Over at Evolutionary Genealogy, Leonard Eisenberg has been thinking about how we're related to other animals. Not so much in the evolutionary sense, but in the familial sense. After all, if your cousin is simply the offspring of your parent's sibling, why not continue that logic back a few hundred millennia or so?
"The important point is that since the origin of life belongs in the category of at least once phenomena, time is on its side. However improbable we regard this event, or any of the steps which it involves, given enough time it will almost certainly happen at-least-once. And for life as we know it, with its capacity for growth and reproduction, once may be enough." -George Wald