Complex critters are pretty clever. I’ve enjoyed watching David Attenborough and his “Planet Earth II,” in which he shows us some of the cleverness we may have overlooked:A fish sweeps up some debris, finds a clam, takes it to a round coral
and throws it again and again at the coral until it breaks open. Big dragon lizards bite an ox and wait weeks for it to die of the poison. Hippos in rivers and turtles on a coral shelf return to the same locale so fish can find them and clean their skin of small invaders.
Perhaps more amazing than these examples of living genius is the recently discovered trap that bacteria have “invented” in order to protect themselves from viruses. Somehow, sometime long ago, bacteria added a few repetitive genes to their genome. These repetitive genes were clustered, regularly interspersed, short, palindromic repeats of DNA (CRISPR).
They were first observed in E.coli bacteria in 1987 and again in 1993. Those repetitive sequences were recognized as being similar to the DNA of bacteriaphage, viral enemies of bacteria. The bacteria had copied them as traps, a kind of immunological memory, to fight off the similar invading viruses—the bacteriaphage. By adding the repeating virus-like DNA to their own genome, the bacteria could react faster to another attack of the virus, the way vaccination works in us.
During an attack, the bacteria copies the phage DNA, turns it into RNA that its enzyme Cas9 can destroy. (Cas 9 is not active unless it is bound to that “guide” RNA. This means that CRISPR/Cas9 can find specific genes (ie specific pieces of DNA) and try to repair them until a mistake is made and the gene is “knocked out.”
This is an amazing example of survival tactics at the molecular level. It raises the stakes big time for betting on life evolving wherever it gets half a chance. And half a chance may be all that our local solar system moons can manage, but we’ll soon know, if all goes well in the next decade or so.
Meanwhile, read Ben Miller’s book The Aliens Are Coming—The Extraordinary Science Behind Our Search For Life in the Universe, New York, the Experiment, 2016. Notice the subtitle. The author, a “mutant ape,” is a realist, as well as a “Comedian,” a brilliant writer who entertains us as he takes us into the complexity of life’s possible beginnings and how we are learning with “…technological marvels
returning unprecedented amounts of data…” that we may indeed NOT be alone in this universe.
Miller’s short sections, labeled with bold titles, help explain the nuances and intricacies of chemistry, astronomy and astrophysics, beginning with theories of how life may have started on Earth and how we might detect its presence in the exoplanets we are finding throughout our galaxy. Thrown in the text are lively explanations of entropy, earth’s extremeophiles, our oceans’ hydrothermal vents, space travel realism, Earth’s continental drift and the “aliens” it produced on
separated islands and the later convergence of animal intelligence in “completely different kinds of brains. (Example: apes and crows are both puzzle solvers.)
In short, I highly recommend this book to astronaut.com readers. Just be fore-warned: Ben Miller’s wit can catch you sideways. Better not take the title of the book seriously.
Author of The Archives of Varok
The View Beyond Earth (Book 1.)
The Webs of Varok (Book 2.)
Nautilus Silver Award 2013 YA
ForeWord IBPA finalist 2012 adult SF
The Alien Effect (Book 3.)
An Alien’s Quest (Book 4. Released Nov.21, 2016)
Excerpts, Synopses, Reviews, On Writing, Characters and More-
Reviews of significant books- http://www.goodreads.com/Cary_Neeper
How the Hen House Turns- http://www.ladailypost.com
Complexity, Bio, Bibliography and Links- http://caryneeper.com
Astrobiology- https://astronaut.com search:Who’s Out There