Sunday, 25 December 2011

Furaha in NRC again, but in English this time!

In June of this year, the Dutch newspaper NRC Handelsblad devoted a satisfyingly large section of their science section to the Furaha project. You will find the post on that subject here. As the text was in Dutch, the majority of the readers of this blog were unable to understand it. Mind you, I displayed the images at such a small scale to make it unreadable regardless of language; newspaper texts are not free, after all. But as time passes things change, so I asked Lucas Brouwers, the journalist who wrote the article, whether he would mind if I translated his text into English, and he in turn asked those in charge of such matters at the newspaper whether they would mind having the article republished in this form. The short answer was that no-one minded, so I went ahead and translated it into English. I tried to stay fairly close to the text, but at the same time wished to avoid the stilted style you often get in translations (it is much easier to write directly in a foreign language than it is to translate something from your own language into that language).

Click to enlarge; copyright NRC / Gert van Dijk

Hairy shufflers and radial flyers

BIOLOGY Professor of neurophysiology Gert van Dijk designs the flora and fauna of the fictive planet Furaha in his spare time.

Lucas Brouwers

At first glance the woolly-haired shuffler looks familiar. The animal looks quite a bit like a large mammal. It might just be a close relative of a rhinoceros, or a bison. But a closer look reveals that it is standing on six legs and that its upper jaw has grown into a grotesque shovel. Its more distant relatives are no less odd than the shuffler itself. There are six-legged predators, using their two front legs to knock their prey unconscious with. Or how about water animals, gliding solemnly through the oceans with hardly any moving parts visible from the outside. They are ingeniously designed: a hollow tube runs through their body, displacing water by pulsating continuously.

None of these animals are real. They are creations of Gert van Dijk, professor of neurophysiology in Leiden. In his spare time he designs the flora and fauna of the fictive planet Furaha, home to the woolly-haired shuffler. Van Dijk designed the workings of his planet in minute detail. From the evolution of life on Furaha to the place of the planet and its star in our galaxy: it is all there.

As a student Van Dijk used to paint extraterrestrial scenes for book covers for a publisher of what he now labels as "atrociously poor science fiction" The work did not make him exactly happy." That publisher asked me questions like the following: 'There is an empty corner in your painting; couldn't you fit in an exploding planet there?' ", he recollects.

Van Dijk therefore decided to start painting for his own pleasure. The first painting showing life on Furaha dates from 1979. It showed an exotic tree with an odd four-winged beast. That was only the beginning. Van Dijk: "Having painted a landscape with lots of grass in it, there obviously had to be something to eat all that grass. That was the start of the second painting. Well, once you have a animal eating plants, you are bound to need something to eat that animal in turn. That is how Furaha grew, and continued to grow."

A series of paintings followed. Later on Van Dijk started elaborating Furaha in other ways than using a painter's canvas. He writes essays on the biological background of his creations and simulates their anatomy using a computer. An astrophysics friend helped him to find a suitable spot in our galaxy for Furaha: in orbit around the star Nu Phoenicis IV. This star is of the same type as our sun and could therefore in principle support life.

Now, over thirty years after that first painting, the oceans and continents of Furaha are filled with life, there are detailed maps of the planet as well as descriptions of its climate. While there is a serious scientific background to the work, shaping the world flows from Van Dijk's fantasy.

This unusual hobby is known as 'speculative biology'. There aren't many speculative biologists. Van Dijk is familiar with most of the worlds they created. "There is the planet Nereus by Evan Black, there's Snaiad by Mehmet Kösemen and Epona, a collective project. There are a few projects dealing with the evolution of life on Earth in case the dinosaurs would not have gone extinct. That's largely it."

"There are certainly more people who wish to start a similar project", Van Dijk says, "but most do not combine a scientific background with artistic talent. Moreover, most projects stop after a few years' such as Snaiad, for the simple reason that they take up so much time. In fact, I stopped working on Furaha for years on end, but kept getting back to it. Fuaraha allows me to paint, write design and program. It meets to many of my needs to let it go."

Click to enlarge; copyright NRC / Gert van Dijk

How the woolly-haired shuffler came into being he no longer remembers in detail. "It's possible I had recently been looking at pictures of a rhinoceros. Things may just click together in my head. The inside of the skin folds of rhinos could well be covered in hairs, I may have thought."

That was the basic concept around which the animal took shape. "A skin fold covered in fur would be able to trap more warm air than one without hair. A fur coat, turned inside out, would have the same effect. That is in fact how the Inuit put their fur coats together", he explains. An animal with such furry folds would be able to deal with below-zero temperatures. And its shovel for a snout? "That evolved by itself".

In the end, Van Dijk painted the woolly-haired shuffler while it was upturning snow or soil in a search for plant roots or anything edible (see the cover). Its biology and ecology have been described in detail on Van Dijk's weblog. For instance, that says that the animal lives in small herds, and that that are small parasites living in the fur of its skin folds (trichophages).

