The irirdiums do not start with the technology to colonize planets. This was mentioned in the streams as something they are tinkering with to balance out the races starting abilities.
The iridiums get awesome starting abilities but is handicaped by not able to colonize right off the bat and need to research the Colonizing techs to get the modules to build the ships.
Same for Drengin.
The Altarians and Earthers get colony ships. Altarians do not get constructors at first but Earthers do.
Hope this helps.
