Related Experiment Video
Updated: Jun 23, 2026
08:57
Using Phylogenetic Analysis to Investigate Eukaryotic Gene Origin
Published on: August 14, 2018
Recovering evolutionary trees under a more realistic model of sequence evolution
P J Lockhart1, M A Steel, M D Hendy
1School of Biological Sciences, Massey University, New Zealand.
Molecular Biology and Evolution
|April 28, 2009
Summary
A new LogDet transformation corrects phylogenetic tree reconstruction errors caused by differing DNA compositions. This method improves accuracy for evolutionary analyses, especially with asymmetric models.
Area of Science:
- Evolutionary biology
- Bioinformatics
- Phylogenetics
Background:
- Existing phylogenetic methods often group sequences by nucleotide composition, not evolutionary history.
- Differing nucleotide frequencies can mislead tree reconstruction, even with high statistical support.
Purpose of the Study:
- Introduce the LogDet transformation for accurate phylogenetic analysis.
- Address limitations of current methods in handling varied nucleotide compositions.
Main Methods:
- Developed the LogDet transformation using determinants of divergence matrices.
- Applied the transformation to theoretical and biological datasets (chloroplasts, nuclear, mitochondrial DNA).
Main Results:
- LogDet transformation provides accurate phylogenetic inference for sequences with diverse nucleotide compositions.
- Demonstrated LogDet's effectiveness on datasets where traditional methods failed.
- Highlighted the impact of irregular base compositions on tree reconstruction.
Conclusions:
- LogDet transformation offers a robust solution for phylogenetic inference.
- Irregular nucleotide compositions are a significant factor that can bias evolutionary studies.
- Many published phylogenetic studies may require reevaluation due to potential biases.
Related Concept Videos
02:54Evolutionary Relationships through Genome Comparisons
Genome comparison is one of the excellent ways to interpret the evolutionary relationships between organisms. The basic principle of genome comparison is that if two species share a common feature, it is likely encoded by the DNA sequence conserved between both species. The advent of genome sequencing technologies in the late 20th century enabled scientists to understand the concept of conservation of domains between species and helped them to deduce evolutionary relationships across diverse...
03:21Phylogenetic Trees
Phylogenetic trees come in many forms. It matters in which sequence the organisms are arranged from the bottom to the top of the tree, but the branches can rotate at their nodes without altering the information. The lines connecting individual nodes can be straight, angled, or even curved.The length of the branches can depict time or the relative amount of change among organisms. For instance, the branch length might indicate the number of amino acid changes in the sequence that underlies the...
03:21Phylogenetic Trees
Phylogenetic trees come in many forms. It matters in which sequence the organisms are arranged from the bottom to the top of the tree, but the branches can rotate at their nodes without altering the information. The lines connecting individual nodes can be straight, angled, or even curved.The length of the branches can depict time or the relative amount of change among organisms. For instance, the branch length might indicate the number of amino acid changes in the sequence that underlies the...
01:28Microbial Phylogeny
Understanding the evolutionary relationships among microorganisms is fundamental to microbial ecology and taxonomy. Phylogenetic trees are essential tools for inferring these relationships, relying primarily on comparative analyses of molecular sequences such as DNA, RNA, or proteins. In microbial studies, these trees typically depict the evolutionary paths of diverse bacterial and archaeal species by mapping genetic differences accumulated over time.Phylogenetic trees are composed of tips,...
01:23Phylogeny
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire...
01:19Survival Tree
Survival trees are a non-parametric method used in survival analysis to model the relationship between a set of covariates and the time until an event of interest occurs, often referred to as the "time-to-event" or "survival time." This method is particularly useful when dealing with censored data, where the event has not occurred for some individuals by the end of the study period, or when the exact time of the event is unknown.
Building a Survival Tree
Constructing a survival tree begins...
Building a Survival Tree
Constructing a survival tree begins...