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The Mutant All-Female Crayfish, Which Reproduces by Cloning Itself, Is Filling Europe at Alarming Speed (atlasobscura.com)
The marbled crayfish looks much like any other freshwater crustacean. It has two claws, ten legs, and an attractive blue-brown marbled shell. Yet this six-inch creature, found in streams and lakes around the world, is far more sinister than you might expect. From a report: Its new scientific name gives a few clues: Procambarus virginalis. Every marbled crayfish, known as a marmorkreb in German, is female -- and they reproduce by cloning themselves. Frank Lyko, a biologist at the German Cancer Research Center, first heard about the marbled crayfish from a hobbyist aquarium owner, who picked up some "Texas crayfish" at a pet shop in 1995. They were strikingly large, and they laid enormous batches of eggs -- hundreds, in a single go. Soon, the New York Times reports, the hobbyist was beset with so many crayfish he was giving them away to his friends. And soon after that, marmorkrebs were showing up in pet stores upon Europe.
There was something very strange about these crayfish. They were all female, and they all laid hundreds of eggs without mating. These eggs, in turn, hatched into hundreds more females -- with each one growing up fully able to reproduce by herself. In 2003, scientists sequenced their DNA and confirmed what many owners already believed to be the case: Each baby crayfish was a clone of its mother, and they were filling Europe's fishtanks at alarming speed. Just 25 years ago, the marbled crayfish did not exist at all. Now, they can be found in the wild by the millions in Germany, the Czech Republic, Hungary, Croatia, the Ukraine, Japan, and Madagascar.
There was something very strange about these crayfish. They were all female, and they all laid hundreds of eggs without mating. These eggs, in turn, hatched into hundreds more females -- with each one growing up fully able to reproduce by herself. In 2003, scientists sequenced their DNA and confirmed what many owners already believed to be the case: Each baby crayfish was a clone of its mother, and they were filling Europe's fishtanks at alarming speed. Just 25 years ago, the marbled crayfish did not exist at all. Now, they can be found in the wild by the millions in Germany, the Czech Republic, Hungary, Croatia, the Ukraine, Japan, and Madagascar.
Grab a really big pot, and some seasoning, I'm hungry.
Wait. They're all clones, right ? I bet a single virus could wipe them all.
In Soviet Russia, our new overlords are belong to all your base.
There's a quick, easy solution to this.
How do they taste?
Wait. They're all clones, right ?
I bet a single virus could wipe them all.
It means they're more susceptible to all being wiped out by a virus; but, clones aren't necessarily 100% identical though. Mutations still happen. We're all descended from organisms that "cloned" themselves after, all. An isolated individual that wasn't hit by the virus could quickly repopulate.
"That's the way to do it" - Punch
It will be interesting to see what happens. Sexual reproduction is critical for spreading favorable genes like resistance to predators, poisons, etc. Since these are all clones they aren't going to have those advantages and sooner or later will encounter some factor that wipes them out. Apple farmers face a similar problem since each variety is a single genetic variant that is grafted onto other trees.
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Cloning is the most ancient form of reproduction. It's so simple and easy to implement. Sexual reproduction is much more complex, but took over for complex species because it allows individuals of a species to all differ slightly in every characteristic. When facing environmental stresses, these small differences show up as lesser or greater reproductive advantage. In a sexual species, any reproductive advantage means swift adaptation of the species to new environmental conditions.
These asexual crayfish (Procambarus sheldoni?) may be reproducing fast now, but like the Cavendish banana, they will be apt to succumb to some disease that a sexual species could adapt away from.