An impressively well-preserved fossil turned out to be the ancient twin of Ghostbusters villain.
Fossils of a 508 million-year-old shrimp-like creature known as "Waptia" were discovered in China carrying several eggs with embryos. This find represents the earliest known evidence of brood care, researchers say.
Pre-reptile Bunostegos akokanensis is the earliest known creature to stand upright on all four legs. This species was thought to be a sprawler, but researchers from Brown University found that it had shoulders extending directly underneath its body instead of out to the sides.