Talk:2608: Family Reunion

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How are relatives related by asexual reproduction defined and named?

While False (talk) 21:01, 18 April 2022 (UTC)

Any particular organisms in mind? It seems like you'd still have a generational parent, but there are a number of forms of asexual reproduction, blurring the line of what is a new lifeform and what is part of the old. Many plants, for example, can spread via colonies of their roots, whether severed from each other or not. I'm curious if there are organisms with more than two parents, and how many generations out of sync those parents can be. I think some plants might do this as well. 22:06, 18 April 2022 (UTC)
Look up mitochondrial donation for a case of three parents in humans, with two of them being the regular genetic parents for the 23 chromosome pairs and one extra parent (mother) for the mDNA. In nature you also have cases of horizontal gene transfer (for example via plasmids) where genetic information is passed outside of linear inheritance. 12:59, 19 April 2022 (UTC)
For the above case the definition would be a bit tricky, but for asexual reproduction each time the organism reproduces/goes through mitosis would be considered one generation I suppose. That does solve the _cousin _-removed thing, although perhaps not anything connected to which side of the family (maternal, paternal, etc). Then again those things aren't comprehensive for humans either, so bacteria certainly would be new. Wielder of the Staple Gun (talk) 00:25, 19 April 2022 (UTC)

This suggests humans have a common ancestor no earlier than 3000 years ago or so, due to inbreeding. So if we assume 20-25 years per generation, that works out to a max of 120-150th cousins. 

This is an important comic in xkcd lore

If the chair is made of wood, doesn't it mean that it's made of the dead remains of another relative? Isn't that rather gloomy?

Eje211 (talk) 21:30, 18 April 2022 (UTC)

"Good old Umpteen-billionth-cousin oaktree has practically become part of the furniture!" 22:00, 18 April 2022 (UTC)
If it is made from coal or oil-based materials, it might just be a great * (10^7) grandparent (or 1.7 * 10^8 cousin, 10^8 times removed). Cwallenpoole (talk) 13:16, 19 April 2022 (UTC)

Siblings would also technically be zeroth cousins, and the self would be a negative first cousin. No idea what higher order negative cousins would imply. Incidentally, the this structure fixes the lack of a gender neutral term for uncle/aunt/nephew/niece, who could be referred to as zeroth cousins, once removed. This does remove the directionality of the terms, though. 22:09, 18 April 2022 (UTC)

Higher order negative cousins would require that you are both descended from one of your own descendants. This either requires time travel, as in "All You Zombies", or counting step-parents, as in I'm My Own Grandpa.-- 22:22, 18 April 2022 (UTC)
Siblings share a parent, which is already a explicit disqualification from any 'cousin-counting' process. As is the <nephew and/or neice> to <aunt and/or uncle> relationship (via a parent of the latter party, though extend that minimal leg of relationship just one generation further and you get your archetypal first-and-zero cousins).
Yes, it would be nice to have a good term for that, but we already (in English at least) don't have a good word for "aunt/uncle/nephew/niece-by-marriage" unless you start to add "-in-law" to it (which itself is open to certain vagueness.
Though some languages do a lot more than English. 22:35, 18 April 2022 (UTC)

According to a family tree app we have, I'm my own 9th cousin once removed. 02:16, 19 April 2022 (UTC)

What about the drink on the chair? Assuming it might be an alcoholic beverage, would the bacteria and/or yeast organisms which catalysed the fermentation not also have to be considered as (very) remote relatives? Captain Nemo (talk) 09:52, 19 April 2022 (UTC)

Not to mention the fruit (or possibly grains, though the drawing suggests wine). Troublingly, every part of the meal except salt would have to be counted, too. 16:34, 19 April 2022 (UTC)
Water wouldn't be counted as well. 22:01, 19 April 2022 (UTC)
Yeast, yes, and as a member of the fungus "kingdom" that's a closer relative to us than plants. See 1749: Mushrooms. 17:17, 19 April 2022 (UTC)

According to TimeTree, Felis catus and Homo sapiens diverged about 95 Mya. This gives a mean generation time for the 17,000,000th cousin of just over 5 and a half years. Cats can expect their first litter at 15-18 months but probably lived ~5 years through most of their recent history, so say the average generational time is 3 years. Between that and the generation time of humans until recently, 5.5 years for most of those 95 million seems plausible. 18:22, 19 April 2022 (UTC)

OTOH, about 1,500 Mya for the aspidistra/human divergence yields a 3.5 month generation time, which seems low :-) 18:27, 19 April 2022 (UTC)
I actually wrote a new section earlier (like a Trivia section, about 'what we know and what we don't', but I forget now how I worded it) going through the Cueball-to-Other relationships in order of greatest to least proximity-of-relation, and gave the basic relationship and then introduced caveats ((that we don't know there are not unknown "removed"s, other than the states cat one (almost certainly the plant, especially!); the issue of age-disjointedness/re-convergence; that going back to Hairbun's common-ancestor (1024 (g^8)-grandparents) you likely get multiple MRCAs and/or single people in multiple positions in one person's ancestry; etc)).
There is nothing to say that the removedness is on the cat's side (felis/homo common ancestor might have spawned pre-homo generations that cycled quicker than pre-felis ones, though in recent times we do know that the typical age of primigravida is of course far less in cats so they could be heading back towards zero-removed, if so) and evidence is sketchy about even the early-hominin situation, never mind the creatures that came of the initial divergence. But the wide uncertainty certainly comfortably allowed the generational assumptions that the given figures seem to suggest. Yes, there were many, many words. But I made more effort to be economical than I have just now.
I was about to do the same with the plant when I tried a Preview submit which crashed things (or just happened to coincide with an unrelated browser hiccough, prob.) and I'm afraid I didn't have the heart to redo it from scratch. So I never actually got into the details of cross-Kingdom inter-relationships from extreme archeohistoric times, or try to work out which side might have been the shortest chain back to the MCRA (some current plants can live a long time, generating viable seedlings after centuries, but others also repropogate their seeds extremely rapidly!).
I've a feeling that the comic's assumptions would sit well within the huge uncertainty, and probably is based upon the general concensus of the top few expert papers presented upon Randall's idea-inspired trawl through the peer-reviewed literature. Or maybe just the one rather fanciful academic source that spontaneously generated the spark of inspiration that led to this comic... ;) 19:07, 19 April 2022 (UTC)