In this study we investigated the phylogenetic relationships within the ‘higher land birds’ by parsimony analysis of nucleotide DNA sequences obtained from the two nuclear, protein‐coding genes, c‐myc and RAG‐1. Nuclear genes have not previously been used to address this phylogenetic question. The results include high jackknife support for a monophyletic Apodiformes (including the Trochilidae). This arrangement was further supported by the observation of an insertion of four amino acids in the c‐myc gene in all apodiform taxa. Monophyly was also inferred for each of the two piciform groups Galbulae and Pici. Within Pici, the Capitonidae was found to be paraphyletic, with the New World barbets more closely related to the Ramphastidae than to the Old World barbets. Another clade with high jackknife support consists of the Upupidae, Phoeniculidae and Bucerotidae. The families Momotidae and Todidae, and Coraciidae and Brachypteraciidae, respectively, also form well supported monophyletic clades. The results are inconclusive regarding the monophyly of the orders Coraciiformes and Piciformes, respectively.
Despite significant, steady improvements in the skill of medium-range weather predictionsystems over the past several decades, the accuracy of these forecasts are occasionally very poor.These forecast failures are referred to as “busts” or “dropouts”. The lack of a clear explanationfor bust events limits the development and implementation of strategies designed to reduce theiroccurrence. This study seeks to explore a flow regime where forecast busts occur over Europe inassociation with mesoscale convective systems over North America east of the Rocky Mountains.Our investigation focuses on error growth in the European Centre for Medium-Range WeatherForecasting’s (ECMWF’s) global model during the summer 2015 PECAN (Plains Elevated Convectionat Night) experiment. Observations suggest that a close, but varied interrelationship can occurbetween long-lived, propagating, mesoscale convection systems over the Great Plains and Rossbywave packets. Aloft, the initial error occurs in the ridge of the wave and then propagates downstreamas an amplifying Rossby wave packet producing poor forecasts in middle latitudes and, in somecases, the Arctic. Our results suggest the importance of improving the representation of organizeddeep convection in numerical models, particularly for long-lived mesoscale convective systems thatproduce severe weather and propagate near the jet stream.
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