I was wondering what some of the oldest living organisms are. I am especially interested in what some of the longest-living insects are.
Bristlecone pines (Pinus longaeva) can reliably get up to 4700+ years old, two bristlecone pines in Nevada are thought to be ~4.7 thousand and 4.9 thousand years old (link). A pond cypress (Taxodium ascendans) was over 3,500 years old until it burned down when someone tried to smoke meth inside it (true story). There are some clonal groves of trees that are thought to be 10,000 or more years old. King Clone, a clonal creosote bush in the Mojave desert, has been confirmed by at least two methods to be over 11,700 years old.
Among invertebrates the ocean quahog (Arctica islandica) is known to live over 400 years. Some crustaceans such as lobsters can live more than 100 years. There is a spider in Australia (Gaius villosus) that lived 43 years before dying (link). There are reports of a buprestid beetle that lived for 47 years before metamorphosing in the Guiness Book of World Records.
Among vertebrates Greenland sharks (Somniosus microcephalus) live in excess of 400 years and may not reach sexual maturity until 150 years of age. Bowhead whales can live up to 210-250 years of age. There are reports of an Eastern box turtle (Terrapenne carolina) with the year 1861 carved into its shell, and it appears that they’ve managed to track down people who knew the ones who did it personally, indicating that the turtle was over 150 years old at the time (link).
The one we all know: Galapagos tortoises can live to be up to 150 years of age, although that’s not much compared to the aforementioned organisms.
I don’t know the longest living insect, but some periodical cicadas live underground in immature forms for 17 years, and then surface to live out their adult lives in a month or so.
This is a question where one quickly has to define one’s terms very carefully. With insects, it is usually quite clear what an individual is, and how to define its age. But what about a tree that reproduces asexually, always putting up new trunks, until it is a whole forest unto itself? Is that a single individual, thousands of years old, or is each trunk an individual, generally only a few decades old? What about a bacterial spore that sits in permafrost for tens of thousands of years, then is thawed and lives for only a few days. How old is it? Even with insects, this question of how to define age can arise. If an egg is dormant for months, the larva develops underground for weeks, and the adult lives a few days, how old was the individual when it died? Tardigrade cysts, nematode eggs, plant seeds, fungal spores, etc. can exist for extremely long times with no detectable biological activity and “come back to life” when made wet and warm. I’m not saying there is no answer, I’m saying the answer depends on what you are willing to accept as “an organism” and what you accept as “longest living.”
Something interesting is that small bats, despite being small mammals with a very high metabolism, can have surprisingly long lifespans with several species recorded living in excess of 20 years and the record being a tiny Myotis from Russia that was tagged as an adult and recaptured 41 years later. It seems they don’t senesce the way many other mammals do.
I don’t think most people would consider spores or an egg a “living organism” as such. But with insects (as singled out by the original poster) one often doesn’t initially realize that their larval stage is by far the longest period of their life and they only emerge as adults for reproduction and then die relatively quickly - that beetle references by @russell_engelman an interesting case. Some Petaluridae dragonflies may live more than 10 years as larva.
You can check birds’ longevity list here: https://euring.org/data-and-codes/longevity-list
Greenland shark live up to 250 years but can live up to 500 years. You may wonder why is this so it is because they live in cold climate which means low metabolism .[
Adult tapeworms can live for 20 to 30 years.
The wikipedia page on the longest living organisms is actually one of the best written on the site in my opinion.
It provides a long list of possible answers depending on your philosophy of what being long lived means and what being an organism even means, plus lots of examples of the longest living organism of a particular species.
This is a complicated question without one single answer I think, and you could reasonably argue for as long as millions of years.
It’s sort of sobering that many of the oldest birds in that list were hunted (and, not what I thought were game birds, either).
I’m not that up on this, but I’ve long heard that parrots are very long lived:
Well, most of shot birds on the list are in fact ducks and chickens, so gamefowl, it’s different from country to country as in many European countries songbirds too were and partly is a normal food.
Yes, a lot are ducks; but I was surprised to see the herons and egrets that were shot.
They’re eaten too, though have no idea why would anyone want to, they eat fish.
In particular for ornaments on fancy hats.
The 100,000,000 year old oceanic endolith bacteria are the longest lived organisms in my opinion because they have never froze or stagnated, merely metabolizing extremely slowly
I think there are some underground fungus in the Midwest that cover a couple states and are sort of considered to be immortal. I cannot find the reference now, but here are some similar stories:
Reminds me of some old hippy song about whales from my youth:
And in the long run we will kill you
Just to feed the pets we raise
Put the flowers in your vase
And make the lipstick for your face
Tapeworms are cute