Just to preface, I’m a scientist: micro- and molecular biology. I’m not saying to take what I say as gospel, just giving context that I might know things. Sometimes.

Outbreeding depression has more possible implications than fertility decrease and infant mortality increase, entirely dependent on the heritable traits responsible for the depression effects. While the probability of persistent outbreeding depression seen in subsequent generationa would be lower due to traits subject to higher selective pressure, like increases in early infant mortality, the overall probability of outbreeding depression itself isn’t influenced post facto by its results, just its persistence.

Given we don’t know the original extent of neanderthal/human interbreeding, what we’re seeing now COULD be the “much lower percentage” you mention and still could come from multiple events. In fact, if these crosses resulted in stronger depression effects, I’d argue a greater number of crossings would be one factor behind the persistence of some genes today.

There ya go. It almost has too many squares.

Two ways.

First, sex chromosomes. In mammals, sex is determined by the sex chromosomes - males have XY, females XX. If interbreeding was equal between the sexes of both species, this would be reflected in the frequency of neanderthal genes on each chromosome in the current human population, but it’s more heavily skewed toward the Y chromosome than we’d expect if equal pairing was true. This suggests a higher proportion of successful male neanderthal/female human offspring.

Second, mitochondrial DNA. While genomic DNA in a sexually-reproducing species is a mix between the parents, in most mammals the inherited mitochondrial DNA (mtDNA) is purely maternal. This is because only the egg’s mitochondria typically survive, though on rare occasion paternal mitochondria are also passed on. There is no known existent neanderthal mtDNA in the human population. This suggests either female neanderthal/male human crosses didn’t happen much and/or didn’t often produce offspring capable of further reproduction.

Of course, there are many other explanations for all of these. These are just amongst the simplest possible options, and in population genetics, it’s not uncommon that the simplest answers are frequently correct.

Keep in mind heterosis isn’t always the result of hybridization and even then the magnitude of isolation doesn’t always positively correlate. Outbreeding depression can also be the result, increasingly so when two groups are more genetically distant or when one group is already subject to heavy inbreeding depression, as the neanderthals were thought to be.

Anecdotal, but… I’ve been a musician for 36 years and have fantastic hearing not just for my age but for any age. I know, I have to get it quantitatively tested twice a year!

I can’t tell the difference at all between FLAC and 320 kbps from the same source. I can tell a difference between FLAC and 128 kbps, but it’s not huge. It sounds a bit dull, but I have to be looking for the difference and comparing the two. If you just gave me one or the other with no reference, I might suspect the 128 if it was a simple recording of a single instrument or a song I’m intimately familiar with, and even then I wouldn’t be sure of it. It just sometimes “feels” weird.

So I converted over 4 terabytes of my music stash to 320 kbps and cut the total space into less than 2. Feels good.

I couldn’t agree more. I got interest in higher-end audio equipment when I was younger, so I went to a local audio shop to test out some Grado headphones. They had a display of different headphones all hooked up to the “same” audio source.

60x vs 80x sounded identical. 60x to 125x, the latter had a bit more bass. 125x to 325x, the latter had a lot more bass and the clarity was a bit better. Then I plugged the 60x into the same connection they had the 325x in. Suddenly the 60x sounded damn similar. Not quite as good, but the 60x was 1/3 the cost and the 325x sure as hell didn’t sound 3x better. They just had the EQ set better for it.

Appreciate you linking in your blog post. I’ve been on the fence about Kagi and you bring up a lot of good points informed by sources I’m unlikely to delve into.