The puzzle of human evolutionary history is littered with missing pieces. But new research is giving scientists a much clearer picture of where we came from. 

As outlined this week in six papers published in the journal Science, an international team of researchers have assembled the most complete skeleton to date of a half-ape, half-human ancestor named Australopithecus sediba, revealing "from head to heel," says Robert Lee Hotz at the Wall Street Journal, "a collage of primitive and modern anatomy." Living 2 million to 3 million years ago during what experts consider "the crucible of human evolution," Au. sediba stood about chest-high to modern humans, and possessed long, ape-like arms with nimble hands that closely resembled a human's. He also had an elongated, curved spine that contained the same number of vertebrae as ours.

The creature was indigenous to what's now South Africa, and trace microscopic plant elements found in its teeth suggest that Au. sediba was omnivorous — "largely a vegetarian" that possessed "a rather human-like chewing apparatus," says Peter Schmid of the University of Zurich, who spent time analyzing the remains.

How did it get around? Au. sediba spent most of its time swinging from tree to tree, and also possessed a small heel that resembled those of modern chimps. That means "it walked rather awkwardly," says Discovery News:

…with an inward rotation of the knee and hip, with its feet slightly twisted. The scientists conclude that this pigeon-toed way of walking on two limbs might have been an evolutionary compromise between walking upright and tree climbing. [Discovery News]

In other words, the half-ape, half-human ancestor plugging an invaluable void in humankind's evolutionary past? Probably a total dork. I mean, just look at him.