traits in Drosera yet snap-traps only evolved once. We hypothesize that selection to catch and retain large insects favored the evolution of elongate leaves and snap-tentacles in Drosera and snap-traps. Although sticky traps efficiently capture small prey, they allow larger prey to escape and may lose nutrients. Dionaea’s snap-trap efficiently captures and processes larger prey providing higher, but variable, rewards. We develop a size-selective model and parametrize it with field data to demonstrate how selection to capture larger prey strongly favors snap-traps. As prey become larger, they also become rarer and gain the power to rip leaves, causing returns to larger snap-traps to plateau. We propose testing these hypotheses with specific field data and Darwin-like experiments. The complexity of snap-traps, competition with pitfall traps, and their association with ephemeral habitats all help to explain why this curious adaptation only evolved once” (Donald M. Waller, in : New Phytologist, 17 July 2019).

Quelques usures à la reliure, sinon très bon exemplaire de travail.

Provenance : Joseph Gibert (cachet humide sur le titre).