Critter of the Week: Scutellosaurus

Meet Skittles.  She might be all hard and pebbly on the outside, but on the inside she wants nothing more than a nice warm hug.  Scratch just a little in between those rocky scutes, and she’ll roll on her back so you can rub her smooth, soft belly scales.


Skittles is happy to see you!  She wonders if you would please, pretty please, give her a treat.  Can you resist those puppy-dog eyes?

She may be about the size of a golden retriever, but believe it or not, Skittles here is the great-great-great-great-grandmother of Stegosaurus!

It’s hard to imagine how long a time span the Jurassic period covers, but we can get a few hints when we see that a little critter like this had enough time to change and diversify into animals like the spike-tailed Stegosaurus, or the armored, club-tailed Ankylosaurus.

The Jurassic period started at the end of the Triassic period (big extinction event there, to separate the two), and lasted 56.3 million years until the beginning of the Cretaceous.

56.3 million years.  Think about that.  Humans have been around for about 2 million.  Between us and the latest dinosaurs like T-rex?  About 65 million years.

So that means Dinosaurs had their “golden age” in the Jurassic for almost as long as the nearest T-rex is to us.  Pretty mindboggling.

And that’s not even thinking about the Triassic and Cretaceous periods yet…

Dinosaurs have been around for a looong time (especially if you count birds living today!).

Skittles is just happy to have a few moments to cuddle. 🙂  Completely oblivious to how long dinosaurs have been around.  Or that she’s related to Steggy. 😛

Making progress… Continue reading

Critter of the Week: Juramaia

Meet Maya.  She’s a sweet little fuzzball who loves nothing more than to curl up in your pocket.  At least during the day.  When the sun goes down, that’s when the party starts!

Maya update

Wait a second…what’s a squirrel doing in a dinosaur book?  Well I’m glad you asked.  So far, her kind is the first mammal discovered that nourishes her babies in utero with a placenta.  A placental mammal.  This is unique from marsupials like kangaroos, or egg laying monotremes like platypus.  🙂

My little girl keeps calling Maya a squirrel (she’s 2 🙂 ), but she’s a bit more like a tree shrew.  Little Maya has sharp little teeth that are great for just about anything she can get her paws on, but bugs are her favorite.  That slender nose helps her sniff them out in the dark.  She has long arms and sharp claws that make her completely at home in the tree tops.

When you’re the size of a squirrel it’s good to be out of reach of giant dinosaurs!

If you want to learn more, here’s a great news article with a picture of the beautiful fossil. It even has fur!

Making progress… Continue reading

Critter of the Week: Pterodactylus

Meet Terry. She’s a chipper little flyer who would love to scramble up onto your shoulder and nibble your ear (just a little nibble, it tickles).  And could she please, pretty please have a tiny bit of that sandwich?


Terry always likes a snack, especially small morsels like snails, grubs, and worms she digs up.  That sandwich looks quite tempting though, and she won’t turn her nose up at an opportunity to snatch it out of your hand, so keep an eye and a firm hold on it. 😀

She might not look it, but this little pterosaur (not dinosaur), is very good at walking and running around on the ground.  She spends a lot of her time poking her sensitive snout in the dirt for all sorts of burrowing creepy crawlies.  When she feels one, she nabs it with her tiny teeth and gulps it down.  Yum! Continue reading

Critter of the Week Dilophosaurus

Meet Picasso.  This quiet softie loves spending time with his special person.  Snuggling under the tree to hear a good story?  That sounds like a lovely way to spend a warm afternoon. 🙂


Picasso looks very happy to see you, and he wonders very much if you like his red crest.  He’s very proud of it, you see, and he’s been strutting around the field like a very large rooster.

He marches up and down the fence line with his chest puffed out and his neck arched like a stallion.  He watches over his patch of yard like the duke of the land, and if something doesn’t look quite right, he’ll stand as tall as he can and show off those blue feathers- just so you know he has things under control.

