why can build something not yet researched

[gwgardner]

See screenshot, where in my current game I have not researched 'atmospheric dome' but I can build it. Any idea why? Is it a bug?

[later] I see now that my race started the game with the ability to produce the domes. I think that the tech tree should then show that it's already researched.

[zakblood]

the race you have chosen has it already, so not needed, once you try later on to add it, it will say already got and researched later on