via Smithsonian

Charles Darwin – the father of the Theory of Evolution – looked at the innocent flowers around him and probably frowned.

The famous naturalist was obsessed with how the first flowering plants evolved and used the expression to refer to the question a few years before his death. His ideas explained that through natural selection living things were slowly and continuously adapting to changes in the environment. But something did not fit with the flowers.

He was so disturbed by this matter that Darwin referred to it as the “abominable mystery” of the flowers.


The Abominable Mystery

via Digital Sevilla

Darwin coined the expression “abominable mystery” in 1879 in a letter to his best friend, botanist, and explorer Dr. Joseph Hooker.

“The apparent rapid development of all higher plants in recent geological times is an abominable mystery,” he wrote at the time.

The mystery centers on the rise of flowering plants – or angiosperms – the family of plants that produce flowers and bear their seeds in the fruit. This makes up most of all known living plants, from oak trees to wildflowers to water lilies. Flowering plants appeared on Earth relatively recently on a geologic time scale, then rapidly diversified in an explosion of colors and forms.

“In the fossil record, they appear very suddenly in the Cretaceous, dated to about 100 million years ago. There is nothing that looks like an angiosperm before them, and then they appear suddenly and in considerable diversity,” Buggs stresses.

The advent of flowering plants suggested that evolution might be rapid and abrupt, in direct contradiction to an essential element of natural selection: nature does not make leaps.


The Mystery Today

via The Conversation

Particularly important fossils have been discovered that have helped to understand the early stages of the diversification of flowering plants and great progress has been made especially in the last 30 years.

Specifically, a team of researchers at UC Santa Cruz, in Santa Cruz (California, USA), has unraveled the mystery of why some plants have two different sets of anthers – part of the reproductive organ of a flower – and why they have two different sets of anthers.

Flowering plants often rely on bees and other pollinators to help them reproduce. However, pollen is the bees’ food, and if they have enough of it, they are more likely to forget to go to another flower. Kathleen Kay – associate professor of ecology and evolutionary biology at UC Santa Cruz – states:

“Plants have evolved ways to optimize the behavior of bees to maximize the transfer of pollen between flowers.”

The team found an explanation for heteronormality in wildflowers of the genus Clarkia.

“If a flower doses a bee with a ton of pollen, the bee is in pollen heaven, and it will start grooming and then go off to feed its offspring without visiting another flower. So, plants have different mechanisms for doling out pollen gradually. In this case, the flower is hiding some anthers and gradually revealing them to pollinators, and that limits how much pollen a bee can remove in each visit.”

Well, I guess you can now – finally – rest in peace, Charles.