According to new research, flowers found entirely preserved in globs of amber grew at the feet of dinosaurs, implying that certain blooming plants in South Africa today have remained unchanged for 99 million years.
The two blooms first appeared in what is now Myanmar, and they may provide insight into how blooming plants evolved – a significant event in the history of life that Charles Darwin famously described as an "abominable enigma."
Flowers are transient: they bloom, turn into a fruit, and then fade away. As a result, old flowers aren't commonly found in the fossil record, making these ancient blossoms and the history they contain even more valuable.
Unique Amber Flowers
According to Robert Spicer, emeritus professor in the School of Environment, Earth, and Ecosystem Sciences at the Open University in the United Kingdom and the study's lead author, leaves are frequently produced in greater quantities than flowers and are significantly more resilient – they have a better potential for preservation.
A leaf is discarded when it has served its purpose. In contrast, he explained that a flower turns into a fruit, which is then eaten or disintegrates as part of the seed dispersal process.
According to Spicer, a visiting lecturer at China's Xishuangbanna Tropical Botanical Garden, these flowers are nearly identical to their modern descendants. There are no significant differences.
Much of life as we know it today is thought to have been shaped by the growth and spread of flowering plants (angiosperms).
It resulted in the diversification of insects, amphibians, mammals, and birds, according to a study published on Monday in the journal Nature Plants.
Flowering plants reproduce more quickly than other plants and have more complicated breeding methods, such as a wide variety of flower shapes, which are frequently in close 'partnership' with pollinators.
As Spicer pointed out, this results in the mutual co-evolution of numerous plant and animal lineages, causing ecosystems to change.
One of the amber-preserved flowers was identified as Eophylica priscatellata, and the other as Phylica piloburmensis, both of which belong to the same genus as the common Phylica flowers found in South Africa today.
Is Darwin’s Mystery Solved?
Darwin was puzzled by the sudden appearance of flowering plants in the fossil record during the Cretaceous era (145 million to 66 million years ago), with no obvious parental lineage from previous geologic periods.
It appeared to contradict a fundamental component of his natural selection hypothesis – that evolutionary changes occur slowly and over a long period of time.
In a private letter to botanist Joseph Hooker in 1879, Darwin described it as a "abominable riddle," which was published in a 1903 book of Darwin's correspondence.
The precise date when blooming plants first appeared, according to Spicer, is unknown, but the early blossoms preserved in amber provide some insight into the mystery.
The characteristics of the specimens are similar to those observed in fire-prone blooms, such as those found in South Africa's unique fynbos regions.
This ecologically diverse and rich environment is home to all 150 Phylica species. They were also discovered near amber that had been partially burned.
'Fire Must Have Been Common Occurrence'
Assume that many early flowers were exposed to fires in semi-arid environments. That explains why the early stages of angiosperm development are so poorly represented in the fossil record – as he stated, fossil(s) do not generally form in such semi-dry habitats.
According to Spicer, the fire must have been a common occurrence for a long time for evolution to shape the flowers into a form that could withstand fire and produce seeds that could pass through the charred ground surface.
The blooms of Phylica are protected by leaves that cluster at the twig tip.
While many ferns, conifers, and flowering plants that we see today, such as plane trees and magnolias, thrived during the dinosaur era, Spicer claims that Phylica piloburmensis was the first flowering plant known to have an almost identical cousin that is still alive today.
Only amber fossils from the dinosaur era have been discovered in deposits from Kachin State in northern Myanmar.
Human rights violations have raised ethical concerns about the origins of amber from the area in recent years.
After the country's military took control of some amber mining sites in 2017, the Society of Vertebrate Paleontology recommended a moratorium on research on amber derived from Myanmar. Spicer stated that the amber was obtained legally from local dealers prior to 2016 using the procedures in place at the time.
(Source: Optic Flux)
