Biodiversity’s winners and losers

Publication:   Date: August 17, 2009   View Article

There are winners and losers on the racetrack of speciation – the process of species splitting into new species, according to Michael Alfaro, an evolutionary biologist at the University of California Los Angeles. He and his colleagues analyzed DNA and fossils from 44 major lineages of jawed vertebrates to calculate which ones have exceptionally fast and slow rates of speciation.

Eight great extinct species

Publication:   Date: July 19, 2008   View Article

The Caribbean monk seal has joined a long and growing list of species that carry the “extinct” label. Learn about this and seven other extinct species that have made headlines in recent years.

Mass Extinctions Due to Sea Level Changes, Study Says

Publication: National Geographic News   Date: June 17, 2008   View Article

The rise and fall of the seas may have a more lethal toll on Earth’s life than asteroids and supervolcanoes, according to a new study.

Over the past 540 million years, every increase in the rate of extinctions—including the five so-called mass extinctions—has been linked to environmental changes wrought by changing sea levels, the study says.

Growing Ocean Acidity May Erode Coastal Ecosystems

Publication: National Geographic News   Date: May 22, 2008   View Article

Ocean waters along North America’s west coast are becoming more acidic than expected in response to atmospheric carbon emissions, which will likely cause significant changes to economically vital marine ecosystems, a new study says.

One Degree of Warming Having Major Impact, Study Finds

Publication: National Geographic News   Date: May 14, 2008   View Article

Human-induced climate warming is already having a dramatic effect on Earth’s plumbing, plants, and animals, according to an exhaustive analysis of data from around the world.

The report’s individual findings are familiar and widely cited, such as cannibalistic polar bears, melting glaciers, and earlier-blooming plants.

But this is the first time the data have been compiled in a single study and directly linked to human activity, the report authors say.

Legless Lizard, Other New Species Discovered

Publication: National Geographic News   Date: May 2, 2008   View Article

Captions for photos of new species discovered in Brazil. Shots include a legless lizard, horned toad, a dragon-looking lizard, and a fat-tailed mouse.

Narwhal More at Risk from Warming than Polar Bear?

Publication: National Geographic News   Date: April 29, 2008   View Article

A porpoise with a long, spiraled tusk that inspired the myth of the unicorn ranks higher than the polar bear on a new list of marine mammals most at risk due to Arctic warming.

That’s because the narwhal, also known as the corpse whale, may be slightly more sensitive to habitat changes.

© 2008-2010 Collected Writings By John Roach