Phylogenetic covariance and comparative trait methods
Species traits can be correlated because related lineages share evolutionary history.
Key knowledge
Species traits can be correlated because related lineages share evolutionary history. Under an explicit Brownian trait model on a timed tree, shared branch history determines expected covariance; independent-contrast or likelihood methods account for that structure instead of treating every tip as an independent observation. Tree/model uncertainty and measurement error affect the resulting rate or association inference.
Conditions and scope
- Brownian evolution is a comparison model, not a universal claim that real traits change only neutrally.
- Contrasts require the appropriate variance scaling and branch treatment; correlation still does not establish causal adaptation.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Read standardized-contrast assumptions and covariance likelihood; excluded printed contrast division by variance instead of standard deviation, weighted-mean denominator typo, unrestricted raw-contrast-independence claim and compulsory log-transform rule.
2026-10-10 · Independent AI editorial review: All 115 actual compact claims, hypotheses, equation/variable/unit tables and 251 origin semantic links independently read. All exact author source-binding rows and disclosed extents assessed; targeted original bodies or specifically identified indexed primary passages rechecked below. All retained biology compact records read for combined breadth. Independent AI editorial content and practical common-core inventory review; no human specialist, degree/laboratory proficiency, whole-textbook certification or experimental replication. Receipt: biology-independent-content-inventory-review.1.
Entry details
Permanent link to this entry ↗- Record identity
- uni-bio-phylogenetic-comparisons
- Revision
- core.1
- Structured reference record
- University core expansion