Today is the anniversary of the death of Charles Darwin (12 February 1809 – 19 April 1882). In tribute to the naturalist, we look at his ‘Abominable Mystery’.
Charles Darwin was concerned with the fossil record showing the sudden and rapid diversification of the flowering plants. These concerns were expressed in a letter he wrote on 22nd July 1879 to his close friend Joseph Hooker:
Origins of Flowering Plants
Darwin speculated that they arose in response to a rise in ‘flower frequenting insects’. In fact we now understand that the co-evolution of plants and insects was an important process in the flowering plants’ origins and divergence. Put quit simple: no insects, no flowering plants.
The relationship between the two has been one of love and hate.
Love – the plants exploiting the insect for sex (transfer of pollen) by offering food, shelter and other rewards.
Hate – the plants having to defend themselves against the attack of insects using them for food.
The processes continue today.
We now know that the flowering plants arose in the Early Cretaceous, around 130 million years ago. By the mid Cretaceous they had rapidly diversified and spread around the world with 50 families recognised.
This special fossil is called Bevhalstia plebja and was found in 1995 at Smokejacks Quarry, a Weald clay (Lower Barremian) brick-pit in Surrey. It was described by C.R. Hill in Cretaceous Research (1996) 17, 27-38. Further examples of this strange plant have subsequently been found.[slideshow]
Bevhalstia appears to be an unremarkable water weed growing on the margin of a pond or marsh. Far from being unremarkable it is a unique plant that does not match any living flowering plant. It has tiny flower buds at the ends of some of its branches that lack defined flower petals. It has leaves with veins like the leaves of modern flowing plants.
This is an amazing plant – a true ancestor, the earliest known, of all the amazing flowering plants and featured in a National Geographic article.
Gerald Legg, Keeper of Natural Sciences