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Language Lineage

Before the trees

How we know

Four short explainers on the methods behind every tree on this site: how relationships are proved, what a sound law is, where the dates come from, and why some groupings are still argued over.

  1. 01The comparative methodHow linguists prove that languages are related, and how they reconstruct a language nobody wrote down.Read
  2. 02What a sound law isWhy sound change is regular, how the exceptions are explained, and how to read the notation on this site.Read
  3. 03How splits are datedWhere the dates on the trees come from, and why most of them are ranges.Read
  4. 04Why some groupings stay disputedWhat it takes to prove a relationship, why deep proposals rarely get there, and how this site labels them.Read