Where did the sea scorpions go?

A recent discovery prompted me to discuss a group of now extinct animals known as the eurypterids or sea scorpions.



These aquatic invertebrates, though not truly scorpions, share similarities with scorpions, as well as spiders and horseshoe crabs. Geological evidence suggests they lived from approximately 460 to 252 million years ago (Ordovician-Permian).

Though some were a relatively small, yet respectable, eight inches long, others exceeded eight feet in length!


Jaekelopterus compared to a human.

Though fossils of these animals, which numbered at least 250 species, have been discovered on all continents except Antarctica, they no longer exist today. Notably, they disappear from the fossil record at the Permian-Triassic rock boundary, which corresponds to about 252 million years ago. This is thought to correspond with the largest mass extinction in earth’s history, with many different causes (e.g., volcanism, meteor impacts, runaway greenhouse effect) hypothesized to have contributed to this mass dying out of species. As I’ve discussed earlier, this is also where the reptilian captorhinids disappear from the fossil record.



Though I’m sure plenty of people are happy to know that underwater “scorpions” no longer roam the seas, they represent yet another example of a group of organisms that have disappeared from earth.

Questions for Creationists

Where did the eurypterids go? If fossils of them have been found on every continent except Antarctica, suggesting a widespread distribution, why don’t we see any today? If they lived in oceans and freshwater, shouldn’t they have survived Noah’s flood? Why do they suddenly disappear from the fossil record at the same point as captorhinids?

Photo credit

Source 1, Tony Martin, Simon Powell 


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s