On the Swine Lineage of Minecraft
Co-researched by @squidwolfranger
We propose that the humble pig, or it's ancestor, originated from the Nether thousands of years ago and that studying it's lineage could glean insights into the nature of the undead plague.
Using @wordofdan previous work Swinization: The Tendency of Mobs to Develop Pig-like Forms as a baseline, we hope to disprove his original theory that pigs evolved independently. Also referencing @squidwolfranger essay Of Course Hoglins and Piglins are From the Nether, That's Obvious!
We know that Piglins and Hoglins are one of the few Nether mobs that aren't fireproof. An odd trait but it also means that a common ancestor between them and pigs isn't out of the question.
A much more significant difference is that pigs don't zombify on contact with Overworld air the way Piglins and Hoglins do. Which leads to the inevitable conclusion that the zombie plague is indeed airborne in the Overworld. But as that dimension still possesses living mobs it stands to reason that most mobs who have adapted to live there are immune to the airborne strain. Including Villagers and pigs.
Which is why I think that pigs came to the Overworld many thousands of years ago and over time evolved to live there as a naturally spawning mob. Thereby surviving the subsequent undead plague the ancient Overworld civilization unleashed on themselves. (Squid thinks that pigs are just Like That which... fair.)
Squid proposes that the greater ambient heat found in the Nether makes it difficult for airborne contagions to propagate. That is why the plague doesn't cross between dimensions. And it is also why Piglins are so afraid of zombie Piglins despite the latter's neutrality. They are the only naturally spawning carriers of an interdimensional plague.
The zombie plague's different effects on different mobs is exemplified by the three swine lineages. Piglins status is altered by the zombification process similarly to Villagers. Unlike them however, zombie Piglins aren't hostile. Indeed they are the only undead mob that isn't hostile.
Hoglin behavior does not noticeably change after zombification. Which means that other mobs might also simply be doing what they did before becoming undead. Personally, I believe the phantoms are the most likely candidates but that's besides the point.
And pigs represent the mobs that cannot become undead. Which includes all Overworld animals (except horses) most Nether mobs, and all of the End mobs.
(Side Note: is The End infected by the undead plague?)
Conclusion: pigs are the best swine mobs.