What Is Alive?

Life, the universe and everything is 42.
We try to define what life is and try to understand it better, but do these definitions really make sense?
So, without any further ado, turn on your imagination and lets go for a ride.

The Dictionary definition of alive: not dead, alert and active, animated.

The Dictionary definition of life: the condition that distinguishes animals and plants from inorganic matter.
Inorganic matter is something that is not carbon based(so not containing many carbon-hydrogen bonds).
So, according to this definition if its not carbon based its not alive. Substances like Gasoline(petrol) are primarily C-H bonds, so is petrol alive?
If gasoline is alive on the only premise of being carbon based then dead stuff is alive which is a contradiction.
Restricting life to carbond based sounds like a rather Earth centered definition. Why is life on Earth carbon based? Because things we classify as alive usually have DNA or RNA which are carbon based molecules that are mainly used for reproduction, and producing proteins.
What about noncarbon based life? Many people have pondered this question and Wikipedia has a nice summary of proposed ideas of what other based life might exist:https://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry

Is using water as a solvent part of being alive or is that also just a Earthling thing?
A solvent is a substance(usually liquid) that can dissolve other substances. So, aliens could easily use other liquids as their life solvent. This would also change properties of DNA(or RNA) and organelles in the cell because water is polar but if the life solvent is not polar other mechanisms would be used.

Current Scientific Definition of Life

  1. Ordered/have one or more cells:
  2. To have complexity.
  3. Metabolism:
  4. Is a chemical reaction to produce energy.
  5. Homeostasis:
  6. This is the ability to regulate chemicals, temperature, etc...
  7. Growth:
  8. Change over time.
  9. Reproduce:
  10. To make a copy(similar or identical) to ones self.
  11. Response:
  12. React to changes in the environment.
  13. Evolution:
  14. To adapt to the environment over generations.
Wait, mules cant reproduce so their not alive!?

Viruses

Viruses are not classified as alive because they can not reproduce themselves. They need to find a host to do it for them. They trick the host into copying their DNA or RNA to reproduce themselves.

Otherwise, viruses are alive. Or are they?

Fire Is Alive

  1. Ordered/has cells:
  2. Each flame is a cell.
  3. Metabolism:
  4. Like us humans, fire converts O2 and food into CO2 water and energy.
  5. Homeostasis:
  6. Fire regulates, once ignited it produces enough heat to keep burning. And if not given more food it will go into hibernation and only glow, trying to stay alive in the hope that it will find more food soon.
  7. Growth:
  8. A small flame can get bigger and higher if given more food and oxygen.
  9. Reproduce
  10. Fire typically starts of as one flame, but can than multiply creating more flames.
  11. Response:
  12. Fire reacts to its surroundings. If there is not much food it will go into hibernation and just glow. If there is a big supply of oxygen(because of wind for example) it will grow and reproduce a lot more.
  13. Evolution:
  14. Fire does not evolve. But it could be argued that it does not need to because it can easily be spawned. Also, because fire does not evolve it eventually dies out.

Rocks Evolve

They dont have metabolism but they do evolve. In different parts of the world there are different animals. For example, in Europe the squirrels are different from the ones in north America. With rocks it's the same thing. In different parts of the world there are different types of rocks. Like animals this is because of evolution. In places where water flows quickly soft rocks cant survive and get eroded. The environment shapes animals and forces them to adapt and same goes for rocks.

Who knows maybe rocks do have metabolism but just on a very long time period, so we humans dont notice.

Cars?

If Aliens Visit Earth We Probably Would Not Notice

In both science and science fiction there are theories that life on Earth started somewhere else, like on Mars for example. And through a giant meteorite impacts or other phenomenon got ejected into outer space and eventually landed on Earth.

But even if aliens landed on Earth today, we would probably not notice. We discover new species every year. So, if aliens landed in the jungle or the ocean we would think they are an undiscovered species.

When scientists talk about looking for life on other planets and moons they are really looking for Earth like life. There might not be human like life in our universe(or maybe multiverse) but there is most likely other life that is potentially very different.

Who knows maybe dust devils are actually ninjago ninjas.


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