Ancient Romans Had Crabs, But They Never Knew It

In 1997, a couple of zoologists were visiting the remains of Trajan's Forum in middle of Rome. They turned over a rock, and there, looking up at them, was an unassuming freshwater crab. They soon realized they had discovered a new species, Potamon fluviatile, the only freshwater crab species known to inhabit a large city:

http://www.physorg.com/news100094217.html

"So what?" you ask. Stupid crabs. All googly-eyed and leg-y. They'll pinch ya. Throw that puppy in a pot, boil it alive, and serve it up with some melted butter!

But the researchers didn't eat the crabs. They studied them, genetically. What they discovered is not just that Rome had crabs, but that those crabs had been there a very, very long time. So long, in fact, they pre-dated the forum, which was built in 112 AD, and even predated Rome itself (founded in 753 BC), all the way back about 3,000 years ago, to the time of the ancient Etruscans. The little buggers had been living in ancient Etruscan canals that ran under the forum and joined up with the ancient Roman sewage system.

What's more, the crabs are genetically unrelated to other Italian crabs. In fact, they are most closely related to Greek freshwater crabs, probably introduced all those millennia ago by Greek traders or colonists (BEFORE the time of Alexander the Great, Aristotle, Plato, or Socrates). Except that, without natural predators, the Roman crabs (which are about 12 cm, or 4.8 inches, wide) had evolved to be over twice the size of their Greek counterparts (which were only 5 cm, or about 2 inches, wide). There are now an estimated 1000 crabs down there.

So as the Etruscan culture fell and was replaced by the land of Romulus and Remus (no, I'm not talking about Star Trek Romulons, you geek!), through the rise of the Roman Republic, the rule of the Roman Empire, the fall of Rome to Germanic Barbarians, the rule of the Byzantines, the rise and fall of the Papal States, the Kingdom of Italy, through Italian Fascism and Mussolini, World War II, and the post-war reconstruction, no one knew that the crabs were down there, clicking away in the dark, feeding on algae and snails, as well as scraps of food and detritus that washed down from the city above. Yum!

I imagine that, occasionally, one of the little hard-shelled critters skittered up to the surface to take a look around and see what century it was, then retreated back down to crab paradise to report on the latest stupid human tricks:

Crab #1: "Hey, you wouldn't believe what those humans are up to these days. Some dude named Julius just got stabbed to death by a mob of his own homies."

Crab #2: "Cool. Did you bring back any scraps? I'm hungry."

Maybe, over those thousands of years, some Roman once in a while turned over a rock and found one of these little crustaceans staring up at them. The Roman probably thought, "Hey, free crab! Hail Caesar!" and boiled it alive for dinner. Mmmmm, with melted butter.....