Going nuclear: gene family evolution and vertebrate phylogeny reconciled

Gene duplications have been common throughout vertebrate evolution, introducing paralogy and so complicating phylogenctic inference from nuclear genes. Reconciled trees are one method capable of dealing with paralogy, using the relationship between a gene phylogeny and the phylogeny of the organisms containing those genes to identify gene duplication events. This allows us to infer phylogenies from gene families containing both orthologous and paralogous copies. Vertebrate phylogeny is well understood from morphological and palaeontological data, but studies using mitochondrial sequence data have failed to reproduce this classical view. Reconciled tree analysis of a database of 118 vertebrate gene families supports a largely classical vertebrate phylogeny

Community next steps for making globally unique identifiers work for biocollections data

Biodiversity data is being digitized and made available online at a rapidly increasing rate but current practices typically do not preserve linkages between these data, which impedes interoperation, provenance tracking, and assembly of larger datasets. For data associated with biocollections, the biodiversity community has long recognized that an essential part of establishing and preserving linkages is to apply globally unique identifiers at the point when data are generated in the field and to persist these identifiers downstream, but this is seldom implemented in practice. There has neither been coalescence towards one single identifier solution (as in some other domains), nor even a set of recommended best practices and standards to support multiple identifier schemes sharing consistent responses. In order to further progress towards a broader community consensus, a group of biocollections and informatics experts assembled in Stockholm in October 2014 to discuss community next steps to overcome current roadblocks. The workshop participants divided into four groups focusing on: identifier practice in current field biocollections; identifier application for legacy biocollections; identifiers as applied to biodiversity data records as they are published and made available in semantically marked-up publications; and cross-cutting identifier solutions that bridge across these domains. The main outcome was consensus on key issues, including recognition of differences between legacy and new biocollections processes, the need for identifier metadata profiles that can report information on identifier persistence missions, and the unambiguous indication of the type of object associated with the identifier. Current identifier characteristics are also summarized, and an overview of available schemes and practices is provided

Wikipedia as an encyclopaedia of life

In his 2003 essay E O Wilson outlined his vision for an “encyclopaedia of life” comprising “an electronic page for each species of organism on Earth”, each page containing “the scientific name of the species, a pictorial or genomic presentation of the primary type specimen on which its name is based, and a summary of its diagnostic traits.” Although the “quiet revolution” in biodiversity informatics has generated numerous online resources, including some directly inspired by Wilson's essay (e.g., "http://ispecies.org":http://ispecies.org, "http://www.eol.org":http://www.eol.org), we are still some way from the goal of having available online all relevant information about a species, such as its taxonomy, evolutionary history, genomics, morphology, ecology, and behaviour. While the biodiversity community has been developing a plethora of databases, some with overlapping goals and duplicated content, Wikipedia has been slowly growing to the point where it now has over 100,000 pages on biological taxa. My goal in this essay is to explore the idea that, largely independent of the efforts of biodiversity informatics and well-funded international efforts, Wikipedia ("http://en.wikipedia.org/wiki/Main_Page":http://en.wikipedia.org/wiki/Main_Page) has emerged as potentially the best platform for fulfilling E O Wilson’s vision

GA4GH: International policies and standards for data sharing across genomic research and healthcare.

The Global Alliance for Genomics and Health (GA4GH) aims to accelerate biomedical advances by enabling the responsible sharing of clinical and genomic data through both harmonized data aggregation and federated approaches. The decreasing cost of genomic sequencing (along with other genome-wide molecular assays) and increasing evidence of its clinical utility will soon drive the generation of sequence data from tens of millions of humans, with increasing levels of diversity. In this perspective, we present the GA4GH strategies for addressing the major challenges of this data revolution. We describe the GA4GH organization, which is fueled by the development efforts of eight Work Streams and informed by the needs of 24 Driver Projects and other key stakeholders. We present the GA4GH suite of secure, interoperable technical standards and policy frameworks and review the current status of standards, their relevance to key domains of research and clinical care, and future plans of GA4GH. Broad international participation in building, adopting, and deploying GA4GH standards and frameworks will catalyze an unprecedented effort in data sharing that will be critical to advancing genomic medicine and ensuring that all populations can access its benefits

Tree View: An application to display phylogenetic trees on personal computers

No abstract available

Introduction to inferring evolutionary relationships

This unit provides a general introduction to phylogeny. It defines common terms and discusses the issue of rooting trees, in addition to comparing gene and species trees. Methods for inferring phylogenies, such as distance methods, parsimony methods, and maximum likelihood are also presented. The unit concludes with discussion of how to assess tree confidence

Temporal congruence and cladistic analysis of biogeogrphy and cospeciation

Cladistic analysis of congruence between different area cladograms, and between parasite and host cladograms, is typically limited to comparing branching sequences only. Adding information on timing of the cladogenetic events can increase the power of the analysis. Instances where two cladograms have the same branching pattern but the relevant events occurred at different times can be distinguished from genuine congruence (cladistic and temporal agreement). Temporal information can also help resolve instances of apparent incongruence. As an example, I reanalyze data from Hafner and Nadler's (1988, Nature, 332:258–259; 1990, Syst. Zool., 39:192–204) elegant study of cospeciation between pocket gophers and their chewing lice. By combining both cladistic and temporal information, estimates can be made of relative roles of cospeciation, dispersal, and extinction in structuring the pattern of host-parasite association between the gophers and their lice

Wikidata and the bibliography of life

iological taxonomy rests on a long tail of publications spanning nearly three centuries. Not only is this literature vital to resolving disputes about taxonomy and nomenclature, for many species it represents a key source—indeed sometimes the only source—of information about that species. Unlike other disciplines such as biomedicine, the taxonomic community lacks a centralised, curated literature database (the “bibliography of life”). This article argues that Wikidata can be that database as it has flexible and sophisticated models of bibliographic information, and an active community of people and programs (“bots”) adding, editing, and curating that information

Maps Between Trees And Cladistic Analysis Of Historical Associations Among Genes, Organisms, And Areas

.The concept of a reconciled tree arose independently in molecular systematics, parasitology, and biogeography as a means of describing "historical associations." Examples of historical associations include genes and organisms, host and parasitic organisms, and organisms and areas. A reconciled tree combines the tree for a host and its associate into a single summary of the historical association between the two entities under the assumption that no horizontal transmission of associates has occurred. This paper defines reconciled trees, describes an algorithm for their computation, and develops measures to quantify the degree of fit between host and associate trees. Examples are given of applying the method to gene trees and species trees, host-parasite cospeciation, and biogeography. The problem of incorporating horizontal transmission of associates (e.g., dispersal or host switching) is also addressed by introducing the concept of maximizing the amount of codivergence (shared history..