The Cambrian explosion produced a host of bizarre and complex lifeforms, like this filter-feeding sea monster, dubbed Tamiscolaris borealis, that was unearthed in Greenland.
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Fossils of Ctenophores
Credit: Ou et al. Sci. Adv. 2015;1:e1500092
Scientists had assumed that comb jellies that lived during the Cambrian period were likely just as much of blobs as today's ctenophores, or members of…Read More »
the phylum Ctenophora. But new evidence from the fossil-rich site Chengjiang, in southwestern China, suggests otherwise. Here the fossil imprints of some of the comb jellies, which lived about 520 million years ago and showed the telltale cilia or hairlike structures on their bodies. The imprints belong to: Thaumactena ensis (A to D), Galeactena hemispherica (E to I), and Batofasciculus ramificans (J to N). Less «
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Credit: Dr. Qiang Ou and his colleagues
The comb jellies, which are not true jellyfish and did not have stinging cells nor did they sport tentacles, were protected with hard, spiny skeletons.…Read More »
The little creatures may have resembled Christmas ornaments, as shown in this illustration. The research, which you can read more about in the full news article, was detailed on July 10, 2015, in the journal Science Advances. Less «
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Credit: Jie Yang | Yunnan University
A "super-armored" worm fossil discovered in what is now southern China was rather leggy. Called Collinsium ciliosum, or Hairy Collins' Monster (after paleontologist…Read More »
Desmond Collins who discovered a fossil in this family in Canada in the 1980s), the creature would've sported 30 legs — 18 of which were tipped with claws to anchor the animal to penetrable surfaces and 12 feathery limbs would have waved back and forth in order to catch nutrients in the water.
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Credit: Javier Ortega-Hernández
Collinsium ciliosum was one the world's first armored animals, the researchers said. It used its spiky covering to protect itself from predators some 518…Read More »
Credit: “A superarmored lobopodian from the Cambrian of China and early disparity in the evolution of Onychophora,” by Jie Yang et al. PNAS 2015. 10.1073/pnas.1505596112.
Researchers found 29 fossils of Collinsium ciliosum, a wormlike animal with legs, in the early Cambrian Xiaoshiba biota of China.
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Credit: Elyssa Rider.
The fossil of a 505-million-year-old worm, now dubbed Hallucigenia sparsa, was discovered in the 1970s. At the time researchers thought its head was its…Read More »
tail and its legs were spines. Now in addition to righting its head and backside, scientists have found the bizarre creature is the ancestor of today's velvet worms, a group that includes sluglike animals with centipede-type legs. Less «
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Credit: Martin Smith, University of Cambridge / Smithsonian Institution.
The odd worm Hallucigenia sparsa gets its moniker from the word "hallucination," due to the animal's bizarre body — its head looks like its tail,…Read More »
it sports multiple leg pairs and strange back spines. The 1.3-inch-long (35 millimeters) worm lived on the seafloor during the Cambrian explosion. Less «
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Velvet worm claw
Credit: Martin Smith, University of Cambridge.
The ancient worm had a row of spines along its back and seven or eight pairs of clawed legs. It was these leg claws that revealed the worm's family relationships.…Read More »
Its claws are made up of a fingernail-like material that was stacked like cups; its structure matched that found in the modified chewing claws (shown here) of modern-day velvet worms. Less «
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Hallucigenia Worm Illustration
Credit: Danielle Dufault (Video Screengrab)
The Hallucigenia sparsa worm was uncovered in Canada's Burgess Shale, one of the world's richest fossil sites. The ancient creature, which lived during…Read More »
the Cambrian period some 508 million years ago, had a 0.6-inch-long (15 millimeters) wormy body covered in spines on top and 10 pairs of spindly legs down below. And because of the animal's odd body plan and specimens available, only recently were researchers able to decipher where its face was. Turns out, it has a doozy of a mouth: a circular opening lined with teeth. The inside of its mouth and throat were also lined with teeth pointed toward the gut. Less «
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Hallucigenia worm illustration
Credit: Danielle Dufault
The Hallucigenia sparsa worm had quite a grin — a circular mouth lined with needlelike teeth. More teeth lined the inside of its mouth and throat, researchers found.
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Hallucigenia worm fossil
Credit: Jean-Bernard Caron
The Hallucigenia sparsa worm was uncovered in Canada's Burgess Shale, one of the world's richest fossil sites.
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Credit: Yie Jang (Yunnan University)
The Cambrian period saw a rise in complex life forms like this early arthropod from simple multi-cellular creatures.
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Credit: Yie Jang (Yunnan University)
Because the ancient arthropods, fuxhianhuiid, were fossilized in a flipped position in a region of Southwest China, they are only example of preserved feeding limbs in this species.
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Credit: Yie Jang (Yunnan University)
A site in Southwest China has revealed a rich trove of creatures from the Cambrian period, including the only example of a nervous system that extends past the head.
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Rich fossil mine
Credit: Smithsonian Institution, Courtesy of Douglas Erwin
Arthropods from the Burgess shale, such as the trilobite Olenoides and a chelicerate called Sidneyia, exploded in morphological diversity following the so-called Cambrian Explosion.
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Credit: The Burgess Shale Geoscience Foundation - Field, BC - Canada
Trilobites are a common find at the Burgess Shale.
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Credit: Adrian Kin
A chain of trilobites preserved in Poland's Holy Cross Mountains.
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Credit: Marianne Collins (C)AAAS/Science-2007
Paleontologists have also identified a a slug-like creature covered with prickly armor at the Burgess Shale
The Cambrian also saw the rise of larger creatures, such as this 2-foot-long ancient shrimplike creatures called anomalocaridids, which had spiny head limbs for catching prey
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Cambrian sea monster
Credit: Esben Horn
The Cambrian also saw the rise of larger creatures, such as this 2-foot-long ancient shrimplike creatures called anomalocaridids had long, which had spiny head limbs for catching prey
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Credit: Andrew Smith
During the Cambrian explosion, the diversity of life exploded and bizarre sea creatures such as the Helcocystis moroccoensis flourished.
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Credit: Andrew Smith, Proc. Royal Soc. B
The strange animal had a set of five spiral grooves around its cigar-shaped body that it used to filter food from the water. This unique five point symmetry…Read More »
may shed light on when echinoderms such as starfish and sea urchins evolved their unique body plan symmetry. Less «
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Credit: Peiyun Cong
A spectacularly preserved creature, dubbed Lyrarapax unguispinus, was unearthed in China. The 520-million-year-old sea creature was so well-preserved that…Read More »
parts of its brain and nervous system were clearly defined. Less «
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Tia has interned at Science News, Wired.com, and the Milwaukee Journal Sentinel and has written for the Center for Investigative Reporting, Scientific American, and ScienceNow. She has a master's degree in bioengineering from the University of Washington and a graduate certificate in science writing from the University of California Santa Cruz.