Mother Nature is a great photographer and she knows how to preserve precious moments, just as how an amber from 100 million years back preserved tiny flowers in the middle of producing seeds to ensure its continuity. From the Cretaceous era, nature kept 18 small flowers safe to be appreciated at a time when people can print out rocket parts on their desktop.
Experts from the Oregon State University acquired the fossilized flowers that are now extinct from diggers in the Hukawng Valley in Myanmar. The specimen is the oldest evidence of how flowering plants sexually reproduce.
"In Cretaceous flowers we've never before seen a fossil that shows the pollen tube actually entering the stigma. This is the beauty of amber fossils. They are preserved so rapidly after entering the resin that structures such as pollen grains and tubes can be detected with a microscope," explained OSU Department of Integrative Biology professor George Poinar, Jr.
"The evolution of flowering plants caused an enormous change in the biodiversity of life on Earth, especially in the tropics and subtropics. New associations between these small flowering plants and various types of insects and other animal life resulted in the successful distribution and evolution of these plants through most of the world today. It's interesting that the mechanisms for reproduction that are still with us today had already been established some 100 million years ago."
According to the experts, the preserved scene shows pollen tubes from ancient seeds penetrating the stigma or the female reproductive system of the flower. If the process was not interrupted by the sap that turned into amber, fertilization would have taken place and new seeds would have been produced.
Under scrutiny, Poinar noted that the seeds were brought by insects during mid-Cretaceous when the environment was covered by mosses, ferns, cycads and conifers. Most likely, the seeds were brought by 3-millimeter bees that existed before in Myanmar. During that time, flowering plants just started to appear concurrently with the appearance of new birds and mammals.
Poinar and his colleagues have published the results of their study in the current issue of Journal of the Botanical Institute of Texas.