Van Dijk does not use any fixed recipe to come up with a new life form. Sometime an animal crystallises around an interesting biological principle. The 'radial flyers', small creatures with four wings, came into being while he was sketching. Their wings are placed at an angle of 90 degrees to their body, like the blades of an helicopter rotor. The first sketches of these 'tetropters' showed a bilaterally symmetrical body , like a bird's, hanging under the wings. "That did not feel altogether right. I then thought it better to make the entire animal radially symmetrical, such as starfish or jellyfish."

In flight, the animals look a bit like helicopters as well. "Thanks to their design they have excellent manoeuvrability, but they aren't that fast in horizontal flight", Van Dijk explains. "The wings move in a figure eight-like pattern. A wing briefly beats against another one twice in every movement cycle. This creates additional lift". He explains calmly how this works. "Pigeons taking off do the same thing. Their two wings beat against one another above their backs. The contact between the wings does not only cause the characteristic sounds of pigeons taking off, but also causes extra air to be sucked in, and that generates an upwards force."

Van Dijk visualised the flight of these four-winged little creatures with computer simulations. The resulting flight of these radial flyers look looks organic. Their wings swing gracefully to and fro, rather like flags in the hands of a flagthrower. This mode of flight actually makes sense, as was proven by engineers a few years ago. With some pride Van Dijk wrote on his blog that they built a flying robot with four wings, flying in exactly the same manner as Furahan tetropters.

Another source of inspiration is nature on Earth. This is most apparent in those creation he labels as 'supercharged Earth designs'. One example of supercharging was his take on the undulating membranes of squids. "I started sketching animals with not two, but four of such membranes: two at the top and bottom, and two at the sides. From that design an animal emerged with a screw-like propulsion system."

There is no place on Furaha for unrealistic creatures. Ballonts, creatures that float by virtue of being lighter than air, may be struck from the record soon. Van Dijk: "I am beginning to think that balloon-like organism are not going to work. To keep them in I already increased the density of the atmosphere, but I do not really think that that is enough. That is a pity, because that would mean I have to abolish them."

No matter how exotic the Furahan fauna may be, most animals still look plausible and familiar. Why is that? Van Dijk: "That is an interesting question. Is the resemblance with life on Earth the result of a workable biomechanical design, or because many design models are simply prewired in my imagination?" He does not have the answer. One thing is certain, and that the resemblance is not introduced on purpose to make Furaha more palatable to his audience. Van Dijk: "I do not make any concessions to what people might like".

Making too many concessions is something he blames James Ccameron for, the director of the science fiction movie Avatar. Avarar takes place on the moon Pandora where there are six-legged animals, just like on Furaha. Wolves, horses and monkeys all have six-legged analogues on Pandora.

Van Dijk criticises their 'awkward' anatomy. "The horse analogues in Avatar have one pair of hind legs and two pairs of front legs, placed very close together. If you look carefully you will see that the two pairs of front legs move in synchrony. The designers simply doubled the front legs, so the animal looks in exactly the same way as a four-legged animal. At first glance they look cool, but essentially they are just horses with added frills."

The fact that Avatar is a science fiction movie is no excuse, Van Dijk thinks. "Of course, enjoying science fiction requires a degree of suspension of disbelief. But no-one ever claimed plausibility for the aliens of Star Wars or the sand worms of Dune, in contrast to what happened with Avatar. Cameron and scientists he hired claimed to have developed an accurate and biologically plausible world, and they simply did not.", Van Dijk says.

Obviously, Furaha reaches a fraction of the people of a Hollywood blockbuster. Van Dijk supposes that Furaha mainly attracts people with a higher education, interested, like he is, in what happens in the intersection of science and the arts. Still, he would definitely like to widen the readership of Furaha, for instance by publishing a book. In fact, he already posted a fake encyclopaedia of life on Furaha, including illustrations and infographics. He doesn't think there is a good chance of it getting published: "I do not know much about publishing books, but I guess that the market for such a work is very small."

You would expect professional biologists to be interested in a hobby that is so closely allied to their area of interest. Astrobiologists, dealing with the science of life on other planets, in particular might show an interest. But, apart from a rare exception, cross pollination between biologists and those working in speculative biology seems not to happen. Van Dijk: "They ought to like it in their heart of hearts. But perhaps astrobiologists do not wish to be associated with speculative biology. They are dealing with serious science and may prefer not to be to be portrayed as believers in little green men. Neither do I, by the way. I regard what I am doing as an intellectual and artistic game."

- (Left bottom pen drawing) Furahan fish developed variable numbers of jaws and fins
- (Underneath the block of six paintings) Top row, from left to right: many-legged grouillards, honeysucker, mowers. Bottom row, from left to right: landscape, phleph and worryw. All images: copyright Gert van Dijk
- (Right top) Tetropters generate extra lift by clapping their wings together in the same way insects and pigeons do.
- (Far right) Tetropters are very manoeuvrable and can let themselves drop very quickly. They cannot fly fast.

