Evidence of Flowing Water on Mars in Antarctica

I know my post title makes no sense. I am saying that there is evidence of flowing water on Mars because of something that exists in Antarctica. I know that makes it only slightly clearer what I am talking about. Perhaps the best thing to clear the confusion of what I am saying is to go read this article. Basically the article discusses how images of Mars have been compared to the feature of the McMurdo Dry Valleys to try and prove that there was once water on Mars.