A cladogram is a diagram used in phylogenetics to represent the evolutionary relationships between different species or groups of organisms. Its primary purpose is to illustrate the branching pattern of evolutionary lineages, showing how taxa (species, genera, etc.) are related through common ancestors.
Structure of a Cladogram:
1. Branches (Clades): Each branch represents a clade, a group of organisms that includes an ancestor and all its descendants. Clades are monophyletic, meaning they contain all descendants of a common ancestor.
2. Nodes: Points where branches split, representing points of divergence or common ancestry.
3. Tips: The endpoints of branches, representing individual taxa (species or groups).
4. Root: The starting point of the cladogram, often representing the inferred common ancestor of all taxa included.
Cladograms are based on shared derived characteristics (synapomorphies) and are constructed using methods like maximum parsimony, maximum likelihood, or Bayesian inference. They are essential tools in understanding evolutionary history and taxonomic classification.