Click to enlarge; copyright Gert van Dijk

It is quite possible that some of the images are new to the readers. The one above, a phleph, has featured on the front page of the site at one time. Its formal name is Vanitas sursumvergenspropterpenuriaponderis, and yes, that does mean something...

Saturday, 10 December 2011

From the IFB archives (2): the marshwalloidea

The archives of the 'Institute of Furahan Biology' contain sketches of animals that later evolved into paintings (the sketches, not the animals) . This second foray into the deeper vaults of the archives reveals the development of the marshwallow, a large herbivore that like a hippopotamus spends much of its time in water. You can find the finished version on the land page of the Furaha site, and it is also visible in animated form on the 'walking with...' page.

Click to enlarge; copyright Gert van Dijk

I think this was the first sketch. I was experimenting with a new type of felt-tipped pin that was promised to behave as a brush. It did, largely, and that is why this sketch has such strong black strokes. The paper came for a stack used for polygraphic recordings, which is why it has yellow vertical lines on it. As you can see, the sketch shows an animal with a mane of hair standing in water. It has a somewhat bland expression on its face; perhaps it is wondering what it is doing there. The sketch does not show any underlying pencil lines but was done directly with the pen, which probably explains why the perspective isn't any good. Just look at the lower portion of its jaws: it is almost as if it is twisted to the right compared to the upper part of the head of the animal.

Click to enlarge; copyright Gert van Dijk

I did the same animal again later, this time with a pencil sketch overlaid with a version in blue ballpoint pen. The perspective works better here. The ballpoint pen version shows a smooth neck head shield protruding form the back of the animal's head. I must still have liked the brush-like pen, as I proceeded to go over it once more, this time with the thicker black strokes. The animal is still standing in water and still looks a bit daft, but seems to have a stronger personality than its predecessor. The complex shape of the head was the result of a conscious effort to avoid a typical mammalian head.

Click to enlarge; copyright Gert van Dijk

It may be difficult to see what is going on here. These are sketches in which I was searching for a pleasing composition. The theme is an animal standing in water, the surface of which is covered with lily-like leaves. The shadows show that the sun is behind the animal, so its shadow projects well before it. The sketch on the lower right is better in this respect, but looking back now I should have emphasized the diagonal nature of the composition.

Click to enlarge; copyright Gert van Dijk

This one shows the same idea, but the sun is now straight overhead. The lily-like thingies on the water surface are still there, but a new feature are the shadows of 'birds' flying overhead. Some of those are cast on the back of the animal itself. I wonder whether I would have succeeded with this approach: as the birds themselves would not be shown, would anyone be able to work out that those shadows were cast by four winged birds? 'Bird' is used here analogous to 'fish' in the Furahan context. For biological lay people, animal in water are 'fish', and for those people animals that fly are 'birds'. I know better, so do you, but that's how people are.
Obviously, I must have felt that the composition could be improved by just focusing on the head of the animal, as I not only went over the main lines there with a pen, but also divided that section of the sketch into 16 rectangles, a step that helps to redraw a composition in another format. That choice was chosen for the painting.

Click to enlarge; copyright Gert van Dijk

And here is the 'marshwallow' again in finished form. In this incarnation it looks irritated. I could easily have omitted all indications that we as humans read as emotional clues, and I probably should have. After all, it is not exactly likely that alien animals would convey emotions in a way that we can read. I probably liked it better this way...

Click to enlarge; copyright Gert van Dijk

Later, I thought about painting a herd of these marshwallows in the middle ground, being stared at by a predator in the foreground. For that I needed to think about a colour pattern. Here are two possible ones. The top one is very mammalian, but the second one is not. The shape of the limbs illustrates what happens if I do not pay a great deal of attention: they turn into mammalian legs. The hind ones especially go against the basic design of large hexapods, in whom the anatomy of the hind legs is -except for the feet- a mirror image of the front pair. In both, there are shoulder blades that are only loosely attached to the bulk of the body. The middle pair has a bone and joint connection to the corporal skeleton. For more on leg design, see previous entries in this blog: here and here.

Click to enlarge; copyright Gert van Dijk

Why have just one species of wallow? Indeed, shouldn't there be a group of related species, the 'walloidea'? I thought as much, and here are some. As you can see, there is a 'Protovolvulus species' at the right, in which males and females look the same. The one at the top is a male marshwallow, here called 'Disjecta membra', which means 'with strewn limbs'. The limbs that phrase refers to are not its own, but those of animals dumb enough to bother a marshwallow. In time, the name 'Disjecta membra' was replaced by 'Volvulus elongatus'. Some wallow species tend towards gigantism together with elaborations of the neck shields. Any resemblance with Ceratopsia is not coincidental at all. I have no idea why I came up with the name 'Disjecta pandorae', but to avoid any confusion I would like to stress that this sketch predates the film 'Avatar' by at least 25 years. 'Polyonyx vivax' seems to be the most elaborately coiffed wallow species. By the way, the gender symbols indicate that this how the genders look in the major portion of an animal's life. In most species, sex changes as a function of size and social importance, and 'indicator features' such as spikes on the neck shield change along with sex. It's complicated, I know...

