microrobert
08-11-2013, 06:58 PM
Ecosystems still feel the pain of ancient extinctions
It's not just humans that still feel the effects of a trauma many years later: ecosystems do too. Thousands of years after human hunters wiped out big land animals like giant ground sloths, the ecosystems they lived in are still feeling the effects.
Many ecosystems rely on big animals to supply them with nutrients, mostly from dung. "If you remove the big animals from an ecosystem, you pretty much stop nutrients moving," says Chris Doughty (http://www.eci.ox.ac.uk/people/doughtychris.php) of the University of Oxford.
Doughty and colleagues simulated the distribution of phosphorus, a nutrient that plants need to grow, in the Amazon basin in South America. This area was once home to spectacularly large animals, including the elephant-like gomphotheres and giant ground sloths.
Ecosystems still feel the pain of ancient extinctions - life - 11 August 2013 - New Scientist (http://www.newscientist.com/article/dn24026-ecosystems-still-feel-the-pain-of-ancient-extinctions.html#.UgfeNiRV3cc)
It's not just humans that still feel the effects of a trauma many years later: ecosystems do too. Thousands of years after human hunters wiped out big land animals like giant ground sloths, the ecosystems they lived in are still feeling the effects.
Many ecosystems rely on big animals to supply them with nutrients, mostly from dung. "If you remove the big animals from an ecosystem, you pretty much stop nutrients moving," says Chris Doughty (http://www.eci.ox.ac.uk/people/doughtychris.php) of the University of Oxford.
Doughty and colleagues simulated the distribution of phosphorus, a nutrient that plants need to grow, in the Amazon basin in South America. This area was once home to spectacularly large animals, including the elephant-like gomphotheres and giant ground sloths.
Ecosystems still feel the pain of ancient extinctions - life - 11 August 2013 - New Scientist (http://www.newscientist.com/article/dn24026-ecosystems-still-feel-the-pain-of-ancient-extinctions.html#.UgfeNiRV3cc)