Take a moment to think about the appearance of a modern bird – like a parrot, or something
similar. We know these animals have relatively thick bodies, feathery coats, unique patterns,
and varying colors. Now, let’s look at a parrot’s skeleton. You’ll notice that based
on the bones alone, these birds seem like they’d have long, slender frames — yet the
layers of skin and feather coverings make them look quite different than their gaunt
skeletal structures might suggest. And this exact phenomenon presents a practical challenge when it
comes to reconstructing accurate depictions of dinosaurs. An increasing number of soft tissue
discoveries have suggested that many (though not all) species of dinosaurs possessed more feathers,
layers of fat, and other unusual details than one might assume based on the outdated depictions many
of us grew up with. The challenge of capturing the forgotten peculiarities of dinosaurs is at
the center of “All Yesterdays,” a book written and illustrated in part by C.M. Koseman — whose work
you may recognize from his other most famous book “All Tomorrows.” The 2012 speculative paleo-art
book All Yesterdays was created not just by Kosemen, however, but also Darren Naish — an
expert paleontologist and author, and John Conway: a skilled paleo-artist. These three are brilliant,
and I have links to where you can follow and support them in this video’s description.
Not long ago, I covered a section of this book titled “All Todays,” in which the authors imagine
what might happen if, millions of years into the future, clueless alien scientists tried
to create depictions of long extinct organisms based solely on the fossil record — with pretty
hilarious results. But I can’t emphasize enough that, despite misconceptions to the contrary,
All Yesterdays isn’t trying to belittle the field of paleontology with these images — or suggest
modern scientists are similarly clueless when it comes to reconstructing dinosaurs.
Paleoart has come a long way, thanks in part to the efforts of these creators. The three
authors — all of whom are deeply involved in the paleontology community themselves — make
it clear that modern paleontologists aren’t just blindly interpreting fossils — but also
making great strides in integrating studies of feather impressions and soft tissue preservation
to gain complete pictures of what these incredible creatures might have looked like. However,
there are still, of course, a diversity of fascinating unknowns when it comes to dinosaurs,
and All Yesterdays explores how speculation — as long as it’s cautiously grounded in
science — can both help and even play a vital role in showcasing the intriguing possibilities
of how dinosaurs might have looked and behaved. All Yesterdays stresses a balance between caution
and speculation, always pointing out that many of the reconstructions within the pages
might be completely off the mark. That’s just the nature of speculation. With that said,
let’s get started, and imagine what unique aspects of dinosaurs may not show up in the fossil record.
The first out-of-the-norm reconstruction of a dinosaur All Yesterdays explores is of a
Carnotaurus, drawn at a unique angle by John Conway. While the bull-horned predators are
usually depicted from the side, here, the authors depict the animal head on — drawing attention to
just how strange the animal looks — with its arms stuck out to the sides in a bizarre display. The
idea behind the strange spectacle comes from the animal’s skeleton, which shows the animal had
stunted, ineffectual arms — yet possessed unique shoulders which would have allowed the animals to
spread these arms out sideways in a way utterly dissimilar to other large predatory dinosaurs,
and seemed to serve no practical purpose. So, the authors imagine the arms on Carnotaurus (and
the related Majungasaurus, pictured here in C.M. Koseman’s one of a kind style) were waved about
in mating or territorial displays, potentially alongside bright colors — not unlike many birds
today. A bizarre concept to be sure, but not altogether improbable given the available
paleontological data. Of course, dinosaur colors might have also gone in the opposite direction.
Can you see the Majungasaurs in this image? How about now? Here, the authors explore the
possibility that some dinosaurs might have had appearances which supported camouflage
and mimicry: bending into the natural features of the environment much like a modern stick-bug. Now,
it’s usually smaller animals, not predators like Majungasaurs, which employ camouflage. But some
large modern predators’ body patterns, like the tiger’s distinctive stripes which allow them to
blend into tall grasses, do help them ambush prey. So, it’s possible certain dinosaurs might have had
similar camouflaged appearances. Here’s another recreation which, at first, might be difficult to
see. This is All Yesterday’s speculative concept for a Plesiosauria, portraying the animal with
impressive camouflage. Strange though this might seem to anyone familiar with traditional portrays
of Plesiosauria, the modern oceans are swarming with remarkable forms of mimicry. Just look at the
incredible appearance of something like a leafy seadragon, and you’ll start to understand just how
incredible past ocean life might have looked. Now, the authors aren’t actually making a scientific
assertion that this was what all Plesiosauria (which for the record, weren’t actually dinosaurs,
but adjacent marine reptiles) looked like. Most Plesiosauria likely had smooth skin
for better hydrodynamics, but it’s not impossible some branches tried an ambush approach which may
have favored better camouflage. An interesting possibility for sure. Back on land, here’s a
quite heavily feathered speculative reinvention of a Therizinosaurus. The Therizinosaurus looks
quite menacing based on its skeleton alone, thanks to the animal’s absurdly long claws,
which in the past excited artists and caused them to make an overly-deadly looking animal — despite
the fact the animal wasn’t a predator. The thick layer of feathers certainly makes the animal look
less frightening, and quite different from their skeletal appearance. If you compare the
gaunt skeleton of say, an owl, however, to the quite different shape of the actual bird, you
could start to see how such a difference between skeleton and body size isn’t too crazy a concept.
