Trilobites. At one time, they must have practically covered the earth, because now there are still

[raccoon]

tons of fossils of trilobites. And if there are that many that were fossilized, imagine how many there must have been in real life.
Any book about paleontology you pick up, I guarantee they’ll mention trilobites, and most probably have a picture of one.

Anybody here ever find a fossil of one?

[Warpy]

1. Partial fossil, yes. It was in a decorative rock

in somebody else's landscaping.

The one critter that always fascinated me was the horseshoe crab, sort of a living fossil. How did they know what day of the year to mass on the beaches? Because they did.

[Scuba]

2. Multiple partials in Wisconsin and one partial in an Arizona golf course sand trap.

[longship]

3. They lived on the bottom.

Fossils are common in sedimentary layers like sea bottoms. So trilobites are kind of preselected to be fossilized.

But yes, they were probably also common in the Cambrian.

(I am not an expert, and I don't even play one on TV. But that's my arguably limited understanding of this.)

[Viva_La_Revolution]

9. in the Cambrian, 85% of the earth was covered in water

warm shallow seas.. exactly right for Trilobites. Their shells were shed as they grew so most of what we find are discards. and yep, the sea floor was the perfect environment for preservation.

[StrayKat]

4. No, but the always look like giant pill bugs to me. n/t

[Scootaloo]

5. Found one in a chunk of sandstone when I was a kid

Being a kid, I tried to chip it loose... oops. The rock turned out to have all sorts of fossils in it, though that was the only trilobite I'd found.

And yup, there were a lot of them. They are well-preserved because they were bottom-dwellers with apparently thick shells, and they died out early enough that a lot of their beds had time to rise above sea level. They probably weren't any more numerous at any given moment than their modern ecological counterparts, crabs and isopods (probably less, given more of the world was deep ocean rather than fertile coastal / shelf areas) - but that's still a goddamn lot of trilobites.

Imagine if every cockroach on the planet had a one in a thousand chance of being fossilized; any future paleontologist would call the Permian-Homogenocene to be "Age of the Blattaria."

[Callmecrazy]

6. I found one...

Broke open a flat rock on the shore of Lake Erie.

[unblock]

7. they're all over the place in texas. they're chock-a-block in the limestone they use in construction

[lastlib]

8. hundreds of 'em.....

...one of my favorite camping grounds has 'em all over the place. It was part of an ancient seabed millions of years ago, and there are limestone cliffs and formations all around it. Crinoid fossils are also very common.

[exboyfil]

10. It is amazing that the flood

wiped out every last one 4,000 years ago. (sarcasm alert)

Now to put on my evolutionary hat. I think when a species comes up with a better mousetrap it experiences wild growth in its population. The armored trilobite did just that. Eventually critters evolved to eat that trilobite, and they are very interesting to behold (the Anomalocaris). Trilobites have been found with bites from it.

I have a fun book from DK called Prehistoric Life.

[Victor_c3]

11. I've never actually found one

but I'd love to go to a place where you could.

My 4 year old daughter is totally crazy about fossils and dinosaurs right now. For Christmas I bought her a box set of 20 different fossils and she is constantly looking at them. Sadly, the only really common fossil it doesn't have in it is a trilobite. I haven't gotten around to picking one up for her yet, but I've been on the lookout.

The fossils are great. You can't really break them as they are essentially rocks and I think it is very cool for a kid to be able to touch something that is hundreds of millions of years old.

I think her favorite fossil is a dinosaur caprolite (poop) fossil that we found at a local museum gift shop.

I thought girls were only supposed to like princesses and baby dolls?! I must be doing something wrong as both of my daughters love trucks, snakes, dinosaurs, science, and all that other "boy" stuff. I better be careful, I might end up with two girls who want to be scientist like their dad (I'm a chemist) when they grow up!