The self-cloning marbled crayfish is a relatively new species, but the all-female crew is quickly multiplying.
According to National Geographic, the asexual creatures all have one female ancestor: the slough crayfish, a species often found in Georgia and Florida.
It all started in 1995, when a slough crayfish was taken from the Everglades to an insect fair in the U.S. For a reason scientists haven’t quite pinpointed yet, that slough crayfish became an entirely new species: Procambarus virginalis, or marbled crayfish.
When the crayfish began rapidly multiplying, the owner realized taking care of the offspring would be impossible, and took the crayfish to pet shops. Eventually, the pet trade made its way to Europe. Now, they're taking over the world.
"That one animal founded the whole species, and now we have billions worldwide," Wolfgang Stein, a neuroscientist at Illinois State University behind a recent study published in the journal "Nature Ecology and Evolution," said.
"They don't travel by themselves, but if you have one animal, essentially, three months later, you will have 200 or 300 offspring that are again clones of the mother and they will also reproduce within three or four months and have more babies," he told CBC.ca in an interview.
In 2007, the species was spotted in Madagascar. At that time, Stein said, they occupied an area about half the size of Rhode Island. In 2017, they’ve taken over an area the size of Ohio.
“That's a hundred-fold increase in just a decade,” he said.
For their research, Stein and a team of scientists sequenced the genome of about 12 marbled crayfish and found each rooted from the original female.
They also learned that the creatures had three sets of chromosomes, which may help the species adapt to diverse environments. Most animals have two sets, one from each parent.
But the research on marbled crayfish isn’t just fascinating. Researchers say it can help them learn a little more about tumors.
"What we see in slow motion with the marbled crayfish evolution is something that happens during the very early stages of tumor formation," Frank Lyko, a co-author of the study, told National Geographic.
Still, researchers noted that their understanding of marbled crayfish distribution and ability to adapt to diverse environments is "severely limited."
So, where in the world is this all-female gang of marbled crayfish now?
Stein said they’re in Japan, in Madagascar, in Europe, and also in the U.S.
Biologist Zen Faulkes from the University of Texas Rio Grande Valley is keeping track on his website with an updated map.
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