BACKGROUND Molecular dating has gained ever-increasing interest since the molecular clock hypothesis was proposed in the 1960s. Molecular dating provides detailed temporal frameworks for divergence events in phylogenetic trees, allowing diverse evolutionary questions to be addressed. The key aspect of the molecular clock hypothesis, namely that differences in DNA or protein sequence between two...

> Abstract There is no consensus on the inter-ordinal relationships of eumalacostracans, despite the recent synthesis of several morphological matrices with data from four molecular markers. Signals from different molecules confl ict with each other, and all are conspicuously at odds with morphology. Can fossils help to resolve the problem? Here, we utilize palaeontological data in two ways. Fi...

Background and Aims: CBLVd has been reported from northern of Iran previously. The aim of this study was evaluating new viroid variant from asymptomatic citrus trees of Fars province and comparing with its other isolates. Materials and Methods: In this study a number of citrus trees without symptoms were sampled and subjected to RNA extraction followed by RT-PCR, cloning and sequencing of ...

Within the biological sciences, phylogenetics has long been relegated to a selected sector of scientists interested in the evolutionary history of organisms. Recently, it has become widely accepted that molecular sequence data is best analyzed in a phylogenetic context if predictive statements are to be made concerning lineagebased relationships among genes in large gene families, origins of ge...

Sponge classification has long been based mainly on morphocladistic analyses but is now being greatly challenged by more than 12 years of accumulated analyses of molecular data analyses. The current study used phylogenetic hypotheses based on sequence data from 18S rRNA, 28S rRNA, and the CO1 barcoding fragment, combined with morphology to justify the resurrection of the order Axinellida Lévi, ...

Drugs and other chemical compounds are often modeled as polygonal shapes, where each vertex represents an atom of the molecule, and covalent bonds between atoms are represented by edges between the corresponding vertices. This polygonal shape derived from a chemical compound is often called its molecular graph, and can be a path, a tree, or in general a graph. An indicator defined over this mol...

Divergence date estimates are central to understand evolutionary processes and depend, in the case of molecular phylogenies, on tests of molecular clocks. Here we propose two non-parametric tests of strict and relaxed molecular clocks built upon a framework that uses the empirical cumulative distribution (ECD) of branch lengths obtained from an ensemble of Bayesian trees and well known non-para...

Pear (Pyrus spp.) is one of the most important edible fruits belonging to family Rosaceae. DNA markers, molecular genetics and genomics, breeding pear have greatly progressed over last few decades. The development reliable such as simple sequence repeats single nucleotide polymorphisms, has allowed profiling accessions, assessment genetic diversity within species, analyses phylogenetic relation...

Ever since the discovery of a molecular clock, many methods have been developed to reconstruct the molecular evolutionary phylogenetic trees. In this paper, we deal with this problem from the viewpoint of an inductive inference and apply Rissanen’s minimum description length principle to extract the minimum complexsty phylogenetic tree. OUT method describes the complexity of molecular phylogene...