Age of cichlids: new dates for ancient lake fish radiations

Timing divergence events allow us to infer the conditions under which biodiversity has evolved and gain important insights into the mechanisms driving evolution. Cichlid fishes are a model system for studying speciation and adaptive radiation, yet, we have lacked reliable timescales for their evolution. Phylogenetic reconstructions are consistent with cichlid origins prior to Gondwanan landmass fragmentation 121-165 MYA, considerably earlier than the first known fossil cichlids (Eocene). We examined the timing of cichlid evolution using a relaxed molecular clock calibrated with geological estimates for the ages of 1) Gondwanan fragmentation and 2) cichlid fossils. Timescales of cichlid evolution derived from fossil-dated phylogenies of other bony fishes most closely matched those suggested by Gondwanan breakup calibrations, suggesting the Eocene origins and marine dispersal implied by the cichlid fossil record may be due to its incompleteness. Using Gondwanan calibrations, we found accumulation of genetic diversity within the radiating lineages of the African Lakes Malawi, Victoria and Barombi Mbo, and Palaeolake Makgadikgadi began around or after the time of lake basin formation. These calibrations also suggest Lake Tanganyika was colonized independently by the major radiating cichlid tribes that then began to accumulate genetic diversity thereafter. These results contrast with the widely accepted theory that diversification into major lineages took place within the Tanganyika basin. Together, this evidence suggests that ancient lake habitats have played a key role in generating and maintaining diversity within radiating lineages and also that lakes may have captured preexisting cichlid diversity from multiple sources from which adaptive radiations have evolved.

Risk management at board level: a practical guide for board members

isk Management today has moved from being the topic of top level conferences and media discussions to being a permanent issue in the board and top management agenda. Several new directives and regulations in Switzerland, Germany and EU make it obligatory for the firms to have a risk management strategy and transparently disclose the risk management process to their stakeholders. Shareholders, insurance providers, banks, media, analysts, employees, suppliers and other stakeholders expect the board members to be pro-active in knowing the critical risks facing their organization and provide them with a reasonable assurance vis-à-vis the management of those risks. In this environment however, the lack of standards and training opportunities makes this task difficult for board members. This book with the help of real life examples, analysis of drivers, interpretation of the Swiss legal requirements, and information based on international benchmarks tries to reach out to the forward looking leaders of today's businesses. The authors have collectively brought their years of scientific and practical experience in risk management, Swiss law and board memberships together to provide the board members practical solutions in risk management. The desire is that this book will clear the fear regarding risk management from the minds of the company leadership and help them in making risk savvy decisions in quest to achieve their strategic objectives.

Informationsasymmetrien zwischen Übergeber und Nachfolger: Herausforderungen und Lösungsmöglichkeiten am Beispiel des Management Buy Ins in Familienunternehmen

Trotz der steigenden Bedeutung von familienexternen Nachfolgeregelungen wie MBO und MBI bestehen hinsichtlich dieser Nachfolgeoptionen noch große Forschungslücken. Obwohl die Informationsökonomie einen viel versprechenden Ansatz darstellt, um ein fundierteres Verständnis zu erlangen, ist sie in diesem Kontext noch zu wenig angewandt worden. Dies wäre jedoch vor allem in Bezug auf einen MBI sinnvoll, da dort die deutlichsten Informationsasymmetrien zwischen Übergeber und Nachfolger auftreten können. In diesem Beitrag bedienen wir uns daher der Informationsökonomie und analysieren die verschiedenen Informationsasymmetrien bei einem MBI im Detail. Außerdem zeigen wir verschiedene Möglichkeiten auf, wie die entsprechenden Asymmetrien überwunden werden können. Damit leisten wir einen wertvollen Beitrag zu Wissenschaft und Praxis.