Squids and Octopi Continue to Baffle (and Amaze) Scientists
Many marine biologists continue to be enamored with the study of Cephalopods, in particular squids and octopi. In early April 2017, researchers discovered something even more alien about these baffling creatures: they can edit their DNA.
In a study published in Cell, an academic journal, Joshua Rosenthal’s published his work and insight on the RNA editing abilities in squid. First, let's have a quick lesson on how MOST creatures DNA works: typically RNA acts as a middleman in how DNA makes proteins and faithfully transmits the message in the genes. And, typically, these creatures have no say in how it is transmitted. Except, as it comes to light, octopi, squids, and cuttlefish can change or edit the message that gets read out to make proteins.
This is particularly interesting because it seems to be the reason behind their slow evolution. The article in Cell goes as far as saying that this editing process lead to "positive selection of editing events slows down genome evolution.” Rosenthal adds, "Editing is important enough that they’re forgoing standard evolution,”
What is even more interesting is the fact that most organisms posses the enzyme needed for gene editing. However, it just isn't widely used. One of the largest reasons it isn't used is because it can cause more damage than it does good. Scientists have investigated it, but, according to an article in Wired, largely abandoned the research into it, as it wasn't entirely worthwhile.
Queue Rosenthal and his team of researchers. Squid DNA/RNA first became of interest to him because he realized it was a little bit different each time he looked at it. As Wired says, "Where the genetic material of humans, insects, and other multi-celled organisms read like a book, the squid genome reads more like a Mad Lib."
However, the conclusion of the article in Cell presents only a hypothesis: that these creatures used DNA editing to maintain a more complex brain structure instead of going through a natural evolutionary process. It is this brain structure, likely a product of RNA editing, that allows these animals to do all the amazing things they are well-known for: camouflage themselves, using tools, solve puzzles, and even communicate.
The above image comes from Flickr user damn_unique and is liscensed under Creative Commons 2.0.