Stefan Koenemann – författare

The scientific understanding of arthropod phylogeny and evolution has changed significantly in recent decades. One of the most momentous alterations involved crustaceans, which are not a monophyletc group, but are part of a larger group along with insects: Pancrustacea. The old ideas surrounding crustacean evolution have served scientists well for many years; it is now time to turn toward new research by embracing the results derived from investigations conducted largely within this century. For example, new definitions have arisen from sources across several fields of study, and Frederick R. Schram and Stefan Koenemann have created a book that explores paleobiodiversity and the diversity of modern body plans. Developments within ontogenetic studies continue to generate remarkable insights into crustaceomorph evolution in regard to patterns of embryology and a revolution in the application of development genetics. Phylogeny techniques of analysis and new sources of data derived from molecular sequencing and genetic studies have forced scientists to consider new hypotheses concerning the interrelationships of all the pancrustaceans, both the crustaceomorphs and Hexapoda. Yet, some fossil groups still remain enigmatic (Thylacocephala). Despite this, research into fossils (even if incompletely understood) fills in gaps of our knowledge of paleobiodiversity, and it's useful for many things, including analyzing the origin and early evolution of Hexapoda.Evolution and Phylogeny of Pancrustacea demonstrates the use of multiple alternative hypotheses and other techniques through the well-executed presentation of diverse data sources involving Pancrustacea. Readers are left with clues to great mysteries, including the possible pathways of evolution within marine arthropods.

Recently, technological progress and the rise of DNA barcoding efforts have led to a significant increase in the availability of molecular datasets on intraspecific variability. Carcinologists and other organismal biologists, who want to use molecular tools to investigate patterns on the scale of populations, face a bewildering variety of genetic markers, analytical methods, and computer programs from which to choose. A modern overview of population genetic and phylogeographic studies, Phylogeography and Population Genetics in Crustacea offers insights to guide research on intraspecific genetic variation in crustaceans.Combining theory and case studies of current best practices, the book helps researchers select methods of analysis and interpret their results. The theoretical chapters discuss the potential of currently used and upcoming molecular markers in the context of marine non-model species. They also gather practical tips and address the effect of seldom-discussed sources of error, such as spatial and temporal variation, stochasticity, and choice of statistical parameters. Case studies of marine and limnic crustaceans from around the world highlight the importance and diversity of sources of population structure in intraspecific variation. Written by an international team of 46 leading experts, the book showcases the use and analysis of molecular markers, including mitochondrial and nuclear DNA sequence data, coding and non-coding sequences, microsatellites, and cytogenetics. It gives researchers and students a valuable summary of current knowledge on the processes that shape genetic variability and geographic distribution patterns in space and time.

Compared to other arthropods, crustaceans are characterized by an unparalleled disparity of body plans. Traditionally, the specialization of arthropod segments and appendages into distinct body regions has served as a convenient basis for higher classification; however, many relationships within the phylum Arthropoda still remain controversial.Can Crustacea even be considered a monophyletic group?If so, then which are their closest relatives within the Arthropoda?The answers to questions such as these will play a key role in understanding patterns and processes in arthropod evolution, including the disappearance of certain body plans from the fossil record, as well as incidences of transition from aquatic to terrestrial environments.Crustacea and Arthropod Relationships, written by a team of internationally recognized experts, presents a wide variety of viewpoints, while offering an up-to-date summary of recent progress across several disciplines. With rich detail and vibrancy, it addresses the evolution and phylogenetic relationships of the Arthropoda based upon molecular, developmental, morphological, and paleontological evidence.Volume 16 is the first in the series to not be exclusively dedicated to discussions specific to crustaceans. While it is still crustaceo-centric, the focus of this volume has been extended to include other groups of arthropods along with the Crustacea. This wider focus offers challenging opportunities to evaluate higher-level relationships within the Arthropoda from a carcinologic perspective.This volume is dedicated to the career of Frederick R. Schram, the founding editor of CrustaceanIssues in 1983, in recognition of his many stimulating and wide-ranging contributions to the evolutionary biology of arthropods in general, and of crustaceans in particular.

Compared to other arthropods, crustaceans are characterized by an unparalleled disparity of body plans. Traditionally, the specialization of arthropod segments and appendages into distinct body regions has served as a convenient basis for higher classification; however, many relationships within the phylum Arthropoda still remain controversial.Can Crustacea even be considered a monophyletic group?If so, then which are their closest relatives within the Arthropoda?The answers to questions such as these will play a key role in understanding patterns and processes in arthropod evolution, including the disappearance of certain body plans from the fossil record, as well as incidences of transition from aquatic to terrestrial environments.Crustacea and Arthropod Relationships, written by a team of internationally recognized experts, presents a wide variety of viewpoints, while offering an up-to-date summary of recent progress across several disciplines. With rich detail and vibrancy, it addresses the evolution and phylogenetic relationships of the Arthropoda based upon molecular, developmental, morphological, and paleontological evidence.Volume 16 is the first in the series to not be exclusively dedicated to discussions specific to crustaceans. While it is still crustaceo-centric, the focus of this volume has been extended to include other groups of arthropods along with the Crustacea. This wider focus offers challenging opportunities to evaluate higher-level relationships within the Arthropoda from a carcinologic perspective.This volume is dedicated to the career of Frederick R. Schram, the founding editor of CrustaceanIssues in 1983, in recognition of his many stimulating and wide-ranging contributions to the evolutionary biology of arthropods in general, and of crustaceans in particular.