Does an octopus have three hearts?

The Claim

Octopuses have three hearts.

The Answer

Museum and aquarium explainers describe two hearts that move blood through the gills and one that moves blood through the body.

Why This Is Surprising

It sounds like the kind of claim that races around social feeds without context. The source trail matters because the best version of the wonder is the verified one.

How We Checked It

We looked for an authoritative primary source, checked the wording against at least one credible secondary source when available, and recorded the last review date.