Dendrogram

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title: "Dendrogram" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["trees-(data-structures)", "statistical-charts-and-diagrams", "graph-drawing", "cluster-analysis"] description: "Diagram with a treelike structure" topic_path: "technology/algorithms" source: "https://en.wikipedia.org/wiki/Dendrogram" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Diagram with a treelike structure ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/c/c5/UPGMA_Dendrogram_Hierarchical.svg" caption="chapter=Phylogenetic inference}})."] ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/8/83/Global-Diversity-of-Sponges-(Porifera)-pone.0035105.s008.tif" caption="doi-access = free }}"] ::

]] ::figure[src="https://upload.wikimedia.org/wikipedia/commons/7/70/Phylogenetic_tree.svg" caption="doi-access = free}} The vertical line at bottom represents the [[last universal common ancestor]] (LUCA)."] ::

::figure[src="https://upload.wikimedia.org/wikipedia/commons/1/16/Heatmap_RNAseqV2_1.png" caption="Heatmap of [[RNA-Seq]] data showing two dendrograms in the left and top margins."] ::

A dendrogram is a diagram representing a tree graph. This diagrammatic representation is frequently used in different contexts:

• in hierarchical clustering, it illustrates the arrangement of the clusters produced by the corresponding analyses.
• in computational biology, it shows the clustering of genes or samples, sometimes in the margins of heatmaps.
• in phylogenetics, it displays the evolutionary relationships among various biological taxa. In this case, the dendrogram is also called a phylogenetic tree.

The name dendrogram derives from the two ancient greek words (), meaning "tree", and (), meaning "drawing, mathematical figure".

Clustering example

For a clustering example, suppose that five taxa (a to e) have been clustered by UPGMA based on a matrix of genetic distances. The hierarchical clustering dendrogram would show a column of five nodes representing the initial data (here individual taxa), and the remaining nodes represent the clusters to which the data belong, with the arrows representing the distance (dissimilarity). The distance between merged clusters is monotone, increasing with the level of the merger: the height of each node in the plot is proportional to the value of the intergroup dissimilarity between its two daughters (the nodes on the right representing individual observations all plotted at zero height).

References

Citations

Sources

References

1. (1996). "Molecular Systematics, 2nd edition". Sinauer.
2. (1990). "Towards a natural system of organisms: proposal for the domains Archaea, Bacteria, and Eucarya". Proc Natl Acad Sci USA.
3. Everitt, Brian. (1998). "Dictionary of Statistics". Cambridge University Press.
4. (May 2009). "The History of the Cluster Heat Map". The American Statistician.
5. "Phylogenetic tree (biology)".
6. Bailly, Anatole. (1981-01-01). "Abrégé du dictionnaire grec français". Hachette.
7. Bailly, Anatole. "Greek-french dictionary online".

::callout[type=info title="Wikipedia Source"] This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page. ::