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Dating origin orchidaceae

This was a deliberate attack on the argument from design, and indeed on the notion of purpose in the world in general.

Even the title was ironic, for Paley had said that there can be no contrivance without a contriver. He showed how complex and remarkably effective adaptations could in fact be built up by small steps through natural selection.

The Harvard botanist Asa Gray was one of Darwin's ablest supporters, but the book on orchids was a bit much for Gray's religious sensibilities.

He devised a theory that John Dewey later called design on the installment plan: God works by natural selection but includes a dose of providence by guiding variation along definite lines.

The bizarre Catasetum orchids produce either male or female flowers, depending on the individual.

Male flowers have special triggers that literally flick away the pollinators they lure in the process of applying their pollinia.

The first book Darwin published after the On the Origin of Species (1859) was On the various contrivances by which British and foreign orchids are fertilised by insects (1862), also called Fertilization of Orchids. (2007) hypothesized orchids must have evolved at least 15-20 million years ago, during the Miocene, based on the finding of amber containing an extinct species of stingless bee, Proplebeia dominicana, that was carrying pollen of a previously unknown orchid taxon.

He wrote: While a candidate moth, the Madagascan sphinx moth Xanthopan morganii, had been catalogued from the Congo region of Africa in the 1830s, the Congo is a bit far from Madagascar and Darwin had no knowledge of it.

though said subspecies was ultimately determined to be identical to the mainland species.

often called Darwin's orchid, has an 18-inch long nectar-spur emanating from its labellum.

Knowing that sphinx moths (Sphingidae family) pollinate all of its relatives, Darwin predicted that there was a sphinx moth with an 18-inch long tongue that pollinates it.


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