Christoph Scheidegger

Bio: Christoph Scheidegger is an academic researcher from Swiss Federal Institute for Forest, Snow and Landscape Research. The author has contributed to research in topics: Lobaria pulmonaria & Lichen. The author has an hindex of 45, co-authored 194 publications receiving 6910 citations. Previous affiliations of Christoph Scheidegger include University of Bern & University of California, Santa Barbara.

Pcr primers for the amplification of mitochondrial small subunit ribosomal dna of lichen-forming ascomycetes

Abstract: Four primers for the amplification of mitochondrial DNA of lichen-forming ascomycetes are presented. The primers match the conserved regions U2, U4, and U6, respectively, of mitochondrial small subunit (SSU) ribosomal DNA (rDNA). Polymerase chain reaction using different combinations of the primers produced single amplification products from DNA of eight lichen-forming fungal species but did not amplify DNA of two axenic cultured algal species. The amplification product obtained from Lobaria pulmonaria was sequenced and the 894-bp sequence was compared with the mitochondrial SSU rDNA sequence of Podospora anserina. The two sequences revealed more than 76% identity in the conserved regions U3 to U5 demonstrating that we amplified mitochondrial DNA. The primers matching U2 and U6 yielded amplification products of 800–1000 bp depending on the species examined. The variation observed suggests that mitochondrial SSU rDNA may be useful for phylogenetic analyses of lichen-forming ascomycetes.

Monitoring with Lichens — Monitoring Lichens

Abstract: Widespread changes in natural and managed environments in the last century have been associated with rapid development of technology with the capacity for massive destruction of natural environments. This has been accompanied by large-scale natural disasters such as floods and droughts and by large-scale technical failures such as Chernobyl, impacting greatly on human existence and welfare. It is the impact on social conditions that has led to increasing interest in maintaining environmental quality and ensuring that human activities do not threaten the ecosystem on which we depend. The threats to human health by water and air pollution led to early research on bioindicators in order to map and monitor the effects of pollution on selected organisms. However the range of objectives to which biomonitoring is applied has grown steadily from water quality and atmospheric pollution to heavy metal accumulation, climate change, and to environmental issues involving management of natural resources such as the effects of fragmentation and habitat alteration, effects of development on biodiversity as well as assessing conservation practices for rare or endangered species.

A five-gene phylogeny of Pezizomycotina

Abstract: Pezizomycotina is the largest subphylum of Ascomycota and includes the vast majority of filamen- tous, ascoma-producing species. Here we report the results from weighted parsimony, maximum likelihood and Bayesian phylogenetic analyses of five nuclear loci (SSU rDNA, LSU rDNA, RPB1, RPB2 and EF-1a) from 191 taxa. Nine of the 10 Pezizomycotina classes currently recognized were represented in the sam- pling. These data strongly supported the monophyly of Pezizomycotina, Arthoniomycetes, Eurotiomycetes, Orbiliomycetes and Sordariomycetes. Pezizomycetes and Dothideomycetes also were resolved as mono- phyletic but not strongly supported by the data. Lecanoromycetes was resolved as paraphyletic in parsimony analyses but monophyletic in maximum likelihood and Bayesian analyses. Leotiomycetes was polyphyletic due to exclusion of Geoglossaceae. The two most basal classes of Pezizomycotina were Orbilio- mycetes and Pezizomycetes, both of which comprise species that produce apothecial ascomata. The seven

New insights into classification and evolution of the Lecanoromycetes (Pezizomycotina, Ascomycota) from phylogenetic analyses of three ribosomal RNA- and two protein-coding genes

Abstract: The Lecanoromycetes includes most of the lichen-forming fungal species (>13 500) and is therefore one of the most diverse class of all Fungi in terms of phenotypic complexity. We report phylogeneti...

Mapping lichen diversity as an indicator of environmental quality

Abstract: In the last decades, several methods were proposed for assessing environmental quality — mainly air pollution — on the basis of lichen data (see chapter 4, this volume). At the end of the 80s the predictivity of 20 different methods with respect to instrumental pollution data was tested in Switzerland using multiple regression [1, 5]. The highest correlation was found with the sum of frequencies of lichen species within a sampling grid of 10 units positioned on the trunks of free-standing trees. This method was immediately and widely adopted in several other countries, esp. Italy and Germany, with some modifications, chiefly concerning the size of the sampling grid. Since 1987, hundreds of studies were carried out with this approach, which led to its standardization in the form of guidelines both in Germany [13], and in Italy [7].

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

The Theory of Island Biogeography

Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

Human biochemical genetics

Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to