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#26: Are current projections of climate change-impacts on biodive Author: adediosLocation: Angel C. de Dios PostPosted: Wed Nov 21, 2007 3:08 pm
21 November 2007

Are current projections of climate change-impacts on biodiversity misleading?

This is the urgent question arising from the study “Quaternary climate changes explain diversity among reptiles and amphibians”, published in the journal Ecography.

Why is life on Earth not evenly distributed? Geographic patterns of species diversity and their underlying processes have intrigued scientists for centuries, and continue to spur scientific debate. Studies carried out over the past 20 years have led to the conclusion that species diversity is best predicted by contemporary patterns of energy and water, the so-called “contemporary climate” hypothesis. Because current climate gradients are correlated with past climate variability, it has also been suggested that current climate acts as a surrogate for evolutionary processes that have been triggered by past climate variability, giving rise to the “historic climate” hypothesis. Now, new high-resolution data on historic climate has allowed Dr Araújo in collaboration with Dr Rahbek and other colleagues to finally directly test the “historic climate” versus “contemporary climate” hypotheses of biological diversity. Their illuminating results are published in a recent paper in Ecography. Contrary to the expectations of many scientists they found that historic climate variability was a better predictor of reptilian and amphibian diversity in Europe than contemporary climate.

“The lack of quantitative spatial data on variation in climate over historical time has prevented more rigorous testing of these diverging hypotheses”, says Dr. Miguel B. Araújo from the National Museum of Natural Sciences (CSIC) in Madrid. As a consequence, “the debate on the causes of diversity gradients has turned to some degree into a discussion of semantics”.

Recent developments in general climate models have finally facilitated high resolution predictions of past climates. In collaboration with leading climatologists working on paleoclimate modeling in the United Kingdom, Drs. Araújo, Rahbek and colleagues provide the first comparative test capable of differentiating between the contribution of contemporary and historical climate drivers of diversity gradients across a complete lineage of species at a continental scale.

“In recent years, analytical attempts to shed light on the role of history in determining today’s patterns of species richness have focused on the strong residual variation of models using contemporary climate”, explains Dr. Carsten Rahbek from the Center of Macroecology at the University of Copenhagen. “It has been argued that these residuals provide information about the role of historical rather than contemporary constraints. However, such an analytical approach assumes that contemporary climate is the main explanatory force. In other words, the contemporary and historical hypotheses are not tested simultaneously in a directly comparable manner, and historical hypotheses are only invoked to explain what is left to elucidate after the implementation of contemporary environmental processes”, says Dr. Rahbek.

“Our results are striking in that they contradict previous studies of large-scale patterns of species richness” affirms Dr. Rahbek. “They provide the first evidence, using a quantitative analytical approach, that historic climate can contribute to current patterns of richness independently of, and at least as much as contemporary climate”. This study has profound implications for the study of diversity on Earth, and challenges the current view that patterns of contemporary climate are sufficient to explain and predict diversity.

Differentiating between contemporary and historical hypotheses is important, not only for theoretical reasons: “an understanding of the mechanisms that generate and maintain diversity provides valuable insights for predicting the impacts of contemporary climate changes on biodiversity”, says Dr. Araújo. “If contemporary climate does drive species richness, then current climate variables could be used to accurately predict the effects of climate change on biodiversity. If, as shown in our study, the mechanisms underlying contemporary patterns of species richness are in fact strongly influenced by the history of climate, then current-climate predictions may be seriously misleading and alternative approaches to predict the effects of climate change on biodiversity must be developed”.

#27: Catastrophic Impacts Made Life Flourish Author: adediosLocation: Angel C. de Dios PostPosted: Mon Dec 17, 2007 2:47 pm
Catastrophic Impacts Made Life Flourish
By Dave Mosher, LiveScience Staff Writer

posted: 17 December 2007 07:59 am ET

Space rocks are blamed for a lot of rough times on Earth, from the die-off of most marine animals some 250 million years ago to the disappearance of the dinosaurs 65 million years in the past.

A new theory, however, suggests that catastrophic meteorite impacts are linked to an explosion in biodiversity about 470 million years ago, during the Ordovician Period. Within a few million years, the number of trilobite species and scores of other creatures on Earth jumped at least three to four times.

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#28: Behind the Scenes:New Species Found in Mysteriously Diverse Author: adediosLocation: Angel C. de Dios PostPosted: Fri Dec 21, 2007 5:30 pm
Behind the Scenes:New Species Found in Mysteriously Diverse Jungle
By Chris Austin, Louisiana State University

posted: 21 December 2007 12:02 pm ET

This Behind the Scenes article was provided to LiveScience in partnership with the National Science Foundation. Chris Austin’s fieldwork takes him to some of the most inaccessible places on Earth in the pursuit of knowledge about the diversity of the world’s amphibians and reptiles. He serves as assistant curator of Herpetology and assistant professor of Biological Science at the Louisiana State University Museum of Natural Science and Department of Biological Science. This story relates some of the trials, tribulations, and triumphs of field work in remote New Guinea.

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#29: The centennial of the USS Albatross Philippine Expedition Author: adediosLocation: Angel C. de Dios PostPosted: Thu Dec 27, 2007 9:59 am
The centennial of the USS Albatross Philippine Expedition
STAR SCIENCE By Teodora Uy Bagarinao, PhD
Thursday, December 27, 2007
Pop quiz, hot shots! It is the centennial of the USS Albatross Philippine Expedition, there are no bombs on board, what do you do? You travel back in time and get on board!

