drip | david’s really interesting pages…

Cephalopod Love

Here’s some wicked, eight-legged love with a great message, all wrapped up in a fantastic animation. Enjoy, and pass it along (but only if the signs say so).

Dr. Sidor’s Triceratops – crowdfunding

Add crowd-funding to the many ways to participate in science, thanks to Microryza. Am curious what the scientists think about this venture, which is basically kickstarter for science funding. I’m a bit skeptical if the public will fund things that they don’t understand, but I think this could be interesting as a model for outreach projects. And for filling holes in projects like… excavating a Triceratops? Adopt a dinosaur, like you can adopt zoo animals?

Via gizmag.

walk, don’t run…

biomech_elephant-walk

and here the same walk at 1/4 regular speed:
biomech_elephant-walk-4

Updated work on the study Biomechanics of locomotion in Asian elephants by Genin, Willems, Cavagna, Lair & Heglund. I’m getting a better grip on the staggered footfall patterns and the forces which are driving them forward, visible in body lunges particularly in the treadmill versions.

Another paper of direct relevance is The movements of limb segments and joints during locomotion in African and Asian elephants by Ren, Butler, Miller, Paxton, Schwerda, Fischer and Hutchinson. That has much more detail on each individual joint.

Mike Keesey speaks dinosaurish

Mike Keesey posted (facebook) this very cool people-speak translation as an experiment in communicating specific ideas “to laypeople without using words like Aviremiges and Ornithothoraces”.

Triceratops is a stem-bird but not a birdfoot. Carnotaurus is a birdfoot but not a birdfeather. Compsognathus is a birdfeather but not a birdwing. Velociraptor is a birdwing but not a birdflier. Confuciusornis is a birdflier but not a birdbody. Enantiornis is a birdbody but not a birdtail. Ichthyornis is a birdtail but not (quite) a bird.

Pete Buchholz chimed in:

The new birds are split into the beyond birds and the crown birds. The beyond birds are made up of dove forms and swift forms. Flamingos and grebes are admirable birds and are within the pigeon forms. The crown birds are made up of the-big-pelican-group and a clade of plover shapes and the-big-sparrow-group…..​..

shadows

Terminology isn’t as conform as could be, so here a quick overview.

shadows11

All of these images are lit with one distant light. The first is out-of-the-box black shadows. The second has ambient activated, with fills in light everywhere, like having a layer of white overlaying your image, pulling up the blacks but leaving the white as is. Note that these both cause very flat shadows, even on the cylindrical form of the legs, so that the volume is lost.
The bottom image is still one distant light, but now the light is bouncing one time off of the floor, off of the dinosaur itself, filling in those shadows. Way overexposed, because there’s a lot more light in the scene. Twice as much, to be exact, because the rays aren’t dying right away when the hit a surface, they’re bouncing off until they hit the second surface. Then they die. Note the gradation in the shadow and the way that the shadow bunches up in areas where surfaces are close up to each other. This is occlusion. Light doesn’t make it into nooks and cranny as often as it does onto wide open surfaces.

shadows2

Here I’ve changed the color of my surface to grey and dropped the diffuse value to 80% to get more range in those values. Global illumination techniques often require very different surface shading. As you can see in the lower two images, the background – the only thing that’s been altered – also affect the lighting. Indeed, all light sources have a prominent effect, luminous surfaces as well as lights. And the more specular/reflection an item has, the more light intensity will be passed on.

Skeletal Reconstructions; discussion

Scott Hartman has launched a valuable discussion about skeletal reconstructions, to which this post is more or less an illustrated comment. So – if you haven’t already – you should check out his blog, and particularly the last posts about skeletal poses, reposes and style (parts one and two).

skel01

First off, there’s the discussion of what might be a standardized pose to replace the one claimed by Greg Paul. Above I’ve taken Scott’s Majungasaurus  and fit him to the implausible running pose. (Sorry Scott.) Everyone agrees that that’s not good. But if other theropods are shown in the extreme locomotion gait while  Majungasaurus alone is left to walk, that is information. namely, it communicates that Majungasaurus couldn’t run, ie. the walk gait was its extreme. I won’t get hung up on this, but assuming the goal of a skeletal reconstruction is to communicate maximum information, establishing an across-the-board walk pose seems to weaken this objective.