Tuesday, 29 November 2011

Animals of the Future? Allons-y!

This is a short follow-up to the last post, on the project of my French friends & colleagues: 'Demain, les animaux du futur'.

Messieurs Boulay and Steyer wrote that they were quite happy to see that the post had generated numerous pertinent responses, so there.

More to the point, they decided to provide a bit more information on their website in the form of two new videos, on on the 'Demain...' project and one on the terraforming of Mars. It seems that the firm of Cossima Productions is off to a good start. Here is a direct link to the page where you can see both videos. From there, you can also click on the 'YouTube' logos under each video.


Here is the one where Boulay & Steyer explain what the project is all about. Mind you, the quality of the video on this blog is less good than the version you can see on the Cossima site or on YouTube, so if you want a higher quality, use that route or just go here directly.

Yes, it is in French; do not act surprised, it's what people in France speak. Perhaps I can be persuaded to provide a translation, but right away I haven't got the time to do so.

Additional text (December 2, 2011): With a bit of help by Marc in figuring out what they said I translated the text of the video. Any errors are my fault.

Sébastien Steyer:
"Marc and I both love science fiction. Every time we saw what films and other works in science fiction offered in the way of an exobiological bestiary, we had a thing or two to say about it. So, instead of criticising the work of others, we wished to create our own universe and to imagine speculative biology in Earth's future.
For example, we designed a future flightless parrot, in which we envisaged a reduction of its wings up to the point where they disappeared altogether, with an accompanying lengthening and strong development of its legs. Bit by bit we came up with an animal we thought likely, ten million years from now.
This is no longer science fiction, it's more like 'fiction science'. It is a projection, but one taking known evolutionary, tectonic and climatological models into consideration."
Marc Boulay:
"Making a sculpture, regardless of whether of a past, a present or a future animal, involves an anormous amount of work in getting source material and discussions with scientists. That takes up about 90% of my time. The rest is applying that knowledge. Doing the sculpture takes up about 10% of my time. "

Saturday, 19 November 2011

A future book on future evolution from France

Click to enlarge; copyright M Boulay / JS Steyer

Yes, there will be a new book on speculative evolution, a real proper book, that you can actually hold in your hands. It will describe life on Earth 10 million years in the future, or well after man. Future evolution on Earth is a branch of speculative biology I have hardly discussed in this blog, but I thought I would make an exception for this project. Do not run to the bookstore just yet, as the book will probably be published in the second half of 2012. This means you have about a year to brush up on your French, because that is the language it will appear in.

It will be entitled 'Demain: les animaux du futur' ('Tomorrow: animals of the future'), and will be published by 'Éditions Belin'. The authors, Marc Boulay and Sébastien Steyer, told me that they are currently working on the second of what will be five chapters. Marc is a digital sculptor and Z-Brush expert, who has an extensive knowledge of animal sculpture and whose work has featured on this blog before. Does anyone remember me posting on an exposition in Brussels where future animals were shown, posted in February 2009? Well, Marc proved to have had a hand in their design, as I later found out and discussed here, here and here. Sébastien is a palaeontologist from Paris, who does not limit himself to going on fossil-hunting expeditions in Africa and writing scientific papers, but took the time to write a -very readable!- book on 'Earth before the dinosaurs'. If you like that subject, you might wish to take a look the French or Dutch versions; an English version is in the works. Together with Pierre Godlewski they have formed a firm, Cossima productions, to produce not just the book but other projects as well, probably including a television documentary as well as a book. The idea for the project began in 1999 and is completely independent of 'The Future is Wild'.

So what will be in the 'Demain' book? Obviously, we do not know yet, but you can get some glimpses at the site of Marc Boulay and of Cossima Productions. Perhaps the animals that were once shown on their sites will appear in the book. As these sites have been shut down, only some hints remain here and there, including on my own blog.

Click to enlarge; copyright M Boulay / JS Steyer

I really liked Benthogyrinus. The accompanying text says that it about the only surviving amphibian, a descendant of the frog species Xenopus. It has developed glands to expel salt and now lives in the seas. It reproduces in its larval stage and exhibits profound sexual dimorphism, i.e., males are much smaller and are shaped differently than females. For more images on this animal please read the original post.


