Nomenclature and placental mammal phylogeny

  title={Nomenclature and placental mammal phylogeny},
  author={Robert J. Asher and Kristofer M. Helgen},
  journal={BMC Evolutionary Biology},
  pages={102 - 102}
An issue arising from recent progress in establishing the placental mammal Tree of Life concerns the nomenclature of high-level clades. Fortunately, there are now several well-supported clades among extant mammals that require unambiguous, stable names. Although the International Code of Zoological Nomenclature does not apply above the Linnean rank of family, and while consensus on the adoption of competing systems of nomenclature does not yet exist, there is a clear, historical basis upon… 

The molecular phylogeny of placental mammals and its application to uncovering signatures of molecular adaptation.

This thesis proposes and applies the use of heterogeneous models to resolve the position of the root of the placental mammal phylogeny and identifies specific molecular adaptations and non-adaptive mechanisms in the mammalia for a set of telomere-associated genes.

High-level systematics of placental mammals: Current status of the problem

It is shown that the fossil record is the only reliable method to test the phylogenetic hypotheses based on the material of the molecular and morphological studies of recent taxa.

Constraints on the timescale of animal evolutionary history

Calibrations for 88 key nodes across the phylogeny of animals, ranging from the root of Metazoa to the last common ancestor of Homo sapiens, are presented, highlighting the importance of identifying crown (not stem) fossils, levels of confidence in their attribution to the crown, current chronostratigraphic precision, the primacy of the host geological formation and asymmetric confidence intervals.

The enigmatic evolutionary relationships of Palaeocene mammals and their relevance for the Tertiary radiation of placental mammals

By building the largest cladistic data matrix to date, this thesis test the relationships of mammals from the earliest Cenozoic, and from the resulting phylogenies, test the hypotheses that the end-Cretaceous mass extinction resulted in an adaptive radiation of placental mammals.

How many species of mammals are there?

The Mammal Diversity Database (MDD) is presented, a digital, publically accessible, and updateable list of all mammalian species, now available online:

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

A phylogenetic tree shows that crown clade Placentalia and placental orders originated after the K-Pg boundary, but phenomic signals overturn molecular signals to show Sundatheria (Dermoptera + Scandentia) as the sister taxon of Primates, a close link between Proboscidea and Sirenia (sea cows), and the monophyly of echolocating Chiroptera (bats).

The International Code of Zoological Nomenclature must be drastically improved before it is too late

It is argued here that if the Code of the 21st century does not evolve to incorporate these changes, it will prove unable to play its role in front of several important recent theoretical and practical developments of taxonomy and run the risk of being abandoned by a part of the international community of zootaxonomists.

A Genomic Approach to Examine the Complex Evolution of Laurasiatherian Mammals

It is shown that the genome evolution of Laurasiatheria may best be understood as an evolutionary network, contrary to the common expectation to resolve major evolutionary events as a bifurcating tree, genome analyses unveil complex speciation processes even in deep mammalian divergences.

Resolving the relationships of Paleocene placental mammals

The largest cladistic analysis of Paleocene placentals to date is presented, from a data matrix including 177 taxa (130 of which are Palaeogene) and 680 morphological characters, and supports an Atlantogenata–Boreoeutheria split at the root of crown Placentalia, the presence of phenacodontids as closest relatives of Perissodactyla, and the validity of Euungulata.

Advantages and Limitations in the Use of Extant Xenarthrans (Mammalia) as Morphological Models for Paleobiological Reconstruction

The limitations of the use of extant xenarthrans as morphological models for paleobiological reconstructions are evaluated and the need to apply other approaches, such as mechanics, that address form-function relationships but are not necessarily based on known biological comparators is suggested.



The new framework for understanding placental mammal evolution

Compared with previous hypotheses this tree is remarkably stable; however, some uncertainty persists about the location of the placental root, and (for example) the position of bats within laurasiatheres, of sea cows and aardvarks within afrotheres, and of dermopterans within euarchontoglires.

Resolution of the Early Placental Mammal Radiation Using Bayesian Phylogenetics

Crown-group Eutheria may have their most recent common ancestry in the Southern Hemisphere (Gondwana), and placental phylogeny is investigated using Bayesian and maximum-likelihood methods and a 16.4-kilobase molecular data set.

Using genomic data to unravel the root of the placental mammal phylogeny.

The genome sequence assemblies of human, armadillo, elephant, and opossum are analyzed to identify informative coding indels that would serve as rare genomic changes to infer early events in placental mammal phylogeny and suggest Afrotheria and Xenarthra diverged from other placental mammals approximately 103 (95-114) million years ago.

A web-database of mammalian morphology and a reanalysis of placental phylogeny

  • R. Asher
  • Biology
    BMC Evolutionary Biology
  • 2006
A graphical web-database of morphological characters focusing on placental mammals, in tandem with a combined-data phylogenetic analysis of placental mammal phylogeny, reinforces the growing consensus regarding the extant placental mammalian clades of Afrotheria, Xenarthra, Euarchontoglires, and Laurasiatheria.

Toward a Phylogenetic Classification of the Mammalia

This short paper attempts to update certain aspects of my previous review by taking into account research published since 1969, as well as work being incorporated into a new classification of the Mammalia now being prepared which wall deal with all taxonomic levels down to the subgeneric level in essentially the same style as Simpson’s (1945) classification.

Major mammalian clades: a review under consideration of molecular and palaeontological evidence

Patterns of comparative disparity and diversity, historical and modern biogeography, and morphological and ecological convergence between and within placental superorders are discussed.


The evolutionary success of mammals is one of the few in evolutionary history for which the authors can offer an explanation, and mode of reproduction, level of metabolism, and an ancestral, generalized quadrupedal stance are offered.

Higher taxonomic relationships among extant mammals based on morphology, with selected comparisons of results from molecular data.

Significant differences between the findings and those of recent investigators include the dissociation of Pholidota from Xenarthra and the plesiomorphous position of Lipotyphla within Epitheria.

Towards resolving the interordinal relationships of placental mammals.

It is shown that progress towards a reliable phylogeny for placental mammals at the ordinal level continues apace, particularly work not incorporated in the remainder of this issue or published elsewhere.