Episode 110 – Ocean Sunfish: The Saucy Saucer

“And today we’re talking about fish head fish heads rolly polly fish heads. But more on that later…”

If you’re cruising around in temperate waters on a sunny day, don’t be surprised if you see a huge flat disk floating on the surface nearby. The Mola mola is a massive fish that sometimes needs a vacation to the surface to catch some rays. Not sting rays, of course, sun…rays. But why would a fish need sunshine? And why does this fish look like weird disembodied swimming head? It’s all part of the natural master plan here in Life Death and Taxonomy.


The sun fish is extremely odd looking and difficult to explain but i’ll try.

  • Take a fish head (only the head), slap on a short long, rounded caudal fin called a clauvus, stick on very long dorsal and anal fins, and then tell it something shocking.
  • You have a mola mola.
  • The fish is so oddly shaped that it can be mistaken for a sea turtle swimming sideways.
  • They come in silver, grey, white, and mottled patterns.
  • You might find these fish in temperate or tropical waters in the atlantic and pacific.

Measure Up

Welcome to the beloved Measure Up segment. The official listener’s favorite part of the show! The part of the show when we present the animal’s size and dimension in relatable terms through a quiz that’s fun for the whole family. It’s also the part of the show that’s introduced by you when you send in audio of yourself saying, singing, or chittering the words measure up into ldtaxonomy at gmail dot com. We don’t have a new measure up intro this week! That means we get to hear from an animal, and Carlos has to guess what it is. Hercules Beetle 

  1. A rhinoceros beetle
  2. A hummingbird
  3. A crow
  4. A playing card in a bicycle spoke


  • They can grow to 2.5 m (8.2 ft) from fin-to-fin.
  • How many sunfish go into the diameter of the smallest known sun (or star)?
  • Hint: The smallest star is a red dwarf called OGLE-TR-122b. It lives in a binary stellar system. 
  • Answer: 133,633,580 fish. The sun is 334,000 km (207,537 miles) in diameter. 


  • Older adults can weigh 247 to 1,000 kg (545 to 2,205 lb)
  • 2,000 lbs
  • How many Sunfish can you stack on a Toyota Tundra’s tailgate before the support cables snap?
  • Hint: Like most trucks, the tailgate is supported by two stainless wire ropes. The tensile strength of these cables are far greater than the safe working capacity of the tailgate. Meaning, other things will break, like the hinges or where the cable is connected, before the cable snaps. 
  • A little more than two fish. The breaking strength of the cables are 4200 lbs.

Fast Facts

  • Baby sunfish look like suns. Or at least child drawing depictions of the son. 
    • They have circle bodies with triangle fins going off in every direction from the radius.
  • Sunfish grow incredibly quickly and a lot. 
    • They are the largest bony fish species, to find bigger fish you have to turn to chondrichthyes, which are sharks.
    • They apparently grow the most of any vertebrate, up to 60 million times their hatchling size.
    • One Mola Mola at the Monterey Bay Aquarium grew 373 kg (822 lbs) in 15 months.
  • They like to eat jellyfish, like sea turtles, which puts them at risk of eating plastic bags, like sea turtles.
    • But they are considered generalists, which means they eat a wide variety of fish, squid, and crustaceans.
  • It was once theorized that they were poor swimmers and just drifted with currents.
    • But young sunfish are quick swimmers despite their bizarre body shape and fins. 
    • Larger sunfish are slower but they can still get around. 
  • They can live up to ten years in captivity.
    • The size of adults makes them.
  • People used to think they were plankton since they seemed too slow to move on their own.
  • Japanese shoguns accepted Mola Molas as payment for taxes in the 17th century

Major Fact: Sunburned Fish

  • Ocean sunfish are probably called sunfish for one of two reasons
    • Their babies (fries) look like little ten pointed suns with giant eyeballs
    • Or the fact that they regularly sunbathe on the surface by just lying sideways and floating around
  • You don’t usually see fish just lying on their side floating on the surface unless they’re dead, so why does the mola mola do it?
  • There are a couple of theories:
    • It likes to dive up to 2,000 feet below the surface, which can get pretty cold
      • If it stays in water colder than 54 degrees for too long, it could die
      • Sunning itself warms it up, allowing it to dive back down to colder waters
    • Because it doesn’t have scales and instead has skin covered in mucous, its huge body is home to 40 different types of parasites – mostly different types of worms that attach themselves to the outside and even the inside of its body (since it can’t close its mouth all the way)
      • To get rid of the parasites, the mola sometimes jumps out of the water to dislodge anything that’s attached to it. They’ve actually injured people by accidentally jumping into a boat
      • They also have half-moon and angel fish swim up and eat parasites off of them
      • But for the really tough parasites, they allow birds on the surface to pick at them while they sunbathe. Since they’re so big, they don’t have much to worry about when it comes to birds.
      • Plus, drying out and UV radiation sometimes kills off parasites
      • One of the most common parasites is the shark tapeworm, which only reproduces in sharks. It lodges inside the slow-moving mola mola in the hopes that a shark will eat the fish and it can reproduce
  • But lying flat on the surface has its downsides.
    • For one, the mola mola can get sunburned since it doesn’t have scales
    • And also, the birds sometimes decide to peck out the fish’s eye

It’s the end of season 11! Thank you to everyone who has helped us make this show the best that it can be. 

  • Thank you to everyone who sent in measure up intros
  • Thank you to The Honey Badgerer for leaving an awesome review for us on Apple podcasts!
  • Thank you to Brian for creating the amazing art for each episode and to Johanna for our sweet new cover art.
  • Thank you to my wife, Bibby, who has allowed me to spend part of every week working on this podcast.
  • And finally, thank you to everyone who listens to the show. Knowing you’re out there waiting on the next installment of animal facts is what keeps us going every week. Your continued support is truly appreciated.

So that’s it for season 11, but that just means a new set of 10 animals is right around the corner. Thanks for listening and we’ll see you next week with more interesting animal info!