Meet the oldest supershark, the newest Arctic dinosaur, the Carolina Butcher and more
From a spongelike speck to a bird built to terrify, 2015’s fossil finds added details, drama — and some real characters — to the story of life on Earth. These specimens flesh out life’s timeline too, spanning nearly 600 million years of history.
600 million years ago
Ancient sponge ancestor
Barely the size of a pinhead, this tiny creature (called Eocyathispongia qiania) had tubular chambers and surface cells that resemble those of modern sponges (SN: 4/4/15, p. 12).