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Archive for February, 2007

EcoRes Forum Launches Climate Change E-Conference Series

Wednesday, February 28th, 2007

I wish to draw your attention to a series of e-conferences on climate change.

18 January 2007 – The EcoRes Forum, a new initiative undertaken by Mary Leyser, Coordinator of the Eco-Ethics International Union (EEIU), and Acad. Prof. Gennady Polikarpov, EEIU Vice-President and Chief Scientist at the
Institute of Biology of Southern Seas in Sevastopol, Ukraine, announces the launch of a series of online e-conferences focusing on the ethical, political and sociocultural aspects of climate change.

The series, which will be offered free of charge, starts off in April 2007 with a two-week dialogue on a topic of increasing urgency: expanding and accelerating an ecocentric philosophy among societies around the world. The need for such a shift has long been recognized. Based on the UN’s Rio Declaration of Environment and Development, in 1992 Al Gore observed, “Our challenge is to accelerate the needed change in thinking about our relationship to the environment in order to shift the pattern of our civilization to a new equilibrium – before the world’s ecological system loses its current one.” (Earth in the Balance)

Titled “From Anthropocentrism to Ecocentrism: Making the Shift”, the e-conference will bring together academics and activists, scientists and social critics, researchers and journalists, community leaders and citizens, all focused on looking for answers and actions to make this paradigm shift a reality. After reflecting on past movement successes to identify transferable practices, the semi-structured discussion will evaluate the current status – looking at what is working (and what isn’t) around the globe. Armed with this knowledge, participants will shift focus to the
future, considering multi-prong approaches for moving forward on this trans-disciplinary issue.

As EcoRes materials outline, the forum’s mission is ambitious, yet,organizers are convinced, fully achievable:

In keeping with our foundational philosophy of ecocentric environmental ethics and commitment to the principles of social equity and environmental justice;

  • by leveraging the potential of new media by providing an easily accessible global platform for discussion and access to subject experts;
  • by involving global stakeholders in global issue discussions by circumventing the logistical and financial barriers of traditional dialogue interactions;
  • by building ongoing connections and networks between these actors;
  • by crossing borders, whether disciplinary, philosophical, or geopolitical; and
  • by maintaining a results-oriented focus;

the goals of the EcoRes Forum are:

  • to level the field of discourse by moving it to a space whose boundaries are set only by our own creativity;
  • to promote awareness, public dialogue and the free exchange and exploration of ideas, knowledge and issues related to climate change;
  • to leave all participants with something of value, whether knowledge, best practices, or a new perspective, which can be put to use immediately to improve efforts in their individual fields; and
  • by so doing, to contribute to taking the environmental movement to the next level and thereby, in some small way, to assist in preventing further extreme human-induced climate change.

For more information or to register for the April event, visit the EcoRes Forum website at http://www.eco-res.org or write forum@eco-res.org.

Why are there so many species in the tropics? Effective evolutionary time

Saturday, February 24th, 2007

Tropical habitats, generally, have many more species than temperate and cold habitats. Such gradients are referred to as latitudinal gradients in species diversity. No agreement has been reached on the causes of the gradients. The hypothesis of effective evolutionary time (K. Rohde: Latitudinal gradients in species diversity: the search for the primary cause, Oikos, 65, 514-527,1992) attempts to explain diversity gradients, and in particular latitudinal gradients. It was originally named “time hypothesis” (K. Rohde: Latitudinal gradients in species diversity and their causes. I. A review of the hypotheses explaining the gradients. Biologisches Zentralblatt 97, 393-403, 1978, K. Rohde: Latitudinal gradients in species diversity and their causes. II. Marine parasitological evidence for a time hypothesis. Biologisches Zentralblatt 97, 405-418, 1978).

Background

Low (warm) latitudes contain significantly more species than high (cold) latitudes. This has been shown for many animal and plant groups, although exceptions exist. An example of an exception is helminths (parasitic worms) of marine mammals, which have the greatest diversity in northern temperate seas, possibly because of small population densities of hosts in tropical seas that prevented the evolution of a rich helminth fauna, or because they originated in temperate seas and had more time for speciation there. It has become more and more apparent that species diversity is best correlated with environmental temperature and more generally environmental energy. These findings are the basis of the hypothesis of effective evolutionary time. Species have accumulated fastest in areas where temperatures are highest. Mutation rates and speed of selection due to faster physiological rates are highest, and generation times which also determine speed of selection, are smallest at high temperatures. This leads to a faster accumulation of species, which are absorbed into the abundantly available vacant niches, in the tropics. Vacant niches are available at all latitudes, and differences in the number of such niches can therefore not be the limiting factor for species richness.

