Fewer species, less stability

<body leftmargin="0" bgcolor="#000060" text="#FFFFFF" link="#FFFF00" vlink="#FF9900"> <p class="MsoNormal"><b><font size="4" face="Arial">Fewer species, less stability</font></b></p> <p class="MsoNormal"><font face="Arial"><font size="1">Posted Jan. 25, 2005<br> Special to World Science</font> <b> <font size="2" face="Arial"><br> <br> </font> </b> </font> <b> <font face="Arial" size="2">A study of ancient coral reefs has shown that a greaer number of more diverse species can promote a stable environment over million-year timescales, experts say.</font> </b> </p> <p class="MsoNormal"> <b> <font face="Arial" size="2">Coral reefs are underwater ridges of hard material built up from the skeletons of reef-building coral, a small primitive marine animal, and other marine animals and algae over thousands of years. They occur in clear, shallow and sunlit seas. They are one of the world’s most productive and diverse ecosystems.<br> <br> Wolfgang Kiessling of Humboldt University in Berlin extracted data on the diversity of species living on ancient coral reefs from a database of fossil records called PaleoReefs. <br> <br> Over ten-million-year periods, he found that a higher average diversity of reef-building species produced smaller changes in the reef’s skeleton, architecture and species in subsequent time intervals. <br> <br> Because this rule held true over a wide spectrum of different reef types, it supports the hypothesis that species richness can promote ecological stability, he said.<br> <br> The findings are published in the Jan. 27 issue of the research journal Nature. Commentators writing in a separate article in the journal observed that the study is a much scaled-up version of smaller experiments that previously had reached similar conclusions.<br> <br> “It is remarkable that Kiessling’s findings agree with those derived from mathematical models, bottles, Petri dishes, aquaria, growth chambers and field plots, which often run for only a handful of generations,” wrote the commentators, Shahid Naeem and Andrew C. Baker of Columbia University in New York City.</font> </b> </p> <p class="MsoNormal"> <font size="2" face="Arial"><a href="http://groups.yahoo.com/group/world-science">http://groups.yahoo.com/group/world-science</a></font> </p> </body>