Colombia’s rain forest looked on very different 66 million years ago. In the meantime, the humid habitat and natural vegetation is covered with a sturdy roof, with a slight shield of leaves and twigs. Basically, nothing and dinosaurs. But before the dinosaurs arrived with the effects of the Chicxulub, marking the end of the Cretaceous period, things looked very different. Natural feeding in the area was limited, and a bevy of conifers called it a home.
Application the past plant residues, a team of researchers studied the history of the rain forest and how the asteroid formed modern rain forests. The program of learning, published in Science on April 1, he was led by scientists at the Smithsonian Tropical Research Institute (STRI) in Panama and assisted by scientists at the Negaunee Institute for Plant Conservation Science and Action at the Chicago Botanic Garden.
“Forests are disappearing because of nature … then, the plants are controlled by flowers,” said Mónica Carvalho, author and co-author of STRI and Universidad del Rosario in Colombia, in an interview with Ars.
The study began 20 years ago, with parts of the team collecting and analyzing 6,000 leaves and 50,000 pollen grains from Colombia. These archeology allowed the team to identify the type of plants that existed before and after the asteroid. This system represents a regional variation between 72 million and 58 million years ago, which affected both before and after the event. “It took us a long time to gather enough to be able to better understand what happens at the end,” Carvalho told Ars.
Concerning the Colombian archeology, Carvalho said the researchers were well aware of what was happening in the jungles of some parts of Central and South America, although the severity of asteroids varies from region to region. “It’s a bit of a change. So far we don’t know why some areas were affected more than others,” he said.
Prior to asteroid hit the Earth, nearly half of all plant species in Colombia were destroyed – the pollen grains of those species have disappeared after that. The rain forest began to be stripped of ferns and flowers that, although previously affected, were much smaller than they are today. Coniferous trees, by comparison, are extinct.
Aside from the presence of conifers, the rain forests of the past were probably smaller than their present counterparts. Today’s rain forests have larger strands, and the vegetation is grouped together, meaning that most plants release water into the atmosphere. This results in more moisture and cloud coverage According to Carvalho, low humidity in the early forests means that the areas were probably less productive than they are today.
But the lowest forest remained until the asteroid hit. “Only after we saw the forests change its design,” he said.
The researchers have some ideas for how it changes. The first is the end of and dinosaurs caused the forest to grow – there would be fewer animals eating vegetation or treading on the grass, allowing its leaves to grow unchecked. The second theory is that, as soon as the asteroid collided with the earth, there was a selective extinction of conifers in tropical areas — they could have been a little better than their flowering counterparts after exposure.
Third is that the effects of the catastrophe can produce soil. The aftermath of the tsunami would have carried away debris and mud from the carbon-rich, shallow areas of the surrounding water. A blazing fire could have released ash from the atmosphere, and if it had settled on the ground, it would have been like fertilizer. Flowering plants grow better than conifers in fertile soil, says Carvalho. He also said that both, or both, can be true at the same time.