What IS the goal?

Scott’s posts are already leading up to this conclusion, but I’ll try to state it plainly. Skeletals should fulfill their function, and as there are numerous functions for them, there should be numerous ways of doing them. The exploded view seems ideal for those presenting an analysis of the bones themselves, while a posed reconstruction would better suit someone analysing biomechanical features. Problems occur when the presentation seemingly lays claim to information that isn’t in the model, so its great to see Scott point to this so directly. Really good stuff. It feels like those 3D skeletals on low-budget TV shows… they look like bones that have just been dug up and prettied. But they’re not at all like the bones that specialists know they should. Result: disconnection.

What is my goal?

I’ve been exploring the creation of just such 3D skeletals and have a couple of observations to contribute from the point of view of a 3D animator not all too far removed (approximately 1 1/2 years) from those clueless artists from the above-mentioned TV shows that you scientists, justifiably, criticize.

I want to create interactive, 3D skeletal/life reconstructions that are interlinked to biota profiles and phylogenetic timelines so that important concepts like deep time, evolutionary relationships and ecosystems are communicated passively, like a background tapestry while people satiate their fascination for Trex. Or Kentrosaurus.

Eye candy: here’s an Archeopteryx reconstruction as a walk-cycle animation consulted by Scott himself. It blends from stylized life-reconstruction to stylized skeletal. Or more exactly, an abstracted skeletal. I’m not trying to make something that looks like bone or stone, but rather something that conveys those features that makes these bones identifiable as belonging to Archeopteryx. I know that many viewers will find it odd, but I like the fact that it looks sculptural and not at all like bone. The look of bone is easy to achieve, and uninformed viewers immediately assume it to be bone, which lends it a superficial authority. Ah, that’s a bone! It must be the bone.

In this specific context of continuously progressing scientific results, it must be a good thing to communicate that this creature must have been so – not that it was so.

The thing is, I look at the scraps and shards that capable scientists puzzle together into what most people think is directly dug up out of the ground and I recognize next to nothing. I look at interspecies diversity and am grateful that I’m not the one determining where the line between species is to be drawn. The more I learn the more I understand how much interpretation is involved in each step along the way, from lump in the ground to a bone reconstruction, a skeletal reconstruction, a life reconstruction.

Instead of being put off by this, I find myself fascinated by it, and I want other people to be fascinated by it too. That requires an understanding of the scientific process… ie. an awareness that there are many interpretive steps involved in that visual.

sketchetal

In the Archeopteryx animation, the spine is a volume study without individual vertebrae. In this sketch (blatantly copying – once again – Scott’s lead) I’ve depicted Silesaurus as a sketch. It’s interesting to see how reactions vary and, unfortunately, I fear that it would be taken less seriously. The scientist interested in exact numeric counts of caudal vertebrae will be disappointed, of course, but to the interested layman, it otherwise conveys a large portion of the same information correctly. Just – it looks unfinished. It surrenders authority for the author’s signature, together with the implied fallibility that goes along with having been authored. Fallibility is an assumption that leads to independent confirmation of results… a key part of the scientific process?

Scott’s discussion has prompted me to more precisely wonder what style would best suit a skeletal reconstruction for popular, interactive publications.

Red Sea part 4

love filter

cucumber yum

eagle family

scaretourist

fish curtain

Red Sea part 3

big

octopus lair

eagle ray

daily lionfish

Red Sea part 2

back2school

chillin'turtle

coral bouquet

coral home

green

RedSea part1

blue clam

coral kiss

jellyfish feast

pink moray

inmate fish

Being immersed in nature can’t be compressed into pixels, yet I humbly tried to capture the experience anyway. Here (above and in the coming days) are tiny, small and large inhabitants that more or less graciously put up with my paddling about in their space.

Archie: Ninja Chicken!