Oh yes, feathers!  Now we don’t know for sure if this critter had feathers or not, and the whole subject of feathered dinos deserves it’s own series of posts, but there’s a definite possibility. 🙂

If you want to find out more about dinosaurs and feathers, here’s a post on what makes a feather, and here’s a post on figuring out which dinos might’ve had them. 🙂

I’ve given Picasso a coat of feathers similar in texture to an emu’s, which gives him the furry look.  His fingers and feet are feathered too, like a snowy owl, but they have pads on them for walking and grabbing.

If you’ve watched a lot of Jurassic Park, take note that Picasso has awesome grabby hands that are good for hugs.  Not dangly zombie bunny arms.  What good are those for? 😛


Making progress…


Happy New Year!  I hope you’ve been having a good holiday season.

I have big plans for the new year…Here’s a basic list, kinda in the order I want to accomplish it.

  • officially set up Mailchimp so that I can launch Pete’s Postcards from the Shop.
  • Finish Dippy vs. Ball so I can publish my first book (ever.)
  • Earn my first 99 cents from said book. 😀
  • Prep Dippy vs. Ball to make a print version available.
  • Create more Critter Cam episodes until I have enough for the anthology, which will also be available in print.


  • Publish “Little, Quiet Dinosaur” (working title) by my birthday this year!  We’ll see how realistic a goal that is later, but I’ll try my best to have it at least finished (if not ready to publish on Amazon).

I have a strategy in mind, to make sure this happens.  Once Dippy vs. Ball is published, I’ll then work on an illustration for the picture book.

With an illustration complete, I’ll prep Dippy vs. Ball so that it can be available in print as well.

Then another illustration for the picture book…then I’ll start a second Critter Cam episode…you get the picture. 🙂

This way I hope to have more books out there (and therefore more easily seen, so future readers know I exist) while still making progress on the picture book. 🙂

P.S. – In case you didn’t notice, Picasso got an update!  

  • He looks more like most of the other critters now, style-wise
  • He’s more balanced over his hips now, and doesn’t look like he’s about to fall on his face
  • His head crest is shorter, and more like the latest skeletal drawings
  • His body is leaner, since I gave his feathers a slightly shorter, more fur like look.

Here’s the older picture for comparison. 🙂


Coming Next Week…

This big guy is always ready to flash a big, toothy smile, especially at mealtime.

Share your guess in the comments! He’ll be one of the critters over on the critter page. 🙂

The Art and Science of Alfred

Hello there!  Alfred is super excited to see you, and look at how curious he is.  Do you own a cat or dog?  Because he seems to think you smell good. (stay back Alfred, be nice).  Here we go, I’ve got a nice ball of cheese and bacon here.  He’ll love it.  Here Alfred, go get it!




While Alfred gets the ball, I can share this lovely disclaimer.  Que elevator music…

I do the best I can with research, but I definitely don’t claim to be an expert.  I try my best to keep up to date, and all my illustrations reflect this. (thank you internets, and to all hard-working paleo-nerds who are kind enough to make your papers open source!) 😀

That said, all the drawings in the A&S post series are quick doodles to illustrate a point, with not as much reference as I usually use, so there are plenty of inaccuracies for you to point out for me. 😉

Thank you disclaimer, you can go bother someone else now. 😛 Elevator music fades out…Oh and here comes Alfred!  Looks like he wants more…


There we go, good boy Alfred!

Now Alfred here is an Allosaurus.  He’s young, so only about 12 feet long so far, but he’ll grow to be a lot bigger.  Not as big as his wild cousins though, a few of them could be as big as T-rex! (very few, gotta be old to get that big, and most dinos have a live fast, die young policy)


1. On Scaly Skin vs. Feathers

So you see Alfred here has these lovely bright yellow and forest green scales, the colors of youth. (They’ll mellow out a bit when he gets older, like monitor lizards do)

Also like a monitor lizard, you’ll notice that most of Alfred’s scales are quite small, with a rather pebbly texture.  They get a bit larger and thicker on his back, which is good since adult Allosaurus tend to get into quite a lot of tussles with each other.  But most of his scales have that nice cobblestone look to them.

Like this guy, remember him from last week’s post on feathers and scales?


