When a Pokémon evolves, a lot of its attributes change, such as types, base stats etc. Some, however, like egg cycles and leveling groups, stay the same.
Are there any other attributes or values that stay the same?
As an example, a Bulbasaur levels up medium slow, and needs 1059860 EP to reach level 100. These variables remain the same even when it evolves into an Ivysaur or Venusaur: they all level up medium slow.
They all also need 20 so called egg-cycles to hatch. If you hacked an egg that contained an Ivysaur, it would take just as long to hatch as a Bulbasaur would.
These values are constant and don't change during evolution, they are unique to each evolutionary family.
Those two, however, are the only attributes I can think of right now, and I just want to know if there are any other variables that remain the same among each evolutionary family.