Discover the history of the brave settlers who faced and survived innumerable hardships in the unforgiving St. Croix River Valley.

Sex is the queen of problems in evolutionary biology. Generations of researchers have investigated one of the last remaining evolutionary paradoxes: why sex exists at all. Given that sexual reproduction is costly from an evolutionary point of view, one could wonder why not all animals and plants reproduce asexually. Dozens of contemporary hypotheses attempt to explain the prevalence of sex and its advantages and predict the early extinction of fully asexual lineages. The major theme of this book is: what is the fate of animal and plant groups in which sex is lost? Initial chapters discuss theory behind asexual life: what major disadvantages do asexual groups have to face, what are the genetic and ecological consequences and what does this theory predict for more applied aspects of asexual life, for example in agricultural pests, diseases as well as in cultural crops such as grapes. Cases studies in many animals (focusing on both invertebrates and vertebrates) and plants reveal parallel, but also singularly novel adaptations to the absence of meiosis and syngamy. And last but not least, are asexuals really doomed to early extinction or do genuine ancient asexuals exist? This book assembles contributions from the most important research groups dealing with asexual evolution in eukaryotes. It is a milestone in research on parthenogenesis and will be useful to undergraduate as well as graduate students and to senior researchers in all fields of evolutionary biology, as the paradox of sex remains its queen of problems.

Sex is the queen of problems in evolutionary biology. Generations of researchers have investigated one of the last remaining evolutionary paradoxes: why sex exists at all. Given that sexual reproduction is costly from an evolutionary point of view, one could wonder why not all animals and plants reproduce asexually. Dozens of contemporary hypotheses attempt to explain the prevalence of sex and its advantages and predict the early extinction of fully asexual lineages. The major theme of this book is: what is the fate of animal and plant groups in which sex is lost? Initial chapters discuss theory behind asexual life: what major disadvantages do asexual groups have to face, what are the genetic and ecological consequences and what does this theory predict for more applied aspects of asexual life, for example in agricultural pests, diseases as well as in cultural crops such as grapes. Cases studies in many animals (focusing on both invertebrates and vertebrates) and plants reveal parallel, but also singularly novel adaptations to the absence of meiosis and syngamy. And last but not least, are asexuals really doomed to early extinction or do genuine ancient asexuals exist? This book assembles contributions from the most important research groups dealing with asexual evolution in eukaryotes. It is a milestone in research on parthenogenesis and will be useful to undergraduate as well as graduate students and to senior researchers in all fields of evolutionary biology, as the paradox of sex remains its queen of problems. Written for: All who are interested in parthenogenesis and evolutionary biology, including undergraduate and graduate students and senior researchers

Ostracoda (Crustacea) are potentially excellent model organisms for evolutionary studies, because they combine an extensive fossil record with a wide recent distribution and therefore allow studies on both patterns and processes leading to extant diversity. The main scientific domains contributing theories, concepts, and data to evolutionary biology are morphology (including ontogeny), palaeontology, genetics, and ecology, and to all of these aspects ostracods can contribute. This is clearly illustrated by the fifteen papers presented under Theme 3 of the 13th International Symposium on Ostracoda (Chatham, UK) in 1997 which are grouped in the present proceedings, one of three volumes resulting from this meeting. The contributions deal with the evolution of both extant and fossil forms (including most of the Phanaerozoic), ecology of both marine and freshwater taxa, and (developmental) morphology of both soft parts and valves. Although the canvas is wide, each paper clearly shows how studies on Ostracoda can be relevant to general theory on evolutionary biology and ecology.