Short answer as to why Alfred has scales…there’s a young Allosaurus with preserved scales somewhere on it’s body.  (Unfortunately the report didn’t say where)

Long answer was so long I made a post out of it…To Feather or Not to Feather Your Dinosaur, That is the Question.  (The komodo dragon above was laying around in that post.  So was this gal, she’s a monitor lizard. 🙂 )



2. Getting Comfy…

*happy sigh* Oh look…nom? -Alfred

Looks like Alfred’s all worn out from chasing after that giant, cheesy bacon-ball.  He hasn’t quite grown into his adult silhouette yet.  He’s still young enough to think he can chase after stuff, but he’s starting to get to an age where it’s getting hard to make those quick turns.

When he fills out his more barrel-chested adult figure, he’ll be spending quite a bit of his leisure hours (think energy-efficient) laying around.  Since his body is a bit taller than it’s wide (more lanky cat than double-wide gator), it’s more relaxing to be lounging on his side.

Of course, that doesn’t mean he can’t do other things to relax, even things that may surprise us (ever seen a large horse roll?  It’s hilarious 😀 ).

Good boy! Roll Over!


Oh, and here’s that horse… 😀 I can totally picture some “duckbill” dino doing this.


3. Where are His Teeth?!

Show us your teeth copy.jpg
Clearly I need more practice drawing people.  Thank you for volunteering Pete. 🙂


I hear ya, I wondered the same thing when I looked up pictures of Komodo Dragons and monitor lizards.  But wait, what does that have anything to do with it?

Pete will help us out here.  I know Alfred looks a little awkward, but he’s actually quite comfy.  Ah- I’ll let Pete tell you the rest…

“Thank you.  Yes, Alfred is quite at ease here.  I’m not heavy to him at all, and he weighs at least a good 300 pounds at this age.  So he doesn’t mind a bit.

I’m tilting his head back very gently- show us your teeth there Alfred, that’s it, nice and easy.

See this is the biggest difference between a domestic Allosaurus like Alfred here and a wild one.  Look how completely relaxed he is.  He’s not fighting me at all, and even his eyes are closed, look at that. (Alfred makes a gurgly, kinda purring sound in his throat)

Anyhow, I’m holding onto his lips here so I keep my fingers out of his mouth.  My fingers can look a bit like treats, so I’ll be sure to keep them right at the edge here, at the gums.

All this, the lips, the gums, the saliva- it all keeps his teeth nice and moist.  Dinosaurs have a healthy coat of enamel on their teeth, same as your teeth, and the key to healthy teeth is to keep them moist.  Even better if you can give your teeth a constant bath of saliva.

Yes, drool is essential to healthy teeth!

Now Alfred will lose his teeth and grow new ones, just like crocodiles and alligators do, but if you look closely at these teeth-they’re serrated.  They’re like steak knives- not like the cone-like teeth of crocodiles.

Thank you Alfred, you’ve been quite patient.  Here’s some jerky. 

But crocodiles don’t need serrated teeth.  They’re eating different things, they have a different habitat, and different diet, they’re eating in a completely different way.  Alfred has teeth like a bone saw.

Ever cut a roast turkey with an electric knife?  That’s what Alfred’s teeth are doing when he eats, so they need to stay sharp, and they need to be strong in his mouth.  So the gums hold his teeth, and his lips keep them nice and moist so they stay strong and don’t get brittle.”

Thank you Pete, and Alfred.  Just for comparison, here is a crocodile monitor lizard.

Looks friendly doesn’t he?  Image not my own, but I couldn’t find who to credit.  If you know who I should credit, please let me know. 🙂

My first thought, “Where are the teeth?!”  Then I noticed those sharp white triangular things inside the lip.  Also interesting is that it looks like there are pockets for the bottom teeth to slip into. 🙂  Here’s the skull of the same animal…

Image not mine.  If you know who I should credit, I’d love to give credit where credit is due.  Thank you. 🙂

They look quite different from the other picture don’t they?  Almost, shall I say, dinosauresqe?  Take a look at an Allosaurus skull. 😀

Image copyright to Jason R. Abdale.  