Above is a demo reel of Diatrymimum boiseï, obtained from the links above. It is a large predatory bird, that has not just lost the power of flight but has lost its wings altogether, bones and all. It evolved from a parrot (Psittacus). As you can see the authors did their homework: whereas most people would limit their skeletal studies to some sketches, in this instance the skeleton has been worked out in full 3D detail. From then on the video shows how the body is shaped, and after that there are some colour studies. The background, with iits light to dark gray gradient, is typical for ZBrush. As a whole the demo shows what can be done with ZBrush (if you are a very accomplished 3D artist, that is!). What struck me is that the femur (the thighbone) is not horizontal as in ostriches but is oriented much more vertically, making the limb much more reminescent of that of a predatory dinosaur such as Tyrannosaurus. Such dinosaurs can afford to have their limb in this position because their tails balance the weight of the front part of the body, meaning that their centre of gravity is near the hip joints, and as long as the feet are directly underneath the centre of gravity, the animal won't keel over. Ostriches do not have heavy tails, meaning their centre of gravity is well in front of the hip joints. In order not to fall the feet still have to be underneath the centre of gravity, and the ostrich does that by having its thighs in a more horizontal position than Diatrymimus. I think Diatrymimus gets away with this by having a short and rather small body.


And this demo reel shows more of Marc's ZBrush work. There are ants, Burgess shale animals as well as dinosaurs and other Mesozoic animals, but about 40 seconds after the start there are glimpses of animals that may well be future animals, but whether they are part of the project described above, I do not know. Perhaps the authors will let us know. At any rate I will keep you informed when the book comes out, hopefully a year from now.


Additional remarks (November 12 2011)

Marc sent me an email that he was happy with the post and added a file of a much better quality video. I agree that the videos I had shown you were not very good. The problem was not the source material, which was excellent, but in getting that quality here on the blog. The Google blogger program alters videos and shrinks them to fit one and the same size. Unfortunately, I cannot therefore replace the videos above with better ones. But what I can do, and should have done, is to point out where you can find better quality ones.

Both videos can be found on Youtube: here is the Diatrymimus one, and here is the 2010 demo reel.

Marc also added some other images for you to look at:

Click to enlarge; copyright M Boulay / JS Steyer

This is D. boiseï again, this time with lots of details of the head. I suppose that readers will have noted the development of teeth-like structures, lost by its bird ancestors a long time ago? The two commenters so far drew attention to the lack of feathers. I can understand how feathers might be lost on the head for predators: many vultures have unfeathered heads. But there is as yet no explanation for the total loss of feathers elsewhere on the body. We will either have to wait for the book, or perhaps Marc or Sébastien will take the bait and write a comment...

Click to enlarge; copyright M Boulay / JS Steyer

And a new species as well! It is called 'Spatamagnalis ruber'. If memory serves me right, a 'spata' is a short or broad sword, and ruber is definitely 'red'. Apparently, there are more flightless birds in this future. And featherless too... is it the climate?

Saturday, 5 November 2011

From the IFB archives (1): the 'schaatsbeest'

Every institute has archives. You cannot have a proper Institute with a capital 'I' without them. The 'Institute for the Advancement of Biological Studies on Furaha, Nu Phoenicis IV', also known as the 'Institute of Furahan Biology', or even shorter as the 'IFB', definitely has archives. You might think that the IFB, being a virtual Institute, would have virtual archives, but that is not the case.
I have a stack of old sketchbooks and loose sheets of paper containing sketches that I have amassed over the years. As archives go, this one is a right mess, as the papers are not in any order and the dates of the sketches and studies are not indicated. Some sketches contain the earliest appearances of animals that were later painted, others are just doodles, some contains ideas later incorporated into something else, and some show designs that never made it. I thought it might be interesting to show a few of those sketches, and will start with an example of the latter kind, one that nearly made it into a painting, but became destined for non-existence. So here is the world's first peek at the 'schaatsbeest'.

Click to enlarge; copyright Gert van Dijk

This is probably its very first appearance. I must have felt the composition was good from the start, as it hardly changed afterwards. In fact, I still like it. I wrote 'schaatsbeest' next to it, which is Dutch for 'skating beast'. For this post I decided to leave its name in Dutch rather than translate it into English. There are animals names in Swahili and French besides English on Furaha, so why not one or two in other languages? On the remote chance that you might wish to pronounce its name correctly, the 'ch' in the beginning is like the 'ch' in 'Bach' as Germans pronounce it, which is NOT 'bahk'. The 'aa' is like the 'a' in 'father' but longer, and the 'ee' in 'beest' is like the 'ay' in layer (if you think this is silly, remember that you English speakers are the ones who messed things up with your great vowel shift). Anyway, the schaatsbeest is ice sailing, also known as 'ice yachting'. If you do not know what ice yachting is, have a quick look at the Wikipedia entry, or here for photographs of present-day ice sailing.

Click to enlarge; source here

Just to be on the safe side, here is an example of a historical type of ship used in ice yachting. As you can see, the process is like sailing, but instead of a hull making its way through water there are skates allowing it to glide over frozen rivers, ponds or lakes.

