Linked from
The 17 pages that link to Endosymbiosis, each with the reason it gives.
SymbiosisBroader topic: It identifies the especially intimate arrangement of internal partners.
OrganelleNarrower topic: The proposed organelle ancestors began as intracellular symbionts.
ZooxanthellaeRelated: Zooxanthellae inhabit host cells rather than merely living nearby.
RiftiaBroader topic: Riftia houses its bacterial partners within specialized internal tissue.