This rat with way too many sharp teeth is your great x 4 x 10^6-grandmother. That's what scientists have discovered after six years of research—the Protungulatum donnae is the common ancestor to all mammals, from humans to horses to lions. All except Nicholas Cage, who descends from velociraptors.
The team, lead by Maureen A. O'Leary of Stony Brook University on Long Island, has found genetical and anatomical evidence that demonstrates that Protungulatum donnae is the "most likely" ancestor to every mammal. 66 million years ago—200,000 to 400,000 years after the end of the Cretaceous period—our common ancestor rose from the ashes of the extinct dinosaurs and took over the planet.
Literally. According to their research, every other mammal who lived at the time of the great dinosaurs died with them—about 39 mammalian lineages. Only the Protungulatum donnae, the Placentalia lineage, survived the catastrophe along with some reptiles. This furry thing is where we all started.
The insect-eating critter reproduced just like us, having a two-horned uterus and a placenta, which held the baby until it was fully formed for a live birth. Like humans, pumas or chimps, the mothers provided with nourishment to their babies while they were forming.
Talking to John Noble Wilford from the New York Times, Dr. O'Leary said that the discovery process "has stretched our own expertise. The findings were not a total surprise, but it's an important discovery because it relies on lots of information from fossils and also molecular data."
They were capable of arriving to this conclusion using MorphoBank, the largest database of data and images of mammals, both alive and extinct. Its relational power is enabling scientists to make discoveries like this. It's so powerful that everyone is jumping in. According to Dr. O'Leary a least a thousand scientists, "some from other countries, are already signing up to use MorphoBank."
So the next time some creationist says that we don't come from monkeys, you can agree with and say that, indeed, we don't come from monkeys, but his or her great-great-great-great-(...)-great-great-great-great-grandmother was this rat. [Science via New York Times]