Seeing is Believing – not

One of the things that fascinates me about paleo-people is the layered depths of knowledge that is or isn’t taken for granted. I fondly remember climbing into a stone quarry with Richard Leheis, less in anticipation of finding a worthy fossil myself but in taking witness in this man’s literacy. Experienced fossil hunters can read stone. I slight bump in the surface of a slate sheet, combined with a slight discoloration at a broken edge and the knowledge of context (what type of stone is this from what historical epoch) combines (for Richard) into an incredibly accurate prediction of an animal or plant positioned in a certain way beneath this slab of stone are – to my eyes – absolutely nothing.

I’m an artist/animator. I have decent anatomical knowledge (Heinrich would correctly addend – mammalian anatomical knowledge) and little or no expertise in paleontology, biomechanics, etc… working hard to fill in those gaps and clever enough to say – hey, knowing what I don’t know is my greatest advantage! And reveling in those moments where my world is turned upside down. What choice would I have, other than to be grumpy about it?

Case in point… Archaeopteryx’s toe.

archtoe

As you can see from this collage of artists as renowned and varied as Reichel, Paul, Heilmann, Frankford, Wellnhofer, Knight, Sibbick, deSeve (yeah, I even check out concept art from IceAge), mounts in Berlin and Eichsaett… more or less every reconstruction seems to show consensus concerning Archie’s toe. Namely – it’s bird-like and conducive to perching. Across the board.

What could you possibly have against that? I mean, look at the fossils:
archtoe2

There it is. Before your very eyes.

So – how does Scott Hartman come to this reconstruction?
archtoehartman

I admit to a moment of smugness, thinking I’d caught Scott in an error so very untypical of him – his work commands my utmost respect. But how could he come to such a – literally – 180 degree difference to so many giants of paleoart? Well, if there’s any moral to today’s story, it’s this – stay humble. I contacted him to ask him about this, and good thing about that – preparing my question with a one-glimpse type graphic so as to steal as little of his time as necessary, but in retrospect it would have been more professional to (as Heinrich would say) read the f*cking paper. It’s all there, but Scott was kind enough to patiently roll it out for me. His answer is

Yes, the toes are clearly not retroverted in any specimen.  Middleton first showed that dinosaurs with reversed metatarsals (which appear to only be ones further up the tree towards birds) have a distinctive twist in the first metatarsal…if you think about it, developmentally this has to be so, since you can’t just rotate a single phalanx around the axis.

Archaeopteryx clearly lacks this.  Moreover, on the Thermopolis specimen the metatarsals are preserved much better, and you can clearly see that the first toe has rolled out of proper articulation with the metatarsal in order to appear reversed (and actually, ALL the toes are disarticulated…toes 2-4 rolled the opposite direction)

Taphonomically it works like this: the three dimensional skeleton gets flattened as sediment piles up.  The large curved toe claws end up having to get twisted to one side of the other because of their shape.  The number one toe is slightly offset to the inside (probably 15 degrees give or take).  As a result it tends to flatten the opposite way of the rest of the toes.
Anyhow, I know it sounds like I’m saying “don’t believe your lying eyes” with those other specimens, but the feet are not preserved well enough to show the actual articular capsule, and it was on the Thermop specimen (and it clearly shows you can’t articulate them while retroverted).
And the corresponding section of the paper:
Toes: As detailed by Mayr et al. (2005), and also assumed by Middleton (2002), the first toe of Archaeopteryx was not fully reversed as in modern birds (contra, for example, Wellnhofer, 1993). In the new specimen, it is spread medially on both feet (Fig. 13).
Metatarsal I attaches to the medial (not medioplantar, contra Elanowski, 2002) side of the second metatarsal, in approximately its distal quarter, whereas it attaches to the plantar surface of the tarsometatarsus in modern birds with a fully reversed hallux (Middle-
ton, 2001); its proximal section even protrudes slightly further dorsad than the second metatarsal (Fig. 13). Moreover, the shaft does not exhibit the torsion characteristic for birds with a fully reversed hallux (Middleton, 2001).
lessons learned:
archtoemesh
1) My 3D reconstruction will be at least in the realm of accurate, as Scott gave me detailed visual feedback. Archaeopteryx was not a percher, was not a tree-dweller, was not a bird in the form that the word tends to conjure up. The species has just gotten a lot more interesting to me, as has the whole chapter of early avian evolution.
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2) 3D reconstructions can communicate articulation much more precisely than 2d profiles can ever hope of doing. They also have the potential of illustrating all that scientific terminology in a direct, visual and possibly interactive way. I hope that I can contribute to so that I myself will be less lazy in wading through all those words, heeding more consistently Heinrich’s advice… read the literature.
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3) Someone literate in articulation has to articulate these things. Someone who’s learned not to trust their eyes.
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Papers Terminology…

