100-million-year old amber fossil reveals ancient reproduction in flowering plants

Researchers have discovered a 100-million-year old piece of amber which reveals the oldest evidence of sexual reproduction in a flowering plant- a cluster of 18 tiny flowers from the Cretaceous Period.

It was found that one of them in the process of making some new seeds for the next generation.

The perfectly-preserved scene, in a plant now extinct, is part of a portrait created in the mid-Cretaceous when flowering plants were changing the face of the Earth forever, adding beauty, biodiversity and food. It appears identical to the reproduction process that “angiosperms,” or flowering plants still use today.

Researchers from Oregon State University and Germany found that the flowers themselves are in remarkable condition, as are many such plants and insects preserved for all time in amber.

The flowing tree sap covered the specimens and then began the long process of turning into a fossilized, semi-precious gem. The flower cluster is one of the most complete ever found in amber and appeared at a time when many of the flowering plants were still quite small.

Even more remarkable is the microscopic image of pollen tubes growing out of two grains of pollen and penetrating the flower’s stigma, the receptive part of the female reproductive system.

This sets the stage for fertilization of the egg and would begin the process of seed formation- had the reproductive act been completed.

George Poinar, Jr., a professor emeritus in the Department of Integrative Biology at the OSU College of Science, said the pollen of these flowers appeared to be sticky, suggesting it was carried by a pollinating insect, and adding further insights into the biodiversity and biology of life in this distant era.

The study was published in the Journal of the Botanical Institute of Texas. (ANI)