Free Republic

Over the last few decades, the planet has been at the mercy of a ten-legged, many-clawed crustacean ravenously creating a clone army bent on world domination. No, it isn’t an interplanetary interloper or the result of an uncontained government experiment. This is biology gone wrong, or if you happen to be a marbled crayfish, biology gone horribly right. What’s unusual is that instead of the expected two copies of their chromosomes, marbled crayfish have three. Their genetic composition is similar to the Slough crayfish, a close relative, leading scientists to conclude that the first marbled crayfish was born through an...

The marbled crayfish is the only crustacean that reproduces asexually, with the all-female species making clones of itself from eggs unfertilized by sperm... Since its discovery in 1995 in Germany, the marbled crayfish has spread across Europe and into Africa in huge numbers. “They eat anything—rotten leaves, snails or fish broods, small fish, small insects," says Frank Lyko, a molecular geneticist at the German Cancer Research Center in Heidelberg. “This crayfish is a serious pest,” ... Lyko and his colleagues sequenced genomes of about a dozen marbled crayfish from different parts of the world and performed less detailed genetic analyses...