The one and only skull I could find that doesn’t have its teeth halfway falling out of their sockets (it happens when the dead critter decays).  Jason has many more pictures of the Allosaurus mounts at the American Museum of Natural History, and I’d highly recommend you check out his blog post.  You’ll also discover all my errors and where I need to fix Alfred. 😀

 Quick Question: Help me find what I need to fix!  If you wouldn’t mind checking out this blog post on Allosaurus, you’ll get to see some great pictures of excellent mounts, and you’ll see what I have to correct in my illustrations of Alfred.  

I’d love to hear from you in the comments!  I’ll be posting a comment on how many I find, and let’s see if we come up with the same ones or more. 😀

P.S.- You can always hop over the the A&S page to pick out who you want to see next! 🙂

Designing a Book Cover

We interrupt our regular Monday program (The Art & Science of Pete’s Paleo Petshop) to give you a bit of quick behind-the-scenes sneak peak.  I’m deep in the heart of picture-book production, and I’m at the point where I want to have the front cover all nice and shiny, so it can be the proverbial carrot at the end of the stick for me.

If I have a clear image of what I’m headed for, then it may be easier to keep heading that direction. 🙂

I would like it very much indeedy if I could have a bit of feedback.  Doesn’t have to be much, just enough to help me steer in the right direction. 🙂

First though, a quick (and brief!) rundown of what’s needed in a picture book cover.

  • Visually appealing- obvious is of course obvious.  What’s your first reaction when you see it?  A resounding yes!  Or…not quite hitting the mark?
  • Gives hints about the story- it makes you want to know what happens.
  • Gives you a “feel” of the story.  Style, general mood, if it’s funny or serious, etc…
  • Text is clear, and can be read from a distance, or at least get you to take a closer look.
  • Would you buy it if you saw it on a shelf?


There’s more to designing a book cover, but those are the basics.  So I have a couple of questions for you…

  • What’s your first reaction when you see the picture?
  • Would you pick up the book if you saw it on a library shelf?  Please tell me why or why not. 🙂
  • Are there any questions you have about the characters or the illustration?  Does it make you want to know more, or know the story behind it?


With those questions in mind then, here is the sketch.

Cover copy.jpg


And here is the colored version as I have it now.  It’s only colored as much as necessary to get an idea of style and general look.  It doesn’t have fine details yet.




Thank you for swinging by my little corner of the internet, and thank you for taking the time to chat with me today. 🙂  I think it’s pretty awesome that indie publishing is an option, and that you can be a part of this.

Here are those questions again, and it would be most helpful if you could answer the questions for each image above.  Whichever ones work best for each picture. 🙂

  • What’s your first reaction when you see the picture?
  • Would you pick up the book if you saw it on a library shelf?  Please tell me why or why not. 🙂
  • Are there any questions you have about the characters or the illustration?  Does it make you want to know more, or know the story behind it?

Thank you again for taking the time to help me give you something better. 🙂  I love to read your answers in the comments! 😀

The Art & Science: Steggy

Hello there Steggy!  She’s followed me here because she wants the bucket of tasty fern balls I’ve brought with me.  That works out nicely, since she’ll stay here and munch while we point and chat about her for a few minutes.  Just like when we talked about Ajax last week, I’ll stick with 3 research tidbits for now, to keep things short. 🙂


A&S_steggy copy


1. Soft or hard-shelled turtle?

Steggy’s a bit smaller than the average wild stegosaurus, but she’s still quite a bit taller than we are.  If you reach up on your tip-toes you might be able to touch the biggest of her plates, the one right above her hips there.

There’s been some speculation in recent years on if these plates were hard and covered in keratin- like a turtle’s shell or cow’s horn- or if the plates were soft and covered in scales or skin.

I did a bit of digging (research wise), and came across this lovely gem of information written by Darren Naish. He cites a paper provided by Christiansen & Tschopp (2010), who reported a continuous sheath-like covering on one of the plates they referred to another spiketail known as Hesperosaurus.

hesperosaurus copy.jpg
Hesperosaurus. A much smaller spiketail, but so close a cousin that there was a bit of disagreement a couple years back if it should be lumped in with Stegosaurus.

