Master of Orion II: Battle at Antares/Colonies should specialize

You've probably worked out the general principle already, from the examples in Growing your population, Feeding your people and Money matters. This page tries to pull these ideas together and give plenty of examples of what types of colonies should specialize in what.

The benefits of specialization are:
 * You maximize industrial, research and food output by doing them in the most suitable colonies.
 * You minimize building maintenance costs by not constructing buildings that do things for which colonies are not suitable.

Ship-building
In the earliest part of a game you have no option - only your homeworld has enough population to build ships. But as the game goes on, you should aim to do most of your ship-building at Medium or larger planets that are Rich or Ultra-rich and have large populations. If you don't have any of these:
 * Terraform sub-Terran Medium or larger planets that are Rich or Ultra-rich to increase their population capacity.
 * Meanwhile build ships at Large or Huge planets whose mineral rating is Abundant (i.e. average).

Medium or larger planets that are Rich or Ultra-rich and have large populations may be as good at farming or research as e.g. your homeworld, but the advantages of concentrating ship-building at the industrial monsters are:
 * You get faster ship production that way, while other planets can do research and / or farming just as well.
 * You probably reduce building maintenance costs by constructing the top-end construction and pollution-control buildings only at your ship-yard planets.

Food production
At your most fertile planets, of course, especially those with Natives:
 * Your empire will need fewer farmers to produce the same total food, so you'll have more people avaialbe for indstry and reseach.
 * You may reduce building maintenance costs by constructing the top-end farming-related buildings only at your fertile planets.

Farming is a less clear-cut case than ship-building:
 * You need to keep an eye on the costs of Freighter operations.
 * Sometimes you may run short of Freighters, e.g. if you'just conquered a no-food planet with a huge population.
 * You'll terraform some planets to increase their population capacity, an dtha t will often make them more fertile.

Research
Artifacts planets are best, even if they have relatively small populations:
 * Those with high populations should go all out for research, includig all the research buldings and morale boosters.
 * Low-population Artifacts planets still give a bonus of 2 RP per scienetist, while is almost as much as Supercomputer but without the maintenance cost.
 * If an Artifacts planet can easily be terraformed to give a large increase in population capacity, do it and then build the research and morale buildings.