Small sea life
In 2012, researchers unearthed a 520-million year old fossilized creature that is one of the earliest known echinoderms with fivefold symmetry.
The animals skeleton had long since disintegrated, but it left a characteristic impression in the sediments of the Moroccan Anti-Atlas Mountains.
The creature, dubbed Helicocystis moroccoensis, had five spiral grooves along its body that it opened and closed to capture food.
Earlier fossils had spiral arrangement of those grooves, or ambulacra, but not the distinctive five point symmetry found in sea urchins, starfish, and other echinoderms.
One of many
The new creature may help shed light on when and how echinoderms evolved their unique body plans.
Explosion of life
Helicocystis moroccoensis is just one of many primitive creatures that emerged during the Cambrian explosion, a period when the number of species on the planet exploded. Bizarre shrimplike sea monsters known as anomalocaridids grew up to 6 feet long and filled the Cambrian seas.
Another strange creature, a 500-million year old sea creature known as a fuxhianhuiid, had limbs under its head. Throughout the Cambrian period, life experimented with many wacky body plans.