Therizinosaurus skeletons also have wide hips, so it’s been theorized they have sizeable physiques.
Beyond proto-feathers, All Yesterdays also explores the hypothetical that some dinosaurs,
like Heterodontosaurus, might have had defensive, quill like structures — not unlike the defense of
the modern porcupine. Seem hard to believe? Well, a recent exceptionally well-preserved
specimen of the early ceratopsian Psittacosaurus was found with bristle-like quills on its tail.
The Psittacosaurus is actually one of the most completely reconstructed dinosaurs, and its
appearance is certainly not tame. Paleontologists don’t think the bristles on its tail were for
self-defense, but it’s certainly possible some geneses like Heterodontosaurus — which we also
now know had some kind of spike-like dermal quills — could have used their bristles for self-defense.
Going further into hypothetical territory regarding proto-feathers, the authors imagine
a group of Leaellynasaura Amicagraphica as rotund furballs quite different from the popular notion
of a ‘dinosaur.’ Far from fanciful speculation, however, the authors’ recreation is based on
evidence that the Leaellynasaura lived in a near-polar region, and almost certainly had
to endure sub-zero temperatures. While one might look at such a reconstruction and think it looks
too adorable for a dinosaur, The Authors point out the hesitancy around depicting dinosaurs as
‘cute’ is a potentially an overly-limiting one. Also incorporated into this design,
Leaellynasaura tails were almost three times as long as their body, for reasons paleontologists
aren’t quite certain of. All Yesterdays depicts their tails as strange, flagpole-like tools
for social displays. While easy to dismiss this concept as overly-speculative, the authors point
out that while it’s certainly unlikely, it’s only so much weirder than what you might see anywhere
else in nature. But appearance is only one half of the speculative puzzle when it comes to dinosaurs.
The authors observe that various unique behaviors likely weren’t preserved in the fossil record.
Just think about the mating dances of birds of paradise, the unique calls of whales,
or even something as simple as the dung rolling of Dung Beetles. All of these behaviors are huge
parts of what gives these animals their identity, and yet most of them could never be understood
from remains alone. And it stands to reason some dinosaurs might have had behaviors which
fall into the same category. Here’s an intriguing speculative example of the Elasmosaurus, marine
reptiles which aren’t actually dinosaurs, behaving in a highly unusual manner. Here, the authors
invent a scenario where the Elasmosaurus lunge out of the depths and wave their necks — competing
to prove who is the strongest. Older art of Elasmosaurus sometimes shows them holding their
necks above the water’s surface with ease, but modern paleontology has proven these animals had
heavy bones and dense necks, which could only be lifted out of the water with significant effort.
So, the authors imagine these animals exerting such strain as a form of social competition.
Of course, this is absolutely and unapologetically speculative, yet equivalently remarkable behavior
is likely lost somewhere in our past. In a similar vein of speculative thought, here the authors
imagine Protoceratops engaging in a behavior there’s no direct evidence for in the slightest.
And yet, certain breeds of goats also climb trees, a strange-looking behavior you wouldn’t
guess the hooved mammals would engage in based on its body plan alone. It’s something like this sort
of unexpected conduct which might be absent in the fossil record. (and yes, these modern goats? They
are not a hoax—they truly hang out in trees.) On the subject of dinosaurs doing things they’re not
known for, playing is certainly a significant example. Instead of showing a dinosaur striking
a pose or getting attacked by a predator, this recreation shows a Carmarasaurus grandis enjoying
a simple roll in the mud. Speculative though this might seem, almost all living animals engage in
some form of play —both larger mammals, but also various species of birds, reptiles, and even fish
take part in behavior for no other practical reason that it seems to be fun. So dinosaurs,
even if they’re sometimes thought of creatures that lived in constant battle with each other,
almost certainly engaged in play too. And here at the end is an image which, despite its simplicity,
is one of the hardest to process. It’s showing a t-rex just sleeping — but so much of our classic
perception of the creature is of a roaring monster with its jaws agape ready to strike,
that we forget the tyrannosaurus is also… just an animal. And animals sleep — especially
hunting animals, who need to conserve energy and therefore spend a considerable amount of time
resting. It’s not certain if T rex’s slept on their sides or not — but it’s still an
intriguing image that gets the viewer to think of the animal as more than just a machine of death.
Ultimately, science and speculation aren’t concepts in opposition to each other.
All paleontological art of long-extinct creatures is speculative to some degree, and thinking about
interesting — albeit unusual — possibilities, can help us appreciate all we know — and don’t
know — about these remarkable animals from the distant past. And that’s the end of our glimpse
at the intriguing “All Yesterdays.” If you liked this content, please consider supporting Kosemen,
Naish, and Conway’s work by purchasing a copy of the book — and by patronizing
their other works and social media, which as always you can find in the links below. Also,
thanks for watching. If you enjoyed this entry, please lend your support and like, subscribe,
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