if you went back to the time when the earliest recognizable horseshoe crabs appeared—much different from today's horseshoe crabs, but definitely something you would look at and be like, "that's a tiny horseshoe crab"—there wouldn't be a whole lot else you would recognize! some bivalves, maybe. (shout-out to @dantheclammanDr. Dan Killam). our own ancestors would just be boring nondescript little worms. and i think that's beautiful