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Assuming that evolutionary theory is a universal constant and species on other planets evolve to fulfil the demands of a habitat niche, it's still fairly unlikely that a lifeform would evolve to adopt the basically unnatural goal of space travel. You'd not only need to evolve niche-filling lifeforms, but also require the time for some of those lifeforms to adapt to multiple new roles instead of dying out. You'd then need time for one of those to understand its ability to modify its environment, and then grasp physics to a level where leaving their own planet even became an option. All that before their planet becomes uninhabitably close to it's star, the star explodes, the planet gets twatted by an asteroid etc. It's almost entirely improbable there is another intelligent life in our galaxy. If there's one in another galaxy and it reaches us then it's so advanced of us that we'll be wiped out in seconds.
