SCIENCE LAB SPECIAL : EARLY JAWS

 

In a shell like a taco, surprising ingredients. About 70 percent of the animals on Earth are arthropods with mandibles, or pincerlike jaws.

To understand how organisms with this anatomical feature became so diverse and successful over the past 500 million years, scientists look inside the tack-like shell that protected an enigmatic creature that once swam prehistoric seas.

That creature, the arthropod Odaraia alata, roamed the seas of the middle Cambrian Period about 500 million years ago.

Odaraia was nearly eight inches long, and its hard covering most likely helped propel it through water, at times upside down.

An analysis of fossils presents evidence that Odaraia had mandibles and collected food in the open ocean, not only near the seafloor.

The study fills critical gaps in the evolutionary record of arthropods and the establishment of marine food webs.

The study also showed that Odarais's '' very bizarre '' legs were covered in many large spines and smaller spikes.

The World Students Society thanks Rebecca Dzombak.