The oldest fossil flower
The textbooks tell us that flowers first appeared about 125 million years ago. But now a dig in northeastern China has turned up literally hundreds of fossil flower specimens. The structures of the flowers show that they’re from a group of plants called angiosperms - these are the common vascular, seed-bearing plants we see around today. But what’s extraordinary about these newly-found flowers is that they date from nearly 200 million years ago - proving flowers have been around for much longer than we first thought. Speaking with Chris Smith, Xin Wang made the discovery…
Xin - About two years ago we discovered many many specimens of a flower from the early Jurassic. Just in the suburb of Nanjing City. Early Jurassic means 174 million years before today.
Chris - So these are very ancient specimens! How do they fit into the timeline of what we understand about the evolution of flowering plants?
Xin - The mainstream idea about the evolution of flowers is that flowers only existed since 125 million years before. But our discovery is far far beyond the scope. And we have so many specimens we are very confident with our conclusion. They are angiosperms, and the flowers in the early Jurassic.
Chris - Could you describe what these particular flowers would have looked like for us?
Xin - Each flower is about a 13 millimetres in diameter. It's a very small flower.
Chris - And you say that these are angiosperm flowers? Why is that important?
Xin - Because in the textbooks people were taught there was no angiosperms, no flowers in the Jurassic; which means we have been misunderstanding the history of a flower and angiosperms.
Chris - And how did you make the discovery of these flowers - where did you find them, and in what sort of context?
Xin - Well the situation is there are many discoveries of early angiosperms in China; formally it's in the northeast China. My previous work also focused on the northeast. And we somehow just ignored something nearby! About two years before, one of my colleagues, Dr Fu, found the first sign of flower in the suburb of Nanjing. And then we went there together. We were so lucky that in the first half day we'd got more than 200 flowers, and sometimes a single piece of rock there are almost 80 flowers!
Chris - Why do you think these flowers are so well preserved and why are there so many of them where you discovered them?
Xin - The flowers are preserved in a different states and orientations. Because the huge number of specimens, it gave us a chance to observe the flower from different angle and perspectives, and the presentation is not always the same. Some of them we can see the internal structure. Some we don't. So, if we combine all that information from more than 200 flowers, we can reconstruct a single flower, which is what we did in the paper. And why the flowers are concentrated in this area is because the flower probably flourished in this small area, probably very close to water, and they didn't grow too much in a forest, or somewhere else. So, when they're preserved in some kind of lake or pond they are just buried there.
Chris - What do you think these flowers turned into? Can you see, or can you trace any further lineage or timeline from these flowers onwards in history?
Xin - Honestly, we have no information about this yet. We're know nothing earlier oe nothing later than this.
Chris - So, at the moment, we know that these flowers come from 175 million years ago or so, pushing back the date of the first flower by more than 50 million years. But, obviously, that doesn't mean that that's the precise moment when the flowers did first appear. So that means that the first flowers are even older than this doesn't it?
Xin - Yes definitely! And flower's history must be much older than this.
Chris - And in terms of what must have been going on in parallel, does this give us some insights into what animals were doing at the same time as the plants were evolving these flowers?
Xin - Current information about this flower doesn't suggest there were insects or animals involved in the pollination of the flowers. They have a dendroid form, which means it has an increased receptive area of the stigma, which is frequently seen in flowering plants which are pollinated by a wind rather than by insects...