Amazonian biodiversity much older than originally thought

Nov 29, 2010
This is Pauji-yuyo in Bolivia. Credit: University of Gothenburg

Amazonia's huge biodiversity originated with the formation of the Andes and, as such, dates back further than previously realised, claims an article written by an international research group, headed by a researcher from the University of Gothenburg, published in the journal Science.

"With the results we present in this article, we've rewritten the entire history of Amazonia in terms of the development of its biodiversity," says Alexandre Antonelli from the University of Gothenburg's Department of Plant and Environmental Sciences, and scientific curator at the Gothenburg Botanical Garden (Sweden).

Amazonia's wealth of species is by far the greatest in the world. Although researchers have long suspected that the diversity of the Amazonian rainforest was affected by the , the causal links have been unclear until now, and there have been a wide range of scientific theories on the origins of the species found there.

A team of researchers led by Antonelli and the University of Amsterdam's Carina Hoorn has now compared the pattern of today's biodiversity in Amazonia with geological and molecular data for the last 65 million years – ever since the South American continent separated from Africa and the dinosaurs became extinct.

"We suspected from some scattered fossils and dated species trees that the Amazonian diversity arose after the separation from Africa. So we looked at the whole period. I worked mainly on coordinating a survey of DNA-based studies of the relationships between different species of plants and animals. We've examined hundreds of scientific publications and have found that very few of the genera are as young as people thought."

The collated results show that the greatest is to be found in connection with the Andes, an area that formed when the tectonic plates along the Pacific coast were pressed together to create this mighty range of mountains. The new mountains had a major impact on the environment, with living conditions changing fundamentally for plants and animals in Amazonia. The restructuring of the Earth's crust changed the large wetland areas found in northern South America, which dried up as the Amazon River formed. This, in turn, opened up new land for colonisation by plants and animals.

"We were surprised that there was such a strong link between the formation of the Andes and the diversity in Amazonia," says Antonelli, who was born in Brazil. "The area was considered a kind of paradise where evolution could take place undisturbed, but this hasn't been the case at all – a lot has happened in the region."

Explore further: Scientists discover tropical tree microbiome in Panama

More information: www.sciencemag.org/cgi/content/short/330/6006/927

add to favorites email to friend print save as pdf

Related Stories

Amazonian amphibian diversity traced to Andes

Mar 10, 2009

Colorful poison frogs in the Amazon owe their great diversity to ancestors that leapt into the region from the Andes Mountains several times during the last 10 million years, a new study from The University ...

Disappearing glaciers enhanced biodiversity

Oct 04, 2010

Biodiversity decreases towards the poles almost everywhere in the world, except along the South American Pacific coast. Investigating fossil clams and snails Steffen Kiel and Sven Nielsen at the Christian-Albrechts-Universitat ...

Thousands of plant species likely to go extinct in Amazon

Jul 09, 2009

As many as 4,550 of the more than 50,000 plant species in the Amazon will likely disappear because of land-use changes and habitat loss within the next 40 years, according to a new study by two Wake Forest University researchers.

Recommended for you

Global wild tiger population to be counted by 2016

1 hour ago

Thirteen countries with wild tiger populations agreed Tuesday to take part in a global count to establish how many of the critically endangered animals are left and improve policies to protect them.

Scientists discover tropical tree microbiome in Panama

16 hours ago

Human skin and gut microbes influence processes from digestion to disease resistance. Despite the fact that tropical forests are the most biodiverse terrestrial ecosystems on the planet, more is known about ...

How are hybridized species affecting wildlife?

21 hours ago

Researchers who transplanted combinations of wild, domesticated, and domesticated-wild hybridized populations of a fish species to new environments found that within 5 to 11 generations, selection could remove ...

User comments : 0