Click to enlarge; copyright Gert van Dijk

And this may well have been the second sketch. Together with the first one it allows the beast's anatomy to be discerned: it has six legs, of which four are used to skate on, and the other two look like the front limbs of a mantis (this may very well be the first time that this particular configuration came up). There are four sails, derived from wings. The animal is sailing into the wind, which means that the wind is coming from in front and a bit to the side. This type of sailing requires the sails to be very taut, and results in large sideways forces on the ship, so ships sailing into the wind typically tilt over to the leeward side. The schaatsbeest undergoes the same forces, and in this case the two skating legs on the windward side are tilted right off the ice, where they help act as a counterweight.
The point of this second sketch was to work out the perspective. If you look carefully, you will see that the animal throws a shadow on the ice, indicated by vertical stripes, and below that you see its body mirrored in the ice (the perspective of a mirror image is easy, once you understand that you should act as if there is a second object behind the mirror). In this case, the mirror image allows the viewer to see the underside of the animal. I thought that this would make for an interesting composition.

Click to enlarge; copyright Gert van Dijk

This sheet of paper shows more takes on the same idea. I used to sketch multiple images right through one another at the time. I was playing with the sails and had a first look at colour. The colour sketch at the top shows a completely different kind of sail, reminiscent of a schooner rig. The bottom sketch shows two pairs of sails while the two other sketches show fused sails, with a mainsail at the back and a jib or genoa in front.

Click to enlarge; copyright Gert van Dijk

Here is a pencil sketch showing the schaatsbeest from in front. The odd object at the left is a squarish 3D arrow indicating the wind direction. The animal allows its body to be tilted, but uses its front limbs and the windward skates to balance it. Its head is held perfectly horizontally. The sails are also moved towards the vertical. I think that the thick lines where its back meets the mainsail masts were alterations to allow it do that with sufficient force. The small sketch towards the right show it sailing squarely before the wind, where it does not tilt and spreads out its four sails to make the most of the wind.

Click to enlarge; copyright Gert van Dijk

Finally, a very large pencil sketch. It looks like it is drawn on parchment, but that is only because I needed to manipulate the image for the pencil lines to show up at all. I had made a cardboard model, put it on a mirror, and based the sketch on that. That explains the thinness of the limbs and the lack of any perspective drawing guides.

I stopped development there. In hindsight, I may have been right to do so. While I still like the composition, almost enough to pick up the design again, an ecological point of view suggests this animal to be in trouble. It is obviously quite well adapted to move around on expanses of flat ice. Are these then around from most of the year? What does it find there to eat? The animal would probably be very clumsy on dry land, and its modified wings will not allow it to fly. Oh well; back into the archives, I guess.

Saturday, 22 October 2011

Lifting the cloak on Cloakfish

There is an odd difference between drawings and photographs of animals. In a photograph a galloping animal may be caught in time in just such a way that only one of its legs touches the ground. No-one will think twice about whether this is 'correct' or not. But do the same in a painting, and people will start thinking that the painter has it all wrong. Something like that happened to my Furahan Fish IV, shown in this blog earlier.

Click to enlarge; copyright Gert van Dijk

Here it is again. I received some questions where it right front fin had gone. Was it amputated or had I forgotten it? No, I replied, I worked out the perspective and the missing fin is simply hidden by the body. I admit that I saw these people's point and have been tempted to tweak the perspective a bit and have the tip of the 'missing' fin emerge from behind the body. Its absence seems to be disturbing in a way. While working on Fish and Cloakfish I experimented a bit with the reasons.

Click to enlarge; copyright Gert van Dijk

This image shows two versions of a ray-like species of Fishes IV. The top image shows a layer for the perspective lines as well as a layer containing some rough idea of light and colour. Layers, for those of you not familiar with computer painting programs, are the computer equivalent of a pane of glass on which you paint. The painting as a whole can consist of many such panes, each consisting a different bit of the painting. The trick is that you can make layers invisible, change their transparency or swap their order. I use Painter 11 as I like its tools, that resemble artists' brushes more than the tools of Photoshop CS5. As you can see from the sketch the perspective effect is fairly strong, meaning that parallel lines diverge quite a bit. Still, the drawing seems to work, perhaps because all parts of the animal are visible.

Apart from 'regular' Fishes, I have been working on Cloakfish, completely unrelated to Fishes I to VI. You will find cloakfish on the main Furaha page, but also here on the blog. Apart from a few sketches almost all my earlier work on cloakfishes involved computer graphics, because I wished to see their four 'cloaks' move while swimming. At present it is time to paint them, but I wished to get their cloaks right, and doing that by hand would be very difficult. So I took recourse to computer graphics, a process best described as 'practical' ('cheating' comes to mind, but why not use tools when available?). To help the process, I adapted earlier programmes in Matlab so I could produce a cloak with any shape I wished, as on the left, that is warped to produce waves progressing along it, as on the right. Right; make four of them, export them as 3D files, import them in a suitable 3D program (Vue Infinite in my case, and we are ready to play.

