04-24-2003 - Biodiversity

sagar: Author=’Jorge Salazar’ program=’3762′ video=”Milford Sound, New Zealand. Photo by Dov Sax._JB:_ This is Earth and Sky. Across the planet, the variety of plants and animals is waning at an alarming rate. But on some islands, biodiversity is actually increasing.

_DB:_ Dov Sax – an ecologist at UC Santa Barbara – has studied changes in the diversity of plants and birds on over a dozen islands. His group has found that – as bird species become extinct – others replace them – so that the total number of bird species has remained more or less constant.

_JB:_ Plants have been found to undergo few extinctions and many naturalizations – causing plant species to double on the islands. Is this a good thing? No one knows. Here’s Dr. Sax.

_Dov Sax:_ Just because diversity is going up on these islands, doesn’t mean that these islands are in any way healthy or from a conservation perspective, that this is in any way desirable.

_DB:_ Sax says it remains to been seen what effect this increased diversity will have on what he calls “ecosystem functioning.” That term describes the secret life of plants, animals and microbes – activities like feeding and growing that physically and chemically change the environment. By the way, most scientists agree – many of these shifts in bio diversity are the result of human activity.

_JB:_ We have a transcript of our interview with Dr. Sax – come to today’s show at earthsky.org. Thanks today to the “U.S. Forest Service”:http://www.fs.fed.us/ and to the “National Fish and Wildlife Foundation”:http://www.nfwf.org/. We’re Block and Byrd for Earth and Sky.

Written by EarthSky