Concurrent evolution

Crabs have happened five times. We probably shouldn't be surprised by different lineages trying the same thing.

 

Some species mimic another, say one that's poisonous or venomous, to avoid being eaten.

 

where does the fiction come in to play?

 

Hmm... What is "Concurrent" evolution? Yeah, I know what the Convergent evolution is, like shark and dolphin both evolving to become excellent swimmers and having similar body structures but two species with totally different evolutionary linage.

 

From our human perspective all life on earth is contained on earth... But from the perspective of advanced civilizations that rarely, if ever, reveal themselves to humans, and who aren't limited by the massive distances between life sustaining planets, we're just another gardening bed they've been planting stuff in for a billion years.

 

My mind is blown, by the more plausible scenarios, for why we're here. Alien intervention not required.

 

Aliens could be existing all around us and we'd never know it if our perceptive abilities lacked the capacity to notice them.

Like the old story of someone who has never seen more than the moving shadows on the wall of the cave haven't the slightest clue that those shadows are actually people dancing around a campfire at the entrance of the cave. Or similarly when you show a conservative christian an ordinary photo with a small bit of nudity that's not in context with a more ordinary image, they lack the capacity to see that nudity because they object to the site of it in the first place.

 

If the aliens have been planting us, when do they harvest us?

 

Does the carrot really know what is happening to it when it's pulled up from the ground? Do fish perceive humans once they're hauled up out of the water by them? As in, we could be actively harvested as we speak right now and barely notice it. First thing we'd need to know is what they're interested in harvesting?

 

Fantasyland

 

"...if astronomers look for Dyson spheres around white dwarfs and come up empty, that can help estimate how many advanced civilizations may exist in the galaxy. Here’s how the logic works: Astronomers have only measured a small fraction of all the white dwarfs in the galaxy. But if enough aliens decided to build Dyson spheres around their white dwarf homes, then we should see at least one Dyson sphere in our surveys. If we don’t see any at all, then that sets an upper limit on the number of alien civilizations building Dyson spheres around white dwarfs. Of course there could be aliens who decide not to build Dyson spheres, or aliens that build spheres around other kinds of stars, but Zuckerman argues that over the age of the Milky Way the most likely outcome of advanced civilizations is to build a Dyson sphere around their white dwarf, and so we should focus our searches in that direction." https://www.space.com/aliens-hiding-on-dyson-spheres-around-white-dwarfs

 

the vacuum guy?

 

Freeman Dyson and James Dyson do not appear to be closely related.

 

Mimicry is often in response to predation risks, with a few examples of pollination sneakiness.

Convergent structural evolution is in response to limitations (or opportunities) in physical environments.

These are both convergence but one is pure biology and the other isn't.

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Linnaeus did not invent the idea that structural similarity implied relatedness, but he built on it. That, and inventing a 'You can't learn this, sucka' system of taxonomic mumbo jumbo. ¯\_(ツ)_/¯

Nucleic acid sequencing and 'workflow' are much better for sorting out relatedness. It went from being unknown, to known but possible, to practical but super expensive, to very very cheap in about 70 years. Other technical revolutions that have played out at about the same tempo could be listed. Roughly speaking they were concurrent across 20th Century. But that is the only concurrent in this thread.

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It seems implausible that nucleic acid sequences could mislead us about biological relatedness. I'll just leave it at that

 

Oyston et al. 2022 (our topic here) leans heavily on biogeography. Organisms living close by are more closely related. This seems a fine organizing principle, if not stretched too far.

It works on Earth because speciation by evolution is much faster than continental drift via plate tectonics. Might say 100x faster but better be vague about that.

When one drills down to single-celled organisms, speciation can be absurdly fast; like weeks. But only if you give them a very good reason to do so.

 

rod serling, that was a good one

To_Serve_Man_(The_Twilight_Zone)