LIFE × EVOLUTION
The First Flowers
~140 million years ago (origin debated)
Phanerozoic · Mesozoic · Cretaceous
A flower does two things at once: it locks the seed inside a container, and it advertises to an animal. The container is what makes a plant an angiosperm, and when the group began is the longest-running argument in botany. Unmistakable fossils start about 135 million years ago; a count of fifteen thousand fossil occurrences across two hundred families puts several of those families in the Jurassic, and one molecular clock goes back further still, to the end of the Triassic. Whatever the origin, the spread is Cretaceous: lineages pile up between 125 and 72 million years ago.
Why it matters
Three quarters of living plant species are flowering plants, and so is nearly everything on a dinner plate. They also rebuilt food webs on land from the bottom up: more insects, then more of the birds and mammals that eat them.
Dating & uncertaintyDisputed
Unequivocal angiosperm fossils begin in the Early Cretaceous, near 135 to 125 Ma, while analyses that correct for incomplete sampling, and most molecular clocks, place the origin in the Jurassic or earlier. The gap between the two has a name, the Jurassic angiosperm gap, and what it turns on is whether the first flowering plants existed without leaving fossils, or did not yet exist.
Sources
- Sun et al. (2002), Science · Archaefructaceae, a new basal angiosperm family
- Silvestro et al. (2021), Nature Ecology & Evolution · Fossil data support a pre-Cretaceous origin of flowering plants
- Li et al. (2019), Nature Plants · Origin of angiosperms and the puzzle of the Jurassic gap
- Magallón et al. (2015), New Phytologist · A metacalibrated time-tree documents the early rise of flowering plant phylogenetic diversity
Earth history as one day
23:15:3544 min 24 s before midnight
if Earth’s 4.54 billion years were compressed into a single day
See it on the timeline