Allometry and size in ontogeny and phylogeny.

Biologists often compare average phenotypes of groups of species defined cladistically or on behavioral, ecological, or physiological criteria (e.g., carnivores vs. herbivores, social vs. nonsocial species, endotherms vs. ectotherms). Hypothesis testing typically is accomplished via analysis of variance (ANOVA) or covariance (ANCOVA; often with body size as a covariate). Because of the hierarchical nature of phylogenetic descent, however, species may not represent statistically independent data points, degrees of freedom may be inflated, and significance levels derived from conventional tests cannot be trusted. As one solution to this degrees of freedom problem, we propose using empirically scaled computer simulation models of continuous traits evolving along «known» phylogenetic trees to obtain null distributions of F statistics for ANCOVA of comparative data sets

Phylogenetic Analysis of Covariance by Computer Simulation

To discover interordinal relationships of living and fossil placental mammals and the time of origin of placentals relative to the Cretaceous-Paleogene (K-Pg) boundary, we scored 4541 phenomic characters de novo for 86 fossil and living species. Combining these data with molecular sequences, we obtained a phylogenetic tree that, when calibrated with fossils, shows that crown clade Placentalia and placental orders originated after the K-Pg boundary. Many nodes discovered using molecular data are upheld, but phenomic signals overturn molecular signals to show Sundatheria (Dermoptera + Scandentia) as the sister taxon of Primates, a close link between Proboscidea (elephants) and Sirenia (sea cows), and the monophyly of echolocating Chiroptera (bats). Our tree suggests that Placentalia first split into Xenarthra and Epitheria; extinct New World species are the oldest members of Afrotheria.

http://science.sciencemag.org/content/sci/339/6120/662.full.pdf

The Placental Mammal Ancestor and the Post–K-Pg Radiation of Placentals

The origin of the domestic dog from wolves has been established, but the number of founding events, as well as where and when these occurred, is not known. To address these questions, we examined the mitochondrial DNA (mtDNA) sequence variation among 654 domestic dogs representing all major dog populations worldwide. Although our data indicate several maternal origins from wolf, >95% of all sequences belonged to three phylogenetic groups universally represented at similar frequencies, suggesting a common origin from a single gene pool for all dog populations. A larger genetic variation in East Asia than in other regions and the pattern of phylogeographic variation suggest an East Asian origin for the domestic dog, ∼15,000 years ago.

/pdf/genetic-evidence-for-an-east-asian-origin-of-domestic-dogs-2qsg7spbj5.pdf

Genetic Evidence for an East Asian Origin of Domestic Dogs

Between fifty and ten thousand years ago, most large mammals became extinct everywhere except Africa. Slow-breeding animals also were hard hit, regardless of size. This unusual extinction of large and slow-breeding animals provides some of the strongest support for a human contribution to their extinction and is consistent with various human hunting models, but it is difficult to explain by models relying solely on environmental change. It is an oversimplification, however, to say that a wave of hunting-induced extinctions swept continents immediately after first human contact. Results from recent studies suggest that humans precipitated extinction in many parts of the globe through combined direct (hunting) and perhaps indirect (competition, habitat alteration) impacts, but that the timing and geography of extinction might have been different and the worldwide magnitude less, had not climatic change coincided with human impacts in many places.

/pdf/late-quaternary-extinctions-state-of-the-debate-1f8rigowiq.pdf

Late Quaternary Extinctions: State of the Debate

Pleistocene Mammals of North America

This book provides a comprehensive treatment of all the Pleistocene species in Europe, classified according to modern taxonomic principles. For each species there is a description of its descent and migration history, its range, and its mode of life. The first version of this book was a semipopular paperback in the Swedish Aldus series.

Pleistocene Mammals of Europe

This portrait of the cave bear conveys facts about this animal, including its structure, habits, and society, the Ice Age environment, sexual and racial variations, and extinction. The text also details the relationship between man and bear, and theories surrounding bear-hunting and bear cults.

Bjorn Kurten

Papers

Pleistocene Mammals of North America

Pleistocene Mammals of Europe

The Cave Bear Story: Life and Death of a Vanished Animal

The age of mammals

Pleistocene Mammals of Europe.