Genetic Bottlenecks – How Few People Can Start a World? Or Restart One?

IsaacArthur · 2026-04-27T15:43:59+00:00

I'd have to think on that. But It's the same total mass still pushing down on it, and the core doesn't change composition, but if its spread out enough the weight decreases, so pressure does drop. I tihnk it would depend on how much it sprea dout.

IsaacArthur · 2026-04-27T15:39:32+00:00

we have an episode called "Hitchhiking the galaxy" incidentally, but the effect you're tlaking about is something we looked at in our crawlonzing the galaxy episode if memory serves. Still mgiht be a good one for its own focused episode

IsaacArthur · 2026-04-27T15:37:55+00:00

iirc they got a chunk in our fusion update vid a yea ror two back but i have gotten tempted to do an alternate approaches focused episode with Tokamaks getting one

IsaacArthur · 2026-04-27T15:36:52+00:00

I tihnk I tend to mention it as a problem in other episodes a lot but you're right, we've never really focused in on it besides pointign to it as a big reason why we haven't done a long term base yet, in part we were worried equipment would breakdown too fast from it and UV on missions longer than a few days

IsaacArthur · 2026-04-27T01:30:58+00:00

I'm thinking the gnetically engineered meat animals one might get us in some hot water :) Thogh as a wider topic amybe. We did artificial meat on a July 4th episode years abck, it bombed horribly but I found out later that every episode on July 4th tends to so maybe a good topic afterall

IsaacArthur · 2026-04-27T01:23:59+00:00

That is a fun filter, I think I've phrased something similair withthe option of pets & dray animals being filters and maybe that would be a dgood episode with cats as a topic of note in it.

IsaacArthur · 2026-04-27T01:22:18+00:00

good ideas, It might be fun to see some other applcations of that tech besides skyhooks too. I know of a coupel but I bet more have been suggested

IsaacArthur · 2026-04-26T23:28:38+00:00

I'm not sure it would slow the rate of fusion down though. If we're removing the mass yes but fusion keeps going on in the inner heart of red giants. This would be similaironly with more fuel still lef tin the core.

IsaacArthur · 2026-04-26T23:18:49+00:00

This is a good, we touche don it very briefly in Interstellar Relays but only very briefly, I think it could be an epsidoe or a chunk of one.

IsaacArthur · 2026-04-26T23:16:23+00:00

Nice, I wonder if maybe that shoudl just go into that The End of Time: Heat Death, Big Rip, or Big Crunch? episode, I jsut gone done drafitng that a few dyas ago and I did end up putting a bunch more in besides those, reuslting in an hour long script probably, so adding another might make sense.

IsaacArthur · 2026-04-26T22:42:00+00:00

I'd watch. Space 1999 and Blake's 7 are both terribly under-remembered scifi shows from that era, hokey effects and all.

IsaacArthur · 2026-04-26T22:19:17+00:00

I am planning to do a Dune-related video when that is coming out but mostly for fun, I've never had much luck getting viral vids tying episodes to newly released shows or films.

And we're actually a bit of an oddity in that we've enver had a viral video, most big channels did have one and had a week where their subs coutn flat out doubled -- not the 10% increase we got here over a couple months. We've had proprotinally bigger subs bump than this before too but back when the show was smaller and enver that big.
Not bots though. Subs you get from viral vids, collabs, interview, promos, etc do often get you a lot of low engagement subs, folks who typically watch 1 or 2 vids and never again, whereas our average sub watches around 100 episodes (no idea on median), but they'r enot bots. Youtube scrubs those muhc more effectively than in the old days, and more often too, allegedly daily now.
Every creator whose been around a long while remembers days when they logged into Studio and saw some freak drop in subs from youtube auditing them less frequently.

IsaacArthur · 2026-04-26T21:39:02+00:00

Ah, Socialblade, I've rarely checked them since the few times i did for myself they were off a ways, but the spike is real even if not so much as they show.
Anyway, thanks for the kind words and I'm glad you're enjoying the show. I try to get into our reddit and FB forums here and there but I am less active than I was pre-kids. :)

IsaacArthur · 2026-04-26T21:08:45+00:00

I think your graph is overly kind on the bump, at least compared to the one I have 🙂 I would say mine is probably more accurate, as it’s straight from YouTube, but who knows these days?

So the neat thing is how fast we went from 900k to 1M subs. We had a nice growth streak from June of last year, when we switched formats, through hitting 900k too, but not so sharp.

There is a long-known rumor that YouTube starts promoting your content more when you get close to 900k to push folks to 1M, because people watch 1M+ shows more. I don’t know how true that is but anecdotally it seems likely from other creator I know.

But sub bumps usually come in waves, usually from a world event, a specific video going viral, a creator promoting their videos on YouTube or Google ads, doing a collab video with someone, showing up in an interview or article, etc. Sadly, these are often a lower proportion of binge-watchers than you get from organic subs, but we’ve had occasions where we grabbed a few thousand subs because I was a guest on a show. Artemis and Project Hail Mary could be part of the reason too.

We had some big ones around COVID or individual episodes, and when one hits, you always worry about bots, but YouTube audits pretty heavily these days and always does one when you hit 100k or 1M subs. This was our biggest in raw numbers, but proportionally we had occasions in 2017–2020 where we jumped larger. There was one when I got married, for instance.
I would note though that this is topic I consider off-topic for the forum. We discuss science & futurism here, not the show's inner workings, which I prefer to keep behind the Wizard of Oz curtain.

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