One model of the Northern Lowlands of Mars is that they were ancient sea beds. Were this the case, what sort of sea creatures might have lived in such a sea? Consider Yogi, the large rock next the Mars Pathfinder. If found on earth, the structures noted in the image above would be recognized as possibly being forms of sea life. More specifically brain coral. We won't know for sure until we get there and can put Yogi to the same scientific tests that we put Earth rocks to. For a volcanic explanation of the Northern Lowlands of Mars see http://www.timecrystal.com/Mars/Cydonia/