Other races go to war too easily in Beta 2B

In the current beta, which I've been putting through its paces today, the computer-player races get too hostile too fast and go to war with me for no apparent reason. For instance, I make contact with the Altarian Republic, I have very little contact with them other than a technology swap, and then, out of the blue, as far as I can determine, they declare war on me. This doesn't make much sense to me even if one assumes that all the other spacefaring powers are alarmed by the emergence of the new kid on the block.