Algal ecotypes: what they are and what they are not

A salt tolerant ecotype of Scenedesmus armatus from the Baltic Sea is reported. Salinity treatments also reveal variable plasticity of several morphological features of this alga The problem of drawing a sharp distinction between stable and plastic attributes is discussed and it is concluded that the terms ecotype and ecophene, as originally defined, are no longer applicable to algae. A redefinition of the ecotype is proposed.     

Inarticulate they are not!

Popov, L. & Holmer, L.E. 1994 Cambrian-Ordovician lingulate brachio-pods from Scandinavia, Kazakhstan, and South Ural Mountains. Fossils and Strata , No. 35,156 pp. and 115 figures.     

Predators are rare even when they are small

A recent review of published studies revealed that predators generally have lower population densities than non-predators in a variety of communities. We report here similar results for a highly replicated study of macroinvertebrates that colonized very uniform detrital microcosms in an old field. This pattern persisted even though predators usually were smaller than non-predators, as determined by body length and volume.     

Membrane lipids: where they are and how they behave

Throughout the biological world, a 30 A hydrophobic film typically delimits the environments that serve as the margin between life and death for individual cells. Biochemical and biophysical findings have provided a detailed model of the composition and structure of membranes, which includes levels of dynamic organization both across the lipid bilayer (lipid asymmetry) and in the lateral dimension (lipid domains) of membranes. How do cells apply anabolic and catabolic enzymes, translocases and transporters, plus the intrinsic physical phase behaviour of lipids and their interactions with membrane proteins, to create the unique compositions and multiple functionalities of their individual membranes?     

Synthetic fuels: what are they and where do they come from?

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The evolution of creationists in the United States: Where are they now,and where are they going?

The history of anti-evolutionism in the United States begins only in the early decades of the 20th century but has evolved considerably since then. Various versions of the movement (“equal time” for creationism, “creation science”, “intelligent design”) have developed over time, but they have made few positive contributions to serious discourse about science and religion. Their main goal has been to try to stop the teaching of evolution. The most recent version of creationism, “intelligent design” (ID), has little in common with William Paley's 18th-century version: ID posits an interventionist Deity who regularly interferes in natural processes to produce complex biological structures and functions. The 2005 “intelligent design” trial in Dover, Pennsylvania, destroyed any pretensions that the movement had to scientific integrity. However, anti-evolutionists continue to foment discord at local levels, where opposition to the teaching of evolution can be presented without strong resistance. Scientists can best demonstrate their concern by becoming involved in federal, state, and local administrative processes that determine curricula and develop and adopt textbooks and other instructional materials. To cite this article: K. Padian, C. R. Biologies 332 (2009).     

Trees are rarely most abundant where they grow best

Aims A common assumption in ecology is that where a species is found to be most abundant must correspond to the environmental context in which the species performs the best (i.e. optimal niche space). This assumption is central to common conservation and management tools such as habitat suitability assessment and species distribution modeling. I test this hypothesis.Methods I use the US Forest Inventory Assessment data for the abundance of trees across eastern North America. I use the FORAST tree-ring dataset for ontogenetic growth rate (tree-ring increment), a measure of niche performance and correlated with intrinsic rate of increase, r .Important findings I find that across 15 species, there are significantly more negative correlations than expected by chance. This negative correlation between abundance and performance across space contradicts common assumptions but is consistent with an inclusive niche structuring of the community.