The hypothesis of effective evolutionary time offers a causal explanation of diversity gradients, although it is recognized that many other factors can also contribute to and modulate them.

Historical aspects

Some aspects of the hypothesis are based on earlier studies. (B. Rensch: Neuere Probleme der Abstammungslehre. Die transspezifische Evolution. Encke, Stuttgart, 1954), for example, stated that evolutionary rates also depend on temperature: numbers of generation in poikilotherms, but sometimes also in homoiotherms, are greater at higher temperatures and the effectiveness of selection is therefore greater. Ricklefs refers to this hypothesis as “hypothesis of evolutionary speed“ oder “higher speciation rates“ (E. Ricklefs: Ecology. Nelson and Sons, London, 1973). Genera of Foraminifera in the Cretacious and families of Brachiopoda in the Permian have greater evolutionary rates at low than at high latitudes (F.G. Stehli, E.G. Douglas and N.D. Newell: Generation and maintenance of gradients in taxonomic diversity. Science 164, 947-949, 1969). That mutation rates are greater at high temperatures has been known since the classical investigations of N.W. Timofeeff-Ressovsky, K.G. Zimmer und M. Delbrück: Über die Natur der Genmutation und der Genstruktur. Nachrichten aus der Biologie der Gesellschaft der Wissenschaften Göttingen I, 189-245, 1935), although few later studies have been conducted. Also, these findings were not applied to evolutionary problems.

The hypothesis of effective evolutionary time differs from these earlier approaches as follows. It proposes that species diversity is a direct consequence of temperature-dependent processes and the time ecosystems have existed under more or less equal conditions. Since vacant niches into which new species can be absorbed are available at all latitudes, the consequence is accumulation of more species at low latitudes. All earlier approaches remained without basis without the assumption of vacant niches, as there is no evidence that niches are generally narrower in the tropics, i.e., an accumulation of species cannot be explained by subdivision of previously utilized niches. The hypothesis, in contrast to most other hypotheses attempting to explain latitudinal or other gradients in diversity, does not rely on the assumption that different latitudes or habitats generally have different “ceilings” for species numbers, which are higher in the tropics than in cold environments. Such different ceilings are thought to be, for example, determined by heterogeneity or area of the habitat. But such factors, although not setting ceilings, may well modulate the gradients.

A considerable number of recent studies, discussed in K. Rohde: Nonequilibrium Ecology, Cambridge University Press, Cambridge, 2005b, 223 pp., http://www.cambridge.org/9780521674553 support the hypothesis. Thus, diversity of marine benthos, interrupted by some collapses and plateaus, has risen from the Cambrian to the Recent, and there is no evidence that saturation has been reached (D.Jablonski: The future of the fossil record, Science 284, 2114-2116, 1999). Rates of diversification per time unit for birds and butterflies increase towards the tropics (M. Cardillo: Latitude and rates of diversification in birds and butterflies. Proceedings of the Royal Society London 266, 1221-1225,1999). Allen et al. found a general correlation between environmental temperature and species richness for North and Central American trees, for amphibians, fish, Prosobranchia and fish parasites. They showed that species richness can be predicted from the biochemical kinetics of metabolism, and concluded that evolutionary rates are determined by generation times and mutation rates both correlated with metabolic rates which have the same Boltzmann relation with temperature. They further concluded that these findings support the mechanisms for latitudinal gradients proposed by Rohde (A.P. Allen, J.H. Brown, and J.F. Gillooly: Global biodiversity, biochemical kinetics, and the energetic-equivalence rule. Science, 297, 1545-1548, 2002). Gillooly et al. (2002) described a general model also based on first principles of allometry and biochemical kinetics which makes predictions about generation times as a function of body size and temperature (J.F. Gillooly, E.L. Charnov, G.B. West, M.Van Savage, and J.H. Brown: Effects of size and temperature on developmental time. Nature 417, 70–73, 2002). Empirical findings support the predictions: in all cases that were investigated (birds, fish, amphibians, aquatic insects, zooplankton) generation times are negatively correlated with temperature. Brown et al.(2004) further developed these findings to a general metabolic theory of ecology (J.H. Brown, J.F. Gillooly, A.P. Allen, M. Van Savage, and G.. West,. (2004). Toward a metabolic theory of ecology. Ecology 85, 1771-1789). Indirect evidence points to increased mutation rates at higher temperatures (C. Bazin, P. Capy, D. Higuet, and T. Langin, T.: Séquences d’AND mobiles et évolution du génome. Pour Sci., Hors. Sér. Janvier 97, 106-109., 1997), and the energy-speciation hypothesis is the best predictor for species richness of ants (M. Kaspari, P.S. Ward and M.Yuan: Energy gradients and the geographical distribution of local ant diversity. Oecologia 140, 407-413, 2004). Finally, computer simulations using the Chowdhury eosystem model have shown that results correspond most closely to empirical data when the number of vacant niches is kept large (K. Rohde and D. Stauffer: “Simulation of geographical trends in Chowdhury ecosystem model”, Advances in Complex Systems 8, 451-464, 2005). For a detailed discussion of these and other examples see K. Rohde: Nonequilibrium Ecology, Cambridge University Press, Cambridge, 2005b, 223 pp., http://www.cambridge.org/9780521674553 and K. Rohde: Eine neue Ökologie. Aktuelle Probleme der evolutionären Ökologie”. Naturwissenschaftliche Rundschau, 58, 420-426, 2005.