So there you have it.  Hesperosaurus is a very close cousin of Stegosaurus, so in the realm of phylogenetic bracketing that makes it more likely that Steggy had a smooth, hard sheath of horn on her plates and spikes.


2. Armed to the teeth.

tough steggy copy.jpg
One of Steggy’s wild relatives, a Stegosaurus ungulatus to be exact. We should probably back off.  He doesn’t look too happy that we’re so close.

The same Hesperosaurus described had another very rare insight on spiketails- fossil skin.  As you can see on Steggy here, most of her body is covered in small, non-overlapping scales, called tubercles.  They look a bit like pave stones don’t they?  Now look up here, a bit higher up on her side.  Interesting isn’t it?


steggy skin copy.jpg

Steggy has some pretty tough scales.  These large oval scales are called osteoderms, just like the large, hard scales on the backs of crocodiles.  They’re covered in keratin, like our fingernails, and they do a pretty good job as armor.  I’m sure Alfred‘s wild relatives had a tough time munching on wild stegosaurus. 🙂

  • Large, horn plates protect the spine
  • Bony neck armor protects neck from predators and prickly plants
  • Short front legs can bring head lower to the ground (harder to reach) and spiky end up, or push the body up to swivel on powerful hind legs.  Awesome for quick, sharp turns.  No way a hungry predator can get to anything soft and vulnerable if that spiked mace is always between it and the stego.


3. She might not be the sharpest rock, but she’s one tough cookie.


spiketails copy.jpg
Yeesh, I definitely need to practice these guys more.  Fun fact, there are track ways of stegosaurus in small family groups, with young juveniles with a few adults, or a few “teenagers” traveling together.  🙂

Steggy might have a brain the same size as a dog’s, but she’s not nearly as dumb as movies and the media would have you think.  (I’m looking at you Spike, in The Land Before Time).  I think most encounters would not have ended up like the stego in Disney’s Fantasia (which is totally what inspired my love for them in the first place 🙂 )

With all that armor, and tons of fossil evidence with some serious dino damage on Alfred‘s wild relatives, it looks to me that spiketails had an attitude to match their prickly array of spikes and plates.

Because of that, I’ve given Steggy a  bright warning pattern.  Someone told me it reminded her of a skunk, and that’s exactly what I’m going for.  Steggy’s color is something that says “stay away!”

Good thing Steggy is a calm and peaceful pet then, a domesticated spiketail.  Domestic spiketails have a tendency to be nervous, and spook easily (like horses), but Pete works with her a lot, and hardly anything bothers Steggy now. (horses can be trained like this too)

Just for fun, here’s my reasoning on why Steggy may not be as dumb as you think.  A quick check on Youtube brings up plenty of smart tortoises.  Yep, after discovering that it couldn’t fit through the pet door, this one figured out how to open a sliding glass door.


Quick Question: Animals do all sorts of crazy things we wouldn’t expect.  Do you have a story about an animal or pet that did something unexpected?  I’d love to hear your answer in the comments!  

P.S.- You can always hop over the the A&S page to pick out who you want to see next! 🙂

The Art & Science of Ajax

First up is Ajax (hi there Ajax! Give’em a smile), because really he’s the first critter of the lot I ever drew, and he shows up in my sketch book a lot.  Plus he’s just an all around friendly guy, and anyone knows a brontosaurus (ahem, Apatosaurus) when they see one. 🙂


A&S_ajax copy.jpg


So what’s science and what’s art?  To keep this post short, I’ll cover three main points (there are always more, but we can save those for later).  All drawings in these posts are quick doodles to illustrate a point, with not as much reference as I usually use, so there are plenty of inaccuracies for you to point out for me.  But I do have this great toy model replica to look at when I’m clueless as to how something looks at certain angles. 😉


apato toy.JPG
Clearly I have a lot to learn when it comes to photographing these things, but everyone starts somewhere right?  Hehe, and yes, that’s a toy.  Papo’s latest model of Apatosaurus to be exact, inspired by Sideshow Collectibles’ Apatosaurus, which is double levels of gorgeous and ten-thousand times more expensive. 😛

1. Toothy grin, or soft smile?

For starters, let’s talk about Ajax’s smile in the picture above.  There’s a lot of discussion on dinosaur lips-  did they have a toothy grin like crocs, or closed lizard-type lips?

