To reduce the accelerating rate of phylogenetic diversity loss, many studies have searched for mechanisms that could explain why certain species are at risk, whereas others are not. In particular, it has been demonstrated that species might be affected by both extrinsic threat factors as well as intrinsic biological traits that could render a species more sensitive to extinction; here, we focus...

On the basis of culture studies, Archaea were thought to be synonymous with extreme environments. However, the large numbers of environmental rRNA gene sequences currently flooding into databases such as GenBank show that these organisms are present in almost all environments examined to date. Large sequence databases and new fast phylogenetic software allow more precise determination of the ar...

Given an edge-weighted tree T with leaf set X, define the weight of a subset S of X as the sum of the edge-weights of the minimal subtree of T connecting the elements in S. It is known that the problem of selecting subsets of X of a given size to maximize this weight can be solved using a greedy algorithm. This optimization problem arises in conservation biology where the weight is referred to ...

There is a natural way to associate to any tree T with leaf set X , and with edges weighted by elements from an abelian group G, a map from the power set of X into G — simply add the elements on the edges that connect the leaves in that subset. This map has been wellstudied in the case where G has no elements of order 2 (particularly when G is the additive group of real numbers) and, for this s...

The Neighbor-Joining algorithm is a recursive procedure for reconstructing trees that is based on a transformation of pairwise distances between leaves. We present a generalization of the neighborjoining transformation, which uses estimates of phylogenetic diversity rather than pairwise distances in the tree. This leads to an improved neighbor-joining algorithm whose total running time is still...

Evidence from grassland experiments suggests that a plant community's phylogenetic diversity (PD) is a strong predictor of ecosystem processes, even stronger than species richness per se This has, however, never been extended to species-rich forests and host-parasitoid interactions. We used cavity-nesting Hymenoptera and their parasitoids collected in a subtropical forest as a model system to t...

BACKGROUND: Gammacoronaviruses, which are single-stranded, positive-sense RNA viruses, are responsible for a wide variety of existing and emerging diseases in birds. The Gammacoronaviruses primarily infect avian hosts. OBJECTIVES: This study aimed to investigate the genetic diversity of Gammacoronaviruses in quail population in Iran. METHODS: In the period from 2016 to 2018, samples from 47 qua...

Eukaryotic transcription is a highly regulated process involving interactions between large numbers of proteins. To analyse the phylogenetic distribution of the components of this process, six crown eukaryote group genomes were queried with a reference set of transcription-associated (TA) proteins. On average, one in 10 proteins encoded by these genomes were found to be homologous to sequences ...

We derive an invertible transform linking two widely used measures of species diversity: phylogenetic diversity and the expected proportions of segregating (non-constant) sites. We assume a bi-allelic (two-state), symmetric, finite site model of substitution. Like the Hadamard transform of Hendy and Penny, the transform can be expressed independently of the underlying phylogeny. Our results bri...

The vast majority of lichenicolous fungi are relatively host-specific, nonvirulent ascomycetes and heterobasidiomycetes. A few known lichenicolous homobasidiomycetes (mushroom-forming fungi) generally exhibit broad host ecologies and in some cases, high virulence. Many produce conspicuous sclerotia or bulbils, thought to be adaptive in dispersal and survival. To more clearly understand the evol...