Depth gradients

Species diversity in the deepsea has been largely underestimated until recently (e.g., Briggs 1994: total marine diversity less than 200,000 species) (J. C.Briggs. Species diversity: land and sea compared. Systematic Biology 43, 130-135, 1994). Although our knowledge is still very fragmentary, some recent studies appear to suggest much greater species numbers (e.g., Grassle and Maciolek 1992: 10 million macroinvertebrates in soft bottom sediments of the deepsea) (J. F. Grassle and N. J. Maciolek: Deepsea species richness: regional and local diversity estimates from, quantitative bottom samples. American Naturalist 139, 313-341, 1992). Further studies must show whether this can be verified (K. Rohde: Ecology and biogeography of marine parasites. Advances in marine biology 43,1-86, 2002). A rich diversity in the deepsea can be explained by the hypothesis of effective evolutionary time: although temperatures are low, conditions have been more or less equal over large time spans, certainly much larger than in most or all surface waters.

This post is based on an earlier article of mine in Wikipedia. See also post on vacant niches.

Review of Nonequilibrium Ecology

Saturday, February 24th, 2007

Here are extracts from the first review, by a distinguished ecologist, of my book Nonequilibrium Ecology (http://www.cambridge.org/9780521674553). The reviewer is well known for his studies of coral fish communities.

Book Reviews
Parasites and Passerines Tell Different Tales
Nonequilibrium Ecology. Rohde,
K. 2006. Cambridge University Press,
New York, NY. 234 (xi + 223) pp.
$120.00 (hardcover). ISBN 0-521-
85434-2. $60.00 (paperback). ISBN 0-
521-67455-7.
Passerine birds have had a surprisingly substantial impact on the development of ecological theory. Studies of birds, most often passerines, have been central to such topics as niche theory, resource partitioning, energy allocation, and optimality, and to the broad range of behavioral ecology topics such as parental investment, parent-offspring conflicts, and sexy sons. They have been important despite being a relatively species poor and ecologically atypical taxon. Passerines have strongly determinate growth; thus, juveniles are essentially full size at fledging, and individuals of a species are remarkably uniform in size. Consequently, each bird in a population has a very uniform set of ecological requirements and set of impacts on its environment, and these features remain largely constant throughout life. Passerines are among the less fecund organisms and provide much larger parental investments per offspring than is the case for any animals other than mammals. Passerines are homeotherms with high metabolic rates, and, perhaps because the requirements of flight limit their ability to store energy, they require a continuous supply of food and can quickly die in its absence. Finally, with the forelimbs specialized for flying and the hind limbs for perching, they are forced to use a quite inflexible jaw structure as the sole tool for food acquisition, manipulation, and consumption. In each of these aspects they are bizarre compared with the majority of organisms. In fact, as someone who does not work with birds, I marvel that they have been able to persist and diversify to the extent that they have. Intelligent design would never have produced such creatures—they are so tightly constrained by their morphology, ontogeny, and physiology that they must live continuously at the very edge of survival. It has always seemed strange to me that ecological ideas have been so heavily influenced by such atypical organisms. But then, some of the ideas central to ecological thinking have also seemed very strange to me, and maybe these two things are linked. Perhaps what is termed conventional ecology, or equilibrium ecology to use Rohde’s terminology, got that way because of the strange organisms that fueled its development. In his book Nonequilibrium Ecology, Klaus Rohde sets out to redress both issues. The author provides abundant examples from the ecology of parasites and other organisms to demonstrate that what may possibly be true for some birds is not necessarily the norm for other kinds of creatures. As its title states, the book is also an attempt to draw attention to the very considerable evidence for the idea that ecological systems—populations, communities, ecosystems—are normally (usually) not at or moving toward equilibrial conditions. In my opinion, a book like this has been needed for some time, and I am pleased that Rohde has written it.

