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Image Gallery: Bizarre Cambrian Creature

Small sea life

cambrian fossil

(Image credit: Andrew Smith, Proc. Royal Soc. B)

In 2012, researchers unearthed a 520-million year old fossilized creature that is one of the earliest known echinoderms with fivefold symmetry.

Ancient find

Anti-Atlas mountain region in Morocco

(Image credit: Andrew Smith)

The animals skeleton had long since disintegrated, but it left a characteristic impression in the sediments of the Moroccan Anti-Atlas Mountains.

Primitive creature

cambrial fossil

(Image credit: Andrew Smith)

The creature, dubbed Helicocystis moroccoensis, had five spiral grooves along its body that it opened and closed to capture food.

Strange symmetry

A cambrian fossil echinoderm

(Image credit: Andrew Smith)

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

a Cambrian fossil called helicocystis moroccoensis

(Image credit: Andrew Smith)

The new creature may help shed light on when and how echinoderms evolved their unique body plans.

Explosion of life


(Image credit: Esben Horn)

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.

Ancient insects


(Image credit: Yie Jang (Yunnan University))

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.