Click to enlarge; copyright Gert van Dijk

Here is an example. The left panel shows the four cloaks, striped to help visualise their 3D shape, attached to a central axis (that is called a 'dagger', by the way). The body proper is formed by some basic shapes such as cylinders and rectangles. I thought it might be worthwhile to put lots of parallel rods in the image that could help get a better feel for the perspective. I set the focal distance of the imaginary camera in Vue to 35 mm, and that is the image in the left-hand panel. The perspective looks believable, does it not?

The right-hand side was produced in Painter 11. I imported the image from Vue and painted a rough cloakfish on a semitransparent layer above it. I decided to play around with the front edge of the funnel. In that stage of their evolution, cloakfish were all filter feeders, so the opening in the front doubles as a food and a respiratory intake. Some cloakfish evolved feelers, and those are what you see here. I wasn't happy with the sketch though, and wondered whether the perspective was part of the problem.

Click to enlarge; copyright Gert van Dijk

So I went back to Vue, altered the characteristics of the 'camera' to give it a long lens, and repeated the process. Well, well. The result looked more suitable for an illustration that the earlier one, even though that one was realistic. More realistic, because the combination of the lens with the size of the animal resulted in a perspective closer to what you would see if you were a human on Furaha. Obviously, my attempt at 'mathematical correctness' did not work. Perhaps it can be as counterproductive as its political counterpart. Anyway, I was not happy with the funnel opening.

Perhaps it was time for a redesign. Should cloakfish really all be filter feeders? There certainly are small filter feeders on Earth (polyps etc.), but there is curious gap in size in filter feeders: either they are small or they are colossal, such as whales. I cannot think of sardine- or tuna-sized filter feeders. While I haven't thought that problem through, it seems a real one. I wanted cloakfish to occupy lots of niches and needed a good range of sizes. Perhaps the beasts needed a separation of alimentary and breathing tracts after all.

Click to enlarge; copyright Gert van Dijk

Here is an all-new cloakfish. The inner body protrudes forward from the funnel, that, as before, contains the gills. I played with it having four jaws, but decided against it. What you see here is the latest thing in cloakfish design: a regular mouth with a horizontal split. It need not stay that way, though. As you can see, their eyes have shifted forwards on the funnel to improve frontal vision while still having excellent all-round vision. And the perspective? Well, a view without strongly convergent lines, such as this one, may help viewers get a good feeling for the animal's shape.

Saturday, 8 October 2011

From kudu to bogorbes

There is too much going on at present for me to write any blog entries on arcane biomechanical biomechanics on other planets. For once, I will focus on some personal aspects behind a Furahan animal, an idea suggested by two anniversaries of past events. Twenty years ago I visited sub-Saharan Africa for the first time. I wished to see animals in the wild, reasoning that the slow degradation of the world's biodiversity would render such visits meaningless in time. I wasn't wrong about the degradation, but it is not too late for a visit yet.

I had a great time, camping in the wild, seeing animals as they are supposed to be, and revelling in an over-abundance of beauty. Any readers who have been to Eastern of Southern Africa may recognise African influences in my paintings.

Click to enlarge; copyright Gert van Dijk

Here is a sketch proving the point: a group of predators is enjoying their meal on a steppe or savannah, watching some large herbivores and being watched in turn. The scientist in me insists in adding that this is not a typically African scene: similar scenes have been played out on European, Asian, American and probably Australian steppes and savannahs countless times, with different species in the prey and predator roles for each time and place. But it is only in Africa that such biomes have not been wholly replaced by wheat fields, livestock pastures or the human habitat, explaining the strong association of such scenes with Africa. In my case, the associations have a strong personal flavour as well.

That visit changed my life because I met my wife to be during that trip. We got married a few years later, and visited Africa several times afterwards, something I stopped doing after she died, also quite some time ago. At the time she was as enamoured with the wildlife as I was. I returned home earlier than my travel companions, and immediately sent off countless rolls of film to be developed (it was 20 years ago). I sent a few prints to my fellow travellers, and decided to tweak one I would sent to my later wife in Paris, where she then lived.

Click to enlarge; copyright Gert van Dijk

I took out my oil paints and altered a photograph of a greater kudu, an antelope, standing on the shores of Lake Bogoria in Kenya. I added a third pair of legs in the front as well as a new neck and head, and masked out bits of leftover kudu. I varnished the photograph so my handiwork was not too apparent. I sent my 'cooked kudu' to her, and she had a good laugh with it. She mixed the photograph with photographs of her own of that trip. A friend of hers went through her stack of vacation photographs, said "Tiens, il y a six pattes" ("Hey, there's six legs") on encountering the photograph and then simply continued flicking through the pictures, without apparently realising that a large six-legged herbivore was more than just a trifle strange, in Africa or anywhere else...

