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Figure 1 | BMC Evolutionary Biology

Figure 1

From: Utility of characters evolving at diverse rates of evolution to resolve quartet trees with unequal branch lengths: analytical predictions of long-branch effects

Figure 1

An unrooted four-taxon tree in an ultrametric form, with an internode of length (in time) t 0 and four subtending branches of lengths (in time) T 1, T 2, T 3, and T 4. The ancestral states of a molecular character at the two ends of the internode are denoted as M and N. The character states at the terminal tips of the four subtending branches are denoted as C 1, C 2, C 3, and C 4. The average substitution rate of the character over the internode and the four subtending branches is denoted as λ 0, λ 1, λ 2, λ 3, and λ 4. The expected number of character state changes in the internode and the four subtending branches are thus given by λ 0 t 0, λ 1 T 1, λ 2 T 2, λ 3 T 3, and λ 4 T 4, respectively.

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BMC Ecology and Evolution

ISSN: 2730-7182

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