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Welcome back to Bizarre Beasts: Season Zero, where we are remastering episodes of Bizarre Beasts that were originally created for Vlogbrothers. This episode, Hickory Horned Devils and Regal Moths! Meet the little critter with significant “brand power”.

Get the Season Zero pin set here:

The Hickory Horned Devil and Regal Moth pins were designed by Sam Schultz. You can find out more about them and their work here:

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Good morning John Welcome back to Bizarre

Beasts: Season Zero. Hank and I are trading off hosting duties on  our year-long journey to remaster the original   Bizarre Beasts episodes from V logbrothers  with corrections, updates, and new facts. Make sure you stick around  for the pin set announcement! You know how caterpillars become  butterflies- well that is a lie.

Any given caterpillar you spot honking its way  down the sidewalk, there’s a 90% chance that that   fresh little wiggler is incapable of becoming  a butterfly and instead it will become a moth. And John, moths: oh my God they’re so good. [♪Intro♪] “What precisely is a moth?” you ask. Well here’s where it gets a little bit messed  up because butterflies are like a thing- they're like they have a single common ancestor.

Moths are just anything that’s not a butterfly: any scale winged thing that  isn’t a butterfly- moth. Is it more closely related to some  butterflies than it is to some moths? Doesn’t matter- moth! and talk  about a branding problem right, "butterfly" is this beautiful word-  it spoonerises to "flutter by." And then moth- it sounds like the noise  you make when a moth flies into your mouth but moths, moths, moths, moths, moths.

We’re stuck with the name. Let’s just look at these beautiful creatures. And the one I want to talk to you  about today is mostly the regal moth.

Why: because of its caterpillar- The  Hickory Horned Devil- which looks like this. And, bonus fact: this chonky green  look is actually the fifth instar,   or developmental stage, of  this caterpillar’s life. The earlier instars tend to be mostly black,   with the later instars being  more orange-ish or brownish. At these stages, the young caterpillars  are spinier, and the spines on their   backs branch more than the spines on  the final hickory horned devil instar.

You will never forget this caterpillar   or probably its name ‘cause it has  got brand power- brand too strong. Now there are other Horned Devils out there. This is the largest of The Horned  Devils, it’s from South America.

But The Hickory with its blue body and  its red horns-why does it look this way? Well because it’s basically a hot  dog with legs- it’s very good eating. It looks fierce but it’s not; it can’t  sting, it can’t bite, it’s not venomous,   it’s not poisonous but it’s too big to hide  from raccoons and possums so its got to make   those fuzzy folk worry about their noseys and  toesies before grabbing on and taking a bite But lots of caterpillars don’t  become gigantic food bags.

In fact, the Hickory Horned Devil is  the largest Caterpillar in the US. So why is it so big? Because the Hickory Horned Devil has to consume  massive amounts of food because Saturniid moths,   which this is one of is over 1000 species of these  guys, do not have mouths once they become moths.

Once a Saturniid Caterpillar  pupates, it will never eat again. And so these caterpillars eat 2 to 3 times their own body weight in leaves everyday,   growing in size over 1000 times in the course of a month. They don’t even digest the  cellulose of these plants,   instead they basically juice  the leaves in their guts.

Just wanted to pause here and say we  couldn’t confirm the size change or the   leaf-juicing thing when the show’s fact  checker went back through this script. If you know where those facts came from,  please let us know in the comments! Time for another bonus fact: earlier,  we showed footage of a pupa that looked   like a big brown nut, but the footage  didn’t show where that pupa came from.

Now, you might be familiar with the  strangely beautiful chrysalises of   butterflies or the silky cocoons spun  by many moths around their pupae,   but hickory horned devils do  things a little differently. Instead of attaching themselves to  a twig or a leaf, these caterpillars   burrow into ground to pupate naked,  rather than spinning a cocoon. When males emerge from their chrysalis,  they fly sometimes for miles,   trying to sniff out a female with their  extremely sensitive, feathery antennae.

Their job is to locate the  female because the female’s   job is to use all of its energy  creating hundreds of very large eggs. The female Regal Moth does not fly  until it mates and if it does not mate,   it never flies- it just dies waiting. They have to mate and lay their eggs within the  7 days they have to live in their adult forms.

So, this is another spot where we  couldn’t find the source that Hank   used for the last two lines when  he originally made this video. What we did find was a reference that said that female Regal Moths have “genuine difficulty   even getting airborne,” probably  due to the weight of their eggs. So, it’s possible that they  can fly, if not well or far.

They may also live for more than 7 days as adults,   maybe even up to two weeks, but most  references just say “about a week.” The strategy of Regal Moths and other  Saturniidae is that the moth phase exists   only for meeting and breeding and to pull that  off, the Caterpillar needs to be successful   in storing fats and proteins before it  pupates and so it has to get big and   full of nutrients which makes it a perfect  snack so it has to look ridiculously fierce. Pretty much anything would see this juicy boy  and think “that is not worth the risk” which   is also how most people feel about them  even though they are completely harmless. Still be nice because they are a marvel  even if they are a little terrifying.

If you missed this critter the first time  around, our Season Zero pin sets are now available! This set includes all 12 of the animals we began this Bizarre Beasts journey with on   Vlogbrothers, including the Hickory  Horned Devil and the Regal Moth pins! The new versions are very glittery!

To get the Season Zero Pin set,  visit! If you enjoy learning on YouTube, why not get credit for it? With Study Hall, you can take college courses that start on YouTube for only $25 Here's how it works:

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