When the first flowers opened on Earth, this is what they looked like

Flowers evolved during the era of the dinosaurs.

Scientists have reconstructed the appearance of the first flower, which has at least 10 gently curving and well-spaced petals.

Flowering plants make up about 90% of the plants on earth. Their common ancestor lived about 140 million years ago, during the time of the dinosaurs. Despite this amazing evolutionary success, the origin of flowers has remained something of a mystery. Due to their fragility, flowers have not been widely preserved in the fossil record.

Now a study published in Nature Communications has revealed a 3D model of scientists' impression of what the ancestor of all flowers looked like.

"A key question in evolutionary biology concerns the origin of the angiosperms and of their most important defining structure, the flower," the authors, led by Hervé Sauquet of the University of South Paris, write in the study.

The study uses the largest dataset of floral traits ever assembled – using 13,444 data points, representing 792 different species. From the floral traits of the many flowering plants alive today, the researchers traced back their common features to shed light on their evolution.

"This approach allows us to uncover important clues on the origin and subsequent diversification of the flower by providing estimates of what flowers were like at key points in time," the authors write.

The study has revealed that the earliest flowers were most likely to have been both male and female, rather than having just one sex. As well as having about 10 petals, the flower also probably had more than 10 stamens (the male part of the flower) and five carpels (the female part of the flower). No other living flower has this flower's exact combination of characteristics.

Even so, the study doesn't conclusively describe the first flowers. Lucky discoveries in the fossil record could give scientists a much clearer view of the first flowers. And despite this discovery, much remains to be found out about the early emergence of flowers.

"The origin of the angiosperm flower remains among the most difficult and most important unresolved topics in evolutionary biology," the authors conclude.