  • The tenth skeletal specimen of Archaeopteryx
    Gerald Mayr, Burkhard Pohl, Scott Hartman , D. Stefan Peters
  • taphonomy = the study of decaying organisms over time and how they become fossilized
  • medial = towards the middle, (not just having to do with media)
  • I’ll try to do up a graphic of all those other terms once I have other things out of the way

110307; phorusrhacos re-work

terrorbird2

Reworked composition, painted a bit more and played with an idea for a (hopefully) non-obtrusive watermark – based on current correspondence about the distribution models of paleoart. Very iffy on this though, and this image is far from anything I’d consider production quality.

What are your thoughts?

Attenborough does Pterosaurs

An IMAX 3D film on pterosaurs, hosted by David Attenborough! Has anyone seen the Sky 1 preview?

Kentrosaurus part 1; the research

kentrosaurus-spike

You say tomato, I say tomato – and yet we both sound completely different. Bones are bones, and yet everyone is convinced they go together in different ways, supported different tissues and were used in different ways. As an artist, it’s easy to find this frustrating. Can’t I just get the blueprints and get to work?! If Kentrosaurus looks as divergent as in the three images above, how can they claim to be scientific? I mean those are constructions by a gaming model, the Geological Museum in Warsaw and a mount in Tubingen. Err. gaming model, what’s that doing in there?

Well, the long spike is either presented as being over the shoulder or hip, and  it was the first case I found of a literal compromise; smack dab in the middle. While that’s one way of dealing with the controversy I’m going to follow a different path – I’m going to reconstruct Kentrosaurus, making all these controversial decisions myself. Fortunately, I’ll be accompanied on my journey by an authority on the subject, Heinrich Mallison.

The goal is nothing less than impressive still imagery that communicates defensive behavior posited in Heinrich’s paper.

So, where where the spikes? What posture is plausible? How can I pose this guy to communicate behavior? How do i find time to actually get the work done? All this and more hopefully before the end of the month, possibly a bit beyond.

Freestyle getting slicker

NPR; it tickles!

In the discussion round of a recent talk, Ken Perlin discussed the linguistic allure inherent in the following sentence…

Time flies like an arrow,
fruit flies like a banana.

It tingles. And lingers. You have to go back and re-read it. Or you want to hear it again. Why? The words in the second half present themselves in one way due to the repetition, then reveal themselves to be something other than what they were expected to be. A verb becomes a subject, a preposition becomes a verb. They undergo a transformation and there’s a prickly moment in which they exist simultaneously with both meanings.

I’m convinced this is what happens with animation – particularly methods such as hand-drawn and claymation, possibly explaining why animation formats are more likely to be viewed repeatedly. You see something which is obviously a drawn line, or a chunk of clay. But frame for frame it becomes an animal, or a little girl, or a splash. Its simultaneously one thing and another. Its like business built on the rule-of threes; the first iteration establishes, the second confirms and the 3rd rips you out of your expectation, and there’s a key element of timing so that there’s a moment of ‘hang’ where both meanings exist simultaneously. Except with animation, there’s no pay-off moment… just a lingering tingle that accompanies the film.

Its an hypothesis which I’d love to see tested. How might this be done? Well, I’m not sure. I don’t know if anyone’s been brain-scanned while listening to the above sentence, or while watching a comedy routine, but there’s probably a tell-tale flickering of activity. Hook up unwitting college students up and show them a filmed splash and a hand-drawn splash respectively. Then ask them if it tickles.

drops
Images from the incredible Joseph Gilland and here.