This game uses EOL TraitBank prenatal development and gestation-duration rows matched to the reviewed animal image manifest.

• For birds and some egg-layers, the value can be incubation or prenatal development duration.
• For mammals, it is usually gestation duration.
• The reveal source context keeps the exact EOL predicate, trait id, source URL, citation, and measurement units.

Different animals start the clock in different biological ways; the source row tells you which lane you are seeing.