Sixty-six million years ago, a massive asteroid struck the Earth and altered the course of life on the planet, a reminder that the story of living things has been written as much by catastrophe as by slow, patient change. A new study in the journal Science, drawing on tens of thousands of leaf and pollen fossils from what is now Colombia, turns attention away from the dinosaurs and toward the plants that inherited the wounded world. Its suggestion is quiet but significant: the forests we now associate with lush flowering canopies may owe their character to the impact and the long recovery that
Asteroid That Doomed the Dinosaurs May Also Have Shaped Today's Tropical Rainforests
In the rainforest, the dinosaurs' loss was the flowers' gain.
Sixty-six million years ago, a massive asteroid struck the Earth and altered the course of life on the planet, a reminder that the story of living things has been written as much by catastrophe as by slow, patient change. A new study in the journal Science, drawing on tens of thousands of leaf and pollen fossils from what is now Colombia, turns attention away from the dinosaurs and toward the plants that inherited the wounded world. Its suggestion is quiet but significant: the forests we now associate with lush flowering canopies may owe their character to the impact and the long recovery that followed.
Sixty-six million years ago, an enormous asteroid struck the Earth. Intense heat, giant tidal waves and a sky smothered in cloud followed, and in the years after, as much as three-quarters of land-based life disappeared. The dinosaurs are the losses most people remember, but a new study in the journal Science asks what the catastrophe did for plants.
An international team built its case on tens of thousands of fossils from what is now Colombia. By examining leaf and pollen remains, the researchers were able to reconstruct two very different forests. The older one was already warm and wet, yet it was crowded with conifers and ferns rather than the flowering plants that define rainforests today. Its trees stood far apart, allowing broad patches of light to reach the ground.
The team's central conclusion is that the impact and its aftermath, rather than the extinction alone, prepared the ground for the flowering, densely layered forests that came later. The excerpt available here describes the earlier landscape in detail but does not trace how the new forest emerged. For that account of the recovery, the full paper in Science is the place to turn.
Sixty-six million years ago, an enormous asteroid struck the Earth, and the planet's course changed. The impact is thought to have produced intense heat, set off tidal waves and shrouded the sky in cloud. In the aftermath, as much as 75 per cent of land-based life went extinct.
The dinosaurs are the casualties everyone remembers. A new study in the journal Science looks instead at what the catastrophe did for plants, and in the tropical rainforest the answer appears to be that the dinosaurs' loss was the flowers' gain.
An international team of researchers built the study on tens of thousands of fossils. They focused on plant life in what is now Colombia, tracing what happened there after the impact. Their conclusion is that the crash was probably responsible for the modern makeup of tropical rainforests, the flowering, densely layered forests we know today.
To understand what the region looked like before the extinction event, the team studied leaf and pollen fossils from the area. Those fossils, the researchers found, tell a story of two different forests.
The forest before the crash was already wet and warm. But it teemed with conifers and ferns rather than the plants that dominate rainforests now. The trees stood widely spaced, which let large patches of light reach the forest below. It was a tropical place, but not one that would look familiar to a visitor walking into a rainforest today.
The study's central claim is that the impact and its aftermath, not simply the extinction of the dinosaurs, laid the foundation for the flowering tropical forests that followed. The excerpt of the research available here describes the earlier forest in detail but stops short of laying out how the post-impact forest took shape. The full paper in Science is where that account of the recovery lives, and it is the place to look for how the change unfolded.
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