My whispering breath lingers ever so slightly onto the foggy, cool glass window of the laboratory. The condensation creates a kaleidoscope of the canvas, making caricatures of the bustling campus outside. With hot tea in hand (I have a cold) and eyes set on my babies, I contemplate the meaning of life.
My smile is bright enough to startle my children. I gaze into their eyes and pick up the one shivering in the corner. The mouse’s tag reads 1492. The hand he has come to know so well scoops him up from the cage. His rapid heartbeat generates a metronome for the cello concerto I am listening to. The sound waves of the piece ricochet off the pearly white walls of the laboratory as I waltz to the beat with furry friend in hand. Thump. Thump. Thump.
Have you ever listened to the pulsing of the universe with your chest? Holding a mouse to your heart is not unlike hearing the sea through a conch shell. My mind leaves Chicago, the resonating notes of the cello are imperceptible, and the only sound I hear is that of two hearts. A linkage that reminds myself of the vital life force interspersed through all living things.
“What is life?” I say again to myself, this time staring at my arms and hands. The hot tea clears the congestion in my lungs, but its effects are not enough to deter my imagination from growing wild. I envision clusters of RNA packed protein capsules making home in my body, injecting long strands of their icky genetic material into the healthy cells lining my esophagus and throat. I’ve always been told that viruses are nonliving, though secretly I have always disagreed with this fact. Perhaps the definition of life ought to be changed to encompass viruses as well, who are very much living to me as they take over my body.
Though I have come to resent viruses at this moment, my mind circles back to an article I read for biology class titled “Darwin’s Surprise”. The article claims that endogenous retroviruses have long been with us throughout the centuries, even endowing within us special properties (like the ability to give birth to children using a placenta instead of an egg). It turns out that the cells lining the placenta are “parasitic” in nature, attaching themselves to the uterine wall of the mother.
If that wasn’t cool enough, scientists have been playing with dead viruses in our genomes to revive them. Oh yeah I forgot to tell you. We have dead viruses in our genomes. (Dead viruses?? But I though viruses weren’t living?) Well, non-functioning viruses. Apparently, we’ve been at a genetic warfare with these protein-capsuled particles for millenia. Many have lost their battles with us, but a few lucky ones took a ride by infecting our reproductive germ line cells. And the rest is history (and as it turns out, our existence). The infected germ cells mitosisized (mitosed? mitoticized?) to created infected gametes (from a male and female respectively, of course), which then combined to make infected zygotes. Here, the zygote often died, but if it survived, then the entire zygote was infected with the virus.
Remember, the environment and the environment only can determine if a certain gene or protein is advantageous to an organism. So while the viral genes in our ancestors could have been harmful, they have now become useful for us as the environments have changed and the viral particles have mutated.
Let’s get back to the crazy scientists reviving viruses (and where can I sign up?) These scientists took the phrase “When life gives you lemons, make lemonade” to heart when thinking of ways to stop HIV. They saw how fast HIV replicated and knew there were bound to be many genetic mutations along the way. So, they thought to themselves, if the virus loves replicating so much, why not turn the dial up to 10x as fast and see how they like it! What boggled my mind next was that their method worked. They sped up the replication of HIV so fast that the number of mutations overwhelmed any progress of infection. Pretty cool, huh?
Darwin would very much be in surprise if he knew what we were doing, but he would most likely encompass viruses when discussing descent with modification in the “modification” realm. Although he spoke of the environment as the modifier of organisms, by reading this article, I believe he would put viruses in the bucket of “environment”. After all, they are nonliving right?
I don’t think that things are “living” or “non-living”. Instead, I imagine a spectrum. Scientists long ago proved that there is no such thing as a “vital force” in organisms that allowed them to be alive when they replicated early-Earth environments and mixed primordial elements to make “life”. If life stems from the material (physical elements like atoms and bonds), then it makes sense everything has some amount of “life” to it, even rocks. I do think there are thresholds to the amount of “lifeness” of an object, such as if an object has the right amount of stuff to replicate versions of itself. In this case, it has passed stage 1. We have the ability to do that, but also speak and remember, thus I would put humans at stage 4 or 5, while starfish would be stage 2. Viruses would most likely be stage 1 of life.
I also disagree with the notion that there are “seven signs of life”. I think it is unwise to define life based on relatively superficial attributes like order or reproduction. Should we define a “knife” as an object with a blade and hilt, or anything sharp enough to cut? What if a knife can’t cut? Is it still a knife? What makes a knife a knife? Similarly, should we define life as objects that have order, cells, use energy, respond to environmental changes, regulate, grow, reproduce, and evolve? Since there are exceptions to these “signs” (like viruses), imposing a rigid rule on what is life and what is not limits your horizons. Unlike laws of thermodynamics, the “seven signs of life” is not all encompassing of the universe. This model of life may work now, but like the outdated Monera, I believe this rule of life will become outdated soon.
Nonetheless, viruses are very much living to me. As I drink my tea and brace my cold, I can’t help but laugh that I am made possible by the very same type of particles causing damage to my body.