There is, PSX. All stat bonuses, new buildings, new ships, new ship componets and new starbase modules are listed under each discovery in the tech tree.
IMO the tech tree is way too simple. Never do different tech lines converge, only a little more than half the discoveries give you a benefit, and when they do it's generally exactly the same as the last discovery in the line but taking up one less space or giving you a couple more research/manufacturing/morale points. Sure it limits the ability of a tech race to completely outclass a production race like MOO2 had problems with mid-game, but it feels a little limiting to know that spending those points in research does little except net you a couple more space points on a ship after attaching weapons than a race that spent points in getting an economy that could support twice the amount of ships you have.