On one hand there’s the study by Ashley Morhardt (unfortunately I can’t find it, so I’m relying on 3rd party sources).  She compared the skulls of prehistoric and modern animals, and looked at the clues left behind by beaks, lips, etc…and her study suggests that sauropods like Ajax had a face more like a crocodile’s than the fleshy lips of mammals.


This article by Duane Nash on the giant canine teeth of saber-tooth tigers (smilodon & relatives) gives some food for thought.  The blog post has all sorts of cool info of what makes a tusk vs. a tooth. 🙂

Ajax’s teeth, like most dinosaur teeth, have a pretty healthy coating of enamel, the same stuff that coats our teeth and makes them hard.  Enamel does best when it’s bathed in saliva 24/7, which is why mostly all animals that have enamel-rich teeth have mouths sealed shut by lips of some sort.

Anyway, Ajax eats whatever he can get a hold of.  He does replace his teeth every once and a while (unlike our permanent set of adult teeth), but still, it takes a while to get a replacement tooth, so he needs to use each set for as long as he can.

With that in mind, I’ve decided to reconstruct Ajax and the other sauropods with closed, lizard-like lips.

It’s one of those things that we can’t know for sure, because even a mummy can’t give you a perfect picture, anymore than a raisin can tell you what a grape looks like.


2. How far can he stretch?

Bronty herd sketch_flat

Oh boy, paleontologists have gone back and forth on this one for over a century.  First thin, graceful necks like swans, then BBC’s Walking With Dinosaurs comes out and shows the fruit of research claiming that Ajax & Dippy held their necks out like suspension bridges.  They held their heads and tails in almost a straight line, and were unable to lift their heads higher than their shoulders.


ajax neck flex.jpg
He’s really trying to impress you

More recent work has pointed out that if you add space for cartilage between the bones, then the necks of many sauropods had the flexibility to loop in a complete circle.  The brilliant minds behind the SV-POW! team over at (always enjoyable to read, but definitely more on the technical side) helped rekindle my love for the long-necked giants by holding their heads high again, and regain neck flexibility by taking soft tissues into account.


neutral ajax copy
Ajax noticed something interesting

My latest research just today, I come across a paper studying ostrich necks, and what that means for how far Ajax can stretch.

In short, we don’t really know.  But Ajax would probably have a great deal more flexibility than Walking With Dinosaurs would have you believe.  The bendiest part would be the middle of Ajax’s neck, with the ends less flexible.

I always think that animals are more capable than we usually think, so one of Ajax’s buddies has reached back to scratch at an itch on his leg. 🙂

Oh, and those two in the back with the puffy necks…that’s entirely speculative.  Something weird was going on with Ajax’s neck though, that’s for sure. 😉


3. I think we need some bigger horseshoes…

feeding Ajaz sketch copy
Pete bringing Ajax a bucket of fern spores, yum!

Feet, especially the front feet, are usually drawn very, very wrong when it comes Ajax and his relatives.  Many artists will slap elephant feet on them and call it a day.  But take a look at one of Ajax’s tracks…


Ajax tracks copy.jpgAjax’s legs are like solid pillers, and all the finger bones are wrapped together to form a fleshy, padded, hoof-like structure.  Only the “thumb” has a claw, which has some limited mobility depending on the species.  Ajax can move his thumb claw up and down a little bit. 🙂

Scientists disagree on how much Ajax could move his wrist.  So how far he has his front foot bent at the wrist is a bit speculative.

I’ve done a terrible thing and made his wrist flexible based on an elephant’s range of movement. 😛


Quick Question: Is there anything in the popular media you can think of about Ajax and other sauropods?  What common misconceptions do movies like Jurassic Park and The Land Before Time give about Ajax and his cousins? 🙂  I’d love to hear your answer in the comments!  

P.S.- You can always hop over the the A&S page to pick out who you want to see next! 🙂