……for those students and scientists who value hypotheses and the rigorous testing of them, it is clear that the equilibrium ecology that Rohde argues against is now but a tattered remnant of its earlier sparkling comprehensiveness. …Rohde’s book provides them with substantial ammunition to use in building a new, more realistic ecological paradigm.

……this is a useful book that should be read by any ecologist and particularly by any graduate student interested in a refreshingly different perspective on our science than the one dished up too frequently in survey courses and the conservation press.

Peter F. Sale
Biological Sciences, University of Windsor, Ontario, Canada, and United Nations University—International Network on Water, Environment and Health, Hamilton, Ontario P0B 1J0.

Conservation Biology 21, 282, February 2007

Free market economy

Monday, February 5th, 2007

The hobby horses of neoliberalism: free markets and economic equilibrium. Here they are: the larger swallows the smaller, until everything, rather fast, has reached an equilibrium. In a nutshell, the largest survives, until he is in equilibrium with himself.

marktok.jpg

But it may not always go smoothly. The digestion may not work as expected:

gier.jpg gier3.jpg

But take it cum grano salis: I am not an economist.

From my book “Satire, Politik und Kunst”, Lulu 2006 http://www.lulu.com/content/378808

An artist’s view of global warming and its consequences

Thursday, February 1st, 2007

Here I want to demonstrate that scientists can be funny too (I hope), even on serious matters. An extract from my book ” Satire, Politik und Kunst”, Lulu, 2006. http://www.lulu.com/content/378808
It is getting hot, and the world is exploding around them. She to him: “do something about it”.
overawed.jpg

He: I was a fool, too late.

intdesign.jpg

Global warming and scientific integrity

Thursday, February 1st, 2007

Global warming, much or all of it man induced, is a certainty, and its likely consequences are disastrous. Pressure of governments on scientists to withhold the facts from the public are therefore particularly dangerous. Below some recent information on this point.

BY J. SCOTT ORR
STAR-LEDGER WASHINGTON BUREAU

WASHINGTON — A leading scientist told a House committee yesterday that “political interference is harming federal science and threatening the health and safety of Americans,” and the committee chairman said the Bush White House has been misleading the public on the dangers of global warming.

“Political interference with the work of federal scientists threatens the quality and integrity of (federal) policies,” said Francesca Grifo, director of the Union of Concerned Scientists’ Scientific Integrity Program.

According to a UCS survey whose findings were presented to the House Oversight and Government Reform Committee, more than 40 percent of the 279 scientists who responded said their work had been edited to more closely reflect the administration’s position on climate change.

“No scientist should ever encounter any of the various types of political interference described in our survey questions,” Grifo told the committee, which is looking at the government’s response to climate change.

The panel chairman, Rep. Henry Waxman (D-Calif.), said he has seen evidence the administration has been trying to mislead the public on global warming.

“We know that the White House possesses documents that contain evidence of an attempt by senior administration officials to mislead the public by injecting doubt into the science of global warming and minimizing the potential dangers,” he said.

Waxman demanded that the documents be turned over to his committee. He said he has been rebuffed in his efforts so far.

“The committee isn’t trying to obtain state secrets or documents that could affect our immediate national security. We are simply seeking answers to whether the White House’s political staff is inappropriately censoring impartial government scientists,” he said.

Most scientists believe global warming is caused by greenhouse gases, like carbon dioxide from vehicles and industrial sources, that keep heat from the sun trapped in the atmosphere.

President Bush acknowledged the existence of climate change in his Jan. 23 State of the Union address, though he did not use the term “global warming.”

(downloaded January 31, 2007)

According to the Sydney Morning Herald, February 3, 2007, the American Enterprise Institute, financed by large American oil companies, has offered bribes to scientists to discredit the reliability of the recent UN climate change report, compiled by a large number of scientists from around the world.