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MLA Full: "You Need to Know About This Ridiculous Fish." YouTube, uploaded by vlogbrothers, 5 July 2019,
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APA Full: vlogbrothers. (2019, July 5). You Need to Know About This Ridiculous Fish [Video]. YouTube.
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I got to see an Ocean Sunfish (Mola mola) up close and personal at the Monterey Bay Aquarium recently and I fell in love. These things are the superlative of superlatives. They are the biggest bony fish, they lay the most eggs of any vertebrate, and grow the most from egg to full size of any vertebrate. Yes, they're silly looking, but the whole thing about evolution is, whether we can figure out why or not, things don't survive if they aren't good at /something/.

Sea turtles and mola mola, despite having deeply different lineages, actually share a lot of characteristics. They have the same shaped flippers, they both have beaks, they both rely on their size to protect them, and they both create lots of babies in the hopes that only a few will survive (though, Mola mola take this to a different level.) They're also both basically the same shape, which is super weird.

And here's a wild thing, even though sea turtles evolved from land-dwelling reptiles, mola mola-like fish have actually been around for 100 million years while sea turtles have been around for over 200 million years.

Now, I'm just guessing here, but this is possibly because they share a food source. That food source is low quality but abundant. It also doesn't move fast. So the mola mola evolved not for speed, but for efficiency. These flippers (like the ones that turtles and mola have) don't move you fast, but they also don't use much energy.

The fecundity of sunfish might also have something to do with the variability of their prey. Jellies are notorious for being extremely abundant year and then disappearing the next. In a situation like that, you want to have the ability to rapidly increase your population and rapidly reach the age of maturity so that you can take advantage of prey population explosions.

Research Assistance from Deboki Chakravarti

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Good morning, John.  VidCon is next week, so I'm super stressed out and not really able to concentrate on anything in particular.  The nice thing, though, is that now I'm old, so I understand that this is happening and I know the solution: very weird animals!  Luckily, the internet is almost ass good at sharing weird animals as it is at sharing celebrity drama and reality destroying rage lies.  

I realized this recently while on Twitter and seeing this very good water (?~0:26).  It looks silvery because it has a thin bubble that clings to its super hydrophobic skin.  That bubble has oxygen diffusing into it and then it exhales into the bubble and inhales newly oxygenated air, thus allowing it to stay underwater for more than 15 minutes, so John, I'm gonna start, every once in a while, sharing with you a bizarre beast of some sort to ease my own mind and maybe make us all feel better about our lives on this beautiful danger ball.

So let's start out with one of my faves: the mola mola, or the ocean sunfish.  I love this fish so much!  You might recognize them from this video.  

Person: That thing is big, Jay, what is that thing?  It looks hurt!

Hank: Or this video game.  

Person: We actually found the golden turtle!  Whoaaaa!

Hank: Or from a viral Tumblr rant that I read from some philistine claiming that "this thing is so worthless it doesn't realize it shouldn't exist".  Look, you!  That's not how this works!  The various species of sunfish are successful and you know how I know that?  Because they were doing just fine before we started accidentally ripping them out of the ocean with the rest of our fish catch and throwing a bunch of indigestible trash that looks exactly like their favorite food into the ocean.  

Yeah, they eat jellyfish, which is also the favorite food of a lot of sea turtles, which made me think if there's some convergent evolution going on here because when you turn a mola mola on its side, it kinda has a very similar swimming style to a sea turtle, almost as if there's a good reason for this ridiculous shape, and yes, I recognize that they look dumb!  In Taiwan, they call them "the fish that looks like a toppled car" and the Polish name for them is basically "just a head" which, yeah, I see it, but just because it looks funny doesn't mean it's not a good fish, (?~2:05).

They are the biggest of the bony fishes and they get very, very big, up to about a thousand kilograms.  Up until recently, we actually assumed from their lack of swim bladders and their very weird fins that they were themselves a kind of plankton, that they would just go wherever the ocean currents would take them, except it turns out they can actually swim pretty fast.  In fact, the only people who have ever been hurt by sunfish were hurt when sunfish jumped out of the water and into a boat, but that's when they're relatively young.  When they're less young, they are not very fast, they're pretty slow, but because they don't need to be fast, because they're so big and they have a fecundity proportionate to their size.  

A female adult sunfish can lay up to 300, wait for it, million eggs.  For clarity, that is more than the entire world population of adult sunfish.  Sunfish are called sunfish because they sun themselves.  They lay flat on the water, either to warm themselves up so that they can go back down deep and get cold again or because they want seagulls to come and peck worms off their side.  Maybe both, maybe neither, but weirdly, baby sunfish also kinda look like suns with, you know, like a super gross eyeball inside of 'em, and they grow extremely fast.  The Monterey Bay Aquarium had a sunfish for 15 months that grew from 50lbs to almost 900lbs.  It was so big they couldn't fit it in the tank anymore, so they had to airlift it by helicopter to freedom.  

From birth to adulthood, mola mola increase in mass by more than 60 million times, and John, their skeletons look like very dangerous spaceships.

Yeah, I get it, other animals are cute and fuzzy and they look like they're smiling at you and mola mola have their big, terrified eyes locked into a bumpy head and can't fully close their mouths and have huge amounts of parasites both in and around them, but we have no idea what's going on in that big dopey headbody and I just want all of the mola mola in the world to know, I love you.  You're doing great.  Keep being lumpy and magnificient.  John, I'll see you on Tuesday.