Naked Science Forum
Life Sciences => Plant Sciences, Zoology & Evolution => Topic started by: steelrat1 on 10/02/2023 15:06:12
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My question is, the timescale of living things, we have the Mayfly — The Shortest Lifespan and The Greenland shark is recognized as one of the longest-living animals on Earth, but its lifespan of up to 500 years, non-animal is Methuselah, a bristlecone pine in the White Mountains of California, stands at the ripe old age of about 5,000, but could anything be classed as living i.e. birth, growth, reproduction, and death. Be applied to other forms of life for argument’s sake Crystal based life, something that takes millions of years in a life cycle of birth, growth, reproduction, and death. Or is life just based in human time life spans?
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The "essence of life" is either philosophical bullshit or the capability of an entity to extract chemicals and energy from its environment to produce and repair its own structural material. Reproduction is not a necessary characteristic as there are plenty of sterile plants and animals that are clearly alive.
Even then, it's a somewhat fluid concept that doesn't completely distinguish between a virus and a crystal unless you include a requirement for the replication of nucleic acids, which puts viruses slightly on the "life" side. That requirement at least covers long-lived sharks and plants.
As far as we know, life has only evolved on one wet radioactive planet. Water seems to be essential: the hydrogen bond is the key to nucleic acid replication. But ionising radiation can induce defects in nucleic acids so it is unlikely that the DNA of a very long-lived entity would remain sufficiently stable for the entity to be indefintely recognisable as the original.
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ionising radiation can induce defects in nucleic acids
There are some very hardy critters which can stand high levels of radiation.
Deinococcus survives 5,000 Greys (5 Greys will kill a human)
https://en.wikipedia.org/wiki/Deinococcus_radiodurans#Ionizing-radiation_resistance
5,000 Greys will kill half of tardigrades:
https://en.wikipedia.org/wiki/Tardigrade#Physiology
One reason elephants don't die of cancer at a young age is because they have 20 copies of the P53 gene that detects and destroys cells with DNA damage (compared to 1 in humans).
https://en.wikipedia.org/wiki/Peto%27s_paradox#Evolutionary_considerations
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Admittedly so, which is why the survivors of World War III will be cockroaches, a more intelligent species than the one that begins it.
But individual Periplaneta, Deinococcus and tardigrades do not live for very long compared even with humans. So whilst their species will eventually inherit the earth, no individual is likely to celebrate its 5000th birthday.
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My question is, the timescale of living things, we have the Mayfly — The Shortest Lifespan
Mayflies live about a year. It's just that they don't last too long after puberty, not even retaining the means to eat.
As for long-lived things, every amoeba is arguably tens of millions of years old. They're not born, so its hard to define when they 'started'. Just saying, not everything goes through the steps of birth, growth, repro, and death.
Many creatures have aging and death built into their genetic makeup, including us. It was an evolutionary adaptation that made the species more fit.
Or is life just based in human time life spans?
Don't know what you mean by this. Is it measured in terms of human life spans? No, it's usually measured (by us) in hours, day, years, or more standard (to us) units of time like that. I don't think you're asking that, but I cannot figure out what you actually are asking.
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every amoeba is arguably tens of millions of years old
Scientists were surprised that life survives deep underground.
It is thought that the metabolic rate there is 10,000 to 1 million times slower than at the surface, with individual amoeba cells dividing perhaps once in 1,000 years.
It is thought that 90% of Earth's bacteria & archaea live in this deep underground zone (not at the surface, which is what we are normally exposed to).
This may provide some indications that life could exist elsewhere in our solar system.
https://en.wikipedia.org/wiki/Deep_biosphere#Living_with_energy_limitation
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My question is, the timescale of living things, we have the Mayfly — The Shortest Lifespan
Mayflies live about a year. It's just that they don't last too long after puberty, not even retaining the means to eat.
As for long-lived things, every amoeba is arguably tens of millions of years old. They're not born, so its hard to define when they 'started'. Just saying, not everything goes through the steps of birth, growth, repro, and death.
Many creatures have aging and death built into their genetic makeup, including us. It was an evolutionary adaptation that made the species more fit.
Or is life just based in human time life spans?
Don't know what you mean by this. Is it measured in terms of human life spans? No, it's usually measured (by us) in hours, day, years, or more standard (to us) units of time like that. I don't think you're asking that, but I cannot figure out what you actually are asking.
What im asking is would a mayfly experience time the same way a human would in his/her lifetime? if the mayfly lives for only a day, a perceived lifetime almost?
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What im asking is would a mayfly experience time the same way a human would in his/her lifetime?
A mayfly doesn't know what a second is, but a mayfly and a human both experience a second as a second.
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What im asking is would a mayfly experience time the same way a human would in his/her lifetime?
A mayfly doesn't know what a second is, but a mayfly and a human both experience a second as a second.
But the mayfly second is longer. Its why flys react faster.
https://www.theguardian.com/science/2013/sep/16/time-passes-slowly-flies-study