Question: I was rewatching Stargate-SG1 and noticed something while I was watching "[Menace](http://stargate.wikia.com/wiki/Menace)" where we learn that the android Reese created the Replicators and sent them out in to the galaxy.

We know that the Replicators integrate technology they consume to their own and lastly we know of no race that were capable of travelling between galaxies (and that lives in the Milky Way) aside from the ancients

My question is, how did they end up in the [Asgard galaxy](http://stargate.wikia.com/wiki/Ida) (Ida) and why didn't they consume everything in the Milky Way long before the series began?

Is is ever explained?

![enter image description here](https://i.stack.imgur.com/jJP0K.jpg)

Answer: 
reese's planet was an ancient outpost for a small civilisation living in Ida, thus explaining the lack of other ancient tech. The people tried to evacuate home to The Ida Galaxy, but the replicators followed them and killed them anyway consuming all the ancient tech they could, the ancients tried to destroy what they can and so all the replicators went through in order to get as much as they could. This gives them a head start on the Asgard making it harder for them to contain/beat them. The ancients destroy the stargaze to late, allowing all the bugs through but essentially trapping them in Ida. Fan explanation, but not contradicted anywhere to my knowledge.
Expanding on one of Richard's comment above, an alternate, and bleak, explanation surfaces:

After lotusing Reese's planet, the replicators set out to search for food elsewhere.

At this point they encounter the Ancients, and integrate their technology and philosophy (to some extent) into their own.

Recognizing that Ancients pose a threat to their immediate dominance, they do the machiney thing and use their new-found hyper drives to colonize every galaxy the Ancients know of but are not present in, explaining their presence in Ida, and their absence in Pegasus and the Ori Home Galaxy.

In other words:

**The entire universe is overrun by replicators, except the Milky Way, Pegasus and Ori Home galaxies.**