Fangs for the memories! 518-million-year-old fossil helps explain spider's bite

Scientists say that a tiny well preserved fossil could help explain how spiders got their fangs.

The fossil belongs to an ancient sea creature - called Urokodia - which lived around 518 million years ago.

Researchers used special technology to look inside the fossil, and found small pincer-like parts located just behind its eyes.

Experts say the discovery could help them better understand how life was evolving on Earth at that time.

The study was led by an international team of scientists from the University of Leicester and Yunnan University in China.

They took a closer look at the fossil, found at the famous Chengjiang fossil site in southern China, where many other ancient animals have previously been discovered.

Experts say that Urokodia was a small sea animal, measuring around two to three centimetres long, with large eyes on stalks, a long segmented body and jointed limbs.

Researchers say that at first glance, it didn't look much like any modern-day spiders or scorpions.

However, when the team used special x-ray technology to look inside the fossil, they found two tiny pincer-like limbs just behind its eyes.

Scientists think these are the earliest known version of chelicerae - special fang or claw-like mouthparts that animals such as spiders, scorpions and ticks all have.

Scientists also found evidence that Urokodia may have breathed using gill-like structures, suggesting that it lived in the sea.

Co-author Professor Mark Williams, from the University of Leicester, explained: "Urokodia was part of an ancient ecosystem of over 200 different types of animals living in the seas over 500 million years ago.

These spectacularly preserved fossils provide real insights into how life was evolving on our planet at the very dawn of animals."