Fossilized arthropod has spider-like brain

Archaeologists just discovered the best example of a preserved nervous system ever.

The network of nerves belonged to a big-clawed aquatic arthropod that scientists believe was some early version of a scorpion or spider. The find confirms that the two modern animals once had related ancestors. (Via NBC)

The scientists found evidence of brain, eyes and a long, segmented trunk in the roughly inch-long specimen.

This organized evidence was thanks to iron deposits, which "had selectively accumulated in the animal's nervous system at the time of fossilization, and that let researchers image the nervous system hundreds of millions of years later." (Via The Los Angeles Times)

Scientists mapped out the neural network using a CT scanner. It was in such good shape that it could be directly compared to its living counterparts. Researcher Greg Edgecombe explains:

"By having access to the nervous system it allows us to study the evolutionary relationships of very ancient fossils using the same kind of information that we would use for living animals." (Via BBC)

And the researchers found evidence of head-mounted appendages the animals probably used for grasping things. Researcher Nick Strausfeld says they’re features that eventually became spider fangs.

"The parts of the brain that provide the wiring for where these large appendages arise are very large in this fossil. Based on their location, we can now say that the biting mouthparts in spiders and their relatives evolved from these appendages." (Via

The full results of the study have been published in the journal Nature.

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