Not only do they evolve, they evolve more rapidly than any other creatures we’re aware of. A virus can mutate almost immediately, whereas other animals require millions of years to display those sorts of dramatic changes.
Comment on Smug Viruses
sp3tr4l@lemmy.zip 2 weeks ago
Oh, they’re can spend long periods of time being inert, and then resume activity when conditions change to be more favorable?
… Like a tardigrade? Or a seed?
Oh, they cannot reproduce themselves on their own or within their own species?
… Like a obligate parasite wasp? Or a plant species that relies on a pollinator?
Oh, they do not reach a stable equilibrium within their ecosystem?
… Like humans?
I’ll give you that viruses never metabolize and are not capable of homeostasis… but they do not lack ‘any’ of the characteristics of life, they have some big ones.
They reproduce, evolve, and respond to stimuli.
Anticorp@lemmy.world 2 weeks ago
Tlaloc_Temporal@lemmy.ca 2 weeks ago
Complex organisms can also drastically change from point mutations, although such changes are more likely to kill the organism as they grow more complex. Viruses are so incredibly simple and make so many copies that this doesn’t matter.
Many organisms can hybridize, which can make drastic changes with much less chance of fatal errors. Plants especially like this; see farmed maize vs wild maize or the entire brassica genus.
Viruses also hybridize though, and can do so much more drastically. Most of the critical genes are in the host, so virus genomes are free to do whatever, and because they highjack other genomes a very small change can radically alter their behavior.
BakerBagel@midwest.social 2 weeks ago
This virus on it’s own is absolutely useless and can’t adjust to it’s environment at all. A parasitic wasp is still a seperate entity that has it’s own cells and genetic material that covers all basic function of a living thing. A virus is literally just a protein coat protecting a bit of genetic material. A parasitic organism is still doing cellular metabolism even if it isn’t in a host organism, but a virus isn’t.
barsoap@lemm.ee 2 weeks ago
Of course it adjusts to its environment – it even uses it to replicate. Viruses are that branch of the genome which is being minimalist about its seed pods, other branches need all kinds of superfluous stuff like eyes and limbs and brains and whatnot. Complete waste of resources, having pods which can maintain independent homeostasis, what good does that for the homeostasis of the genome? Eh?
BakerBagel@midwest.social 2 weeks ago
Viruses make the simplest prokaryotes look complicated. A bacteria has ribosomes to read nucleic acids to make proteins and enzymes. That’s the cellular metabolism that a virus actually lacks. It’s not a matter of calling a person a living thing while their cheek cells aren’t. You can take human tissue sampes and culture them indefinitely if you wanted to, because those cells are still undergoing cellular metabolism, taking in resources and excreting waste products. A virus doesn’t even have the ability to read it’s own genetic material. It’s a hostile instruction manual.
barsoap@lemm.ee 2 weeks ago
It’s a hostile instruction manual which learns, adapting itself to its surroundings, constantly re-writing and re-inventing how it interacts with the world. Which is more than can be said about most politicians. Forget about physical anatomy, for a second, and consider the species as an organism.
Tlaloc_Temporal@lemmy.ca 2 weeks ago
And yet, that wasp will die out in a single generation if it’s host disappears. It does most of it’s own processing, but it’s existence is still contingent on a specific host species. Does that make parasites less alive than other life?
Many insects go through a phase of their lives without a mouth or stomach. They can’t eat at all and quickly starve. Are they less alive?
Most life would die out if the sun stopped shining. Does that make chemotrophic organisms more alive than phototrophic life?
Chemotrophic life still needs chemicals to eat, and are completely useless without them. Does that make a Boltzmann Brain the most alive thing possible, coming into existence without any outside action whatsoever?
Plants depend on the sun for energy, animals depend on plants for carbohydrates, we depend on animals and plants for carbs and proteins, mayflies depend on stored energy from their larval stage, parasites depend on other organisms for transportation, food, protection, parenting, and even homeostasis. Viruses depending on other cells for reproduction doesn’t seem out of place to me.
BakerBagel@midwest.social 2 weeks ago
Consuming resources is a definitive characteristic of living things. Scienctists had to define what life is and viruses just don’t click enough boxes. It’s the same as astronomers determining what is a planet vs a dwarf planet vs an asteroid or mathematicians deciding that 1 isn’t a prime number. There has to be a hard cutoff at some point.
Viruses are rogue genetic material that insert themselves into a host cell and hijack all it’s processes and metabolism. Calling them a living thing is like calling malware a computer, or a joke between friends a movie.
Tlaloc_Temporal@lemmy.ca 2 weeks ago
Ah, a definition of life in Namibia for a grade 12 course. Quite the scientific authority you have there.
Here’s a short paper (Origins of Life and Evolution of the Biosphere 32, 387-393, 2002) that refutes your position that a single definition of life is definitively agreed upon.
Here’s a paper (Synthese, 2012) on how a definition of life is impossible and pointless.
There is a species of dog that infects other dogs as a parasite. There are viruses with larger genomes than some bacteria. Obligate parasites and endosymbiotes often lose large portions of their genome and depend on their hosts for their vital functions. Nature doesn’t care about are definitions, and biology hates hard cutoffs.
angrystego@lemmy.world 2 weeks ago
Thank you for making the perfect reasonable and easy to understand points! Creatures with parasitic strategies have so many times been misunderstood due to they’re reduced bodies and functions. Viruses are the same case.
WolfLink@sh.itjust.works 2 weeks ago
xkcd.com/2307/
Rubanski@lemm.ee 2 weeks ago
Prions are just fucking terrifying