Trilobites

Trilobites are creatures who were alive in the Cambrian period and then refused to fucking die until the end of the Permian period when nature gave a big "fuck you" to life and killed a lot of it in the Great Dying
They were little guys despite being called a "dominant species" of their time and it actually refers to how fucking many you could find because there were a lot of trilobites and they kept fucking because thats what creatures do
Also they are arphropods and related to spiders and scorpions which is cool but who decided that these little guys should be related to the nightmare fuel that is a Huntsman spider??
They also fossilized really well because they evolved exoskeletons and that made them preserve in sediment better than a soft-bodied creature would so therefore we have more evidence of how abundant they were.
They are called Trilobites because of their segmented body plan and the number 3 aka "tri"
Their main defense mechanism was to curl up into a ball because their outer shell was strong and would protect them and we know this because of an area with a lot of fossils where its presumed a mudslide or something similar happened, and trapped a bunch of creatures in sediment. And among those fossils were a bunch of trilobites curled into themselves because they did that in response to being buried, but then couldnt uncurl themselves to get out and suffocated as a result

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