New York, April 5 (IANS) The impact of asteroids that wiped out dinosaurs on Earth also gave birth to the Amazon rainforest, according to a new study.
In an analysis of thousands of pollen and fossil leaves, the researchers found that the impact of the cataclysmic asteroid that destroyed nearly 75% of all life on Earth drastically restructured rainforests.
It set the stage for the evolution of what has become one of the most diverse ecosystems on the planet – the Neotropical rainforest, according to the study published in the journal Science.
While the impact of the late Cretaceous almost 66 million years ago was catastrophic for terrestrial ecosystems around the world, its long-term effects on tropical forests have remained a mystery.
This is largely due to the lack of paleobotanical exploration in the region, which is only just beginning to provide the data needed to assess these questions.
For the study, Monica Carvalho of the Smithsonian Tropical Research Institution in Panama, and her colleagues used fossil pollen and leaves recovered from Colombia to characterize how the impact changed the rainforests of South America, finding changes large-scale in species composition and forest structure.
According to the results, the humid tropical forests of the Late Cretaceous were characterized by an open canopy environment.
However, plant diversity declined by about 45 percent at the Cretaceous-Paleogene border (K / Pg) and extinctions were widespread, especially among seed plants.
As forests recovered over the next six million years, angiosperms, or flowering plants, came to dominate forests, according to the study.
This transition has led to the closed canopy structure and vertical layered distribution of plant biodiversity that defines modern tropical rainforests, according to the study.
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