Well, a Filipino is doing just that. Round-trip ticket and accommodations courtesy of the Fulbright Visiting Scholar Program of the US Department of State. To live at the nation’s capital no less! And work at the Smithsonian Institution, too, with some of the world’s finest biodiversity experts!

Now the time travel begins. Just over a hundred years ago, relations between the Philippines and the United States started with a bloody war, but in 1907-1910, the United States accomplished something the Philippines should forever be thankful for — the USS Albatross Philippine Expedition. The USS Albatross was the world’s first large deep-sea oceanographic and fisheries research vessel, and the Philippine Expedition became the first scientific exploration of the archipelago and the largest biodiversity collection from Philippine waters.

At the start of the American occupation, a surgeon working with the US Army sent samples of the tiny but abundant goby sinarapan from Lake Buhi, Camarines to Hugh McCormick Smith at the US Bureau of Fisheries, then based at the Smithsonian Institution in Washington DC. Smith described sinarapan as Mistichthys luzonensis in 1902. After the Philippine-American War, the US Bureau of Fisheries sent the steamer USS Albatross on an expedition under the direction of HM Smith to survey and assess the aquatic resources of the Philippines. The ship sailed from San Francisco on Oct. 16, 1907 and steamed into Manila Bay on Nov. 28, 1907. Over the next two years, the Albatross made nine cruises around the Philippines and a cruise around Indonesia, and finally left Manila in late January 1910.

The USS Albatross Philippine Expedition collected about 100,000 fish specimens, as well as countless invertebrates, reptiles, birds, and mammals, along with fisheries and oceanographic data. Most of the materials were deposited in the Smithsonian Institution’s National Museum of Natural History. The alcohol-preserved specimens are in excellent condition, 100 years on, and they are accessible to all people (with prior arrangement, of course) and for posterity.

The fishes and mollusks were promptly studied and many publications soon came out. Many of the collections were described in the United States National Museum Bulletin 100, issued in 14 volumes (38 separate titles) between 1917 and 1950, under the general title Contributions to the Biology of the Philippine Archipelago and Adjacent Region, including reports on diatoms, foraminiferans, sponges, coelenterates, bryozoans, mollusks, polychaetes, chaetognaths, copepods, echinoderms, tunicates, and fishes. Hundreds of beautiful color paintings of fishes and invertebrates from the Philippine expedition were produced by the Japanese artist Kumataro Ito. Publications on the USS Albatross collections have continued to come out over the years, including several on cephalopods, crustaceans, and ahermatypic corals.

The USS Albatross expedition is highly significant for the Philippines. The Philippines’ reputation as a megadiversity country may well be because marine biodiversity was so well documented by the USS Albatross expedition. The Albatross explored waters that had never been sampled before and, in many cases, have never been sampled again. Some of the fishes taken by the Albatross have never been collected since. Many of the Philippine species deposited at the Smithsonian are not even found in the Philippine National Museum. The USS Albatross Philippine Expedition was colonial science a hundred years ago, but already it was a demonstration of good research practice — a well-planned expedition; proper processing, documentation, and disposition of samples; and publication in permanent form. The Smithsonian scientists produced scientific papers that underpin much of taxonomy in the Philippines and the entire Indo-Pacific. The taxonomy and the scientific names may have changed with further research and the necessary revisions over the years, but the original specimens and descriptions still exist for verification.

The centennial of the USS Albatross Philippine Expedition provides an opportunity for me to collaborate with Smithsonian scientists on a research project of mutual interest and benefit. During the next five months, I will study the biological collections, the research publications, and the history of the USS Albatross Philippine Expedition, and write a book that informs both the American and Filipino general public about the enormous biodiversity in the Philippines and the great scientific achievements of that expedition. As part of the project, I will share my experiences and findings during the time travel, so you will hear from me every month. Please join me. All aboard!!! Visit the USS Albatross website ( www.nmnh.si.edu/vert/albatross ).

* * *

Doris Bagarinao, PhD, is the curator of SEAFDEC FishWorld, SEAFDEC Aquaculture Department (AQD) Museum in Tigbauan, Iloilo. At AQD, she has pursued research and conducts lectures on marine biodiversity in the Philippines, collection and identification of fishes, mollusks, crustaceans, corals, other aquatic animals, mangrove ecology, ichthyoplanktons, the natural history and ecology of milkfish, Chanos chanos, milkfish farming in the Philippines, the biology and management of the pest snail Cerithidea cingulata in fishponds, sulfide biochemistry and toxicology, and the early development and behavior of marine fishes. She has authored ~50 publications. She is a writer and the editor of Fish World Matters and AQD Matters. She is currently at the Division of Fishes, c/o Dr. David Smith, National Museum of Natural History, Washington DC, USA

#30: A 'Book' on Every Living Thing Author: adediosLocation: Angel C. de Dios PostPosted: Fri Mar 07, 2008 3:13 pm
A 'Book' on Every Living Thing
Susan Milius

March 5, 2008

Fish that weigh more than a refrigerator. Fish with glowing slime. Fish that look like cows—or at least did to the folks who named them cowfish (and these creatures do have long faces).
Some very odd creatures swim through the world's waters. Now, getting to know them is about to get easier. Beginning last week, a new Web site went live. Called the Encyclopedia of Life (www.eol.org), this online book of life will offer basic facts on about 30,000 species—or kinds—of fish. That's every type known.

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