Gene-tree/species-tree reconciliation compares gene trees with species trees to reconstruct evolutionary events such as gene duplication and gene loss. Learn the principles, workflow, applications, limitations, and role of reconciliation in comparative genomics and phylogenetics.
Gene family expansion and contraction describe changes in the number of related genes across evolutionary lineages. Learn how gene duplication, gene loss, functional diversification, phylogenetics, synteny, and comparative genomics help explain gene family evolution.
Gene family clustering groups related genes or proteins using sequence similarity, graph-based methods, hierarchical clustering, orthology, and phylogenetics. Learn the major approaches and their applications in comparative genomics.
Phylogenetic analysis of homologous genes helps reconstruct evolutionary relationships among genes and gene families. Learn about sequence selection, multiple sequence alignment, phylogenetic methods, evolutionary models, branch support, gene trees, and major applications in comparative genomics.
Learn how gene families are identified using sequence similarity, protein domains, motifs, clustering, orthology, multiple sequence alignment, phylogenetics, and genomic context.
Orthogroups are groups of genes descended from a common ancestral gene across a selected set of species. Learn how orthogroups relate to gene families, orthologs, paralogs, sequence similarity, phylogenetics, and comparative genomics.
Gene trees and species trees describe different aspects of evolutionary history. Learn how they are constructed, why they can differ, and how duplication, gene loss, incomplete lineage sorting, horizontal gene transfer, and other processes influence evolutionary relationships.
Synteny analysis compares the organization of genes across genomes. Learn how conserved gene order, genomic neighborhoods, and syntenic blocks help study orthologs, gene duplication, gene loss, and genome evolution.
A gene pool is the complete collection of genes and alleles within a reproducing population. This article explains how gene pools influence genetic diversity, evolution, and a population’s ability to adapt.
Sampling error is the random difference between a sample and the true population it represents. This article explains why sampling error occurs, how it affects biological studies, and its role in evolutionary processes.
An evolutionary trajectory describes the long‑term path a population follows as its genetic composition changes over generations. This article explains how selection, drift, mutation, and environmental pressures shape these trajectories.
A population bottleneck is a sharp reduction in population size that drastically reduces genetic diversity. This article explains how bottlenecks occur, how they drive genetic drift, and why their effects persist for generations.
Genetic drift is the random change in allele frequencies caused by chance events. This article explains how drift works, why it is strongest in small populations, and how bottlenecks and founder effects shape evolution.