My wife later dubbed the animal a 'bogorbes' (Venia lauta), and it has been part of the Furahan fauna ever since. You will find it on the cover of Sigismunda Felsacker's travelogue "Paleo Days" (see the New Hades book shop), and the blurb text there was written by my wife; not everyone in the Furaha universe is fictional.

Saturday, 1 October 2011

"Maybe if you stick on another leg at the end of the tail?"

Designing a novel way of walking for extraterrestrial animals is complicated. I tried my hand at designing gaits for large hexapodal creatures (see the main Furaha site), radial walking patterns and also explored walking with an odd number of limbs. In all such efforts the trick is to achieve something that looks interesting as well as believable. In the context of speculative biology 'believable' is balanced somewhere between 'Earth normal' and weirdness. One thing is clear though: you cannot get a believable result by assembling an animal of leftover bits and pieces, such as just sticking an extra leg on the end of a long tail.

Or can you? As usual, evolution on Earth manages to come up with designs that, if invented by a mere human, would fall in the category of unacceptable weirdness. The following video shows an insect that looks odd, but oddness by itself is fairly normal for insects. Look how it moves: most of the time insects walk with a double tripod gait: the front and hind legs on one side move in unison with the middle leg on the other side. When these three legs touch the ground they form a stable tripod. The other three legs meanwhile are lifted and swung forwards, and when they touch the ground, they will form a tripod as well. The two tripods are exactly out of phase, so when one hind leg is on the ground the other should be in the air. Now have a look at the hind legs of this interesting beastie, a trilobite beetle from Borneo. The original is here.


Its pairs of legs are in phase, a bit unexpected, but slow-moving insects can do that. But that is not all: it uses the tip of its abdomen as an additional unpaired leg. It curves its abdomen forwards, plants its 'leg' on the ground, and pushes backwards with it. Anatomically this may not be a proper leg, but functionally this animal certainly uses seven legs: it's a heptapod!


Here's another video. The beginning shows that this species can also walk with the front legs out of phase, but you do not get to see all legs that well. It is clear though that it uses the end of its abdomen as a seventh functional leg.

Why do these animals walk in this weird fashion? The gait does not look quick or agile. In fact, the animals appear to be rather slow and clumsy. A bit of research points to an answer. These 'trilobite beetles' are said to belong to the genus Duliticola, and using Google with that name results in a paper starting with the brilliantly surrealistic sentence 'There are two trilobite larva species in Singapore.' Apparently, the male and female of these species differ greatly in shape: the males look like typical beetles while the females are neotenous. Now neoteny is a condition in which sexual maturity occurs while the body is still in a larval stage. The axolotl is a famous example, and humans are sometimes thought to display neoteny as well.

But what does that mean for the strange gait of this apparently female insect? Well, it looks a bit like a regular adult insect, with a hard exoskeleton and all, but its general body shape is in fact that of a caterpillar. Caterpillars display complex gaits, not too surprising if you think about their body plan: six regular legs that will become the legs of the adult insect, a number of 'prolegs' (the knobby stumps further along a caterpillar's body), as well as final 'anal prolegs'. All of these are attached to a boneless body, providing endless opportunities of combining walking with stretching of the body. So that explains the trilobite beetle's walk: its' a caterpillar in disguise. Never underestimate insects' capability of oddness.

There is of course more to be told about caterpillar movement. In fact, at least in some species their gut moves inside their body before the outside follows up. The following video show that very nicely as well as the combination of body stretching with using legs. Perhaps there is a risk that you will learn more about caterpillar movement that you bargained for, but personally, I love details.


Sunday, 11 September 2011

It's a bird, it's a plane, it's a... flying squid!?

A year ago images of flying squid were in the news, including two short papers in Scientific American (here and here). Somehow I missed them at the time. Perhaps they are old news to readers of this blog, but I thought they were still very interesting. After all, cephalopods (octopus, squid and the like) attract attention from just about everyone with an interest in speculative evolution. I think Dougal Dixon was the first to have them venture out on land, a concept followed so often that it has become a cliché (but which does not mean that it was not a great idea at the time). I criticised the concept of 'walking with tentacles' in a series of blog entries later, reasoning that tentacles are so poorly designed to withstand compressive forces that evolution would turn them into limbs (here are the first, second, third and fourth posts on the subject). By the way, cephalopods with jointed legs would, for me, be much more interesting than ones painfully plodding about on tentacles. Unfortunately, their renal system is probably a much larger hindrance from them leaving the water than having tentacles; but I digress.

Cephalopods have jet propulsion, also a rather interesting feature to have aboard, and one that also crops up regularly in discussions on alien animal design. Some went so far as to equip animals with fuel-burning jets, something belonging in the needs-a-lot-of-faith category.

So now it turns out that some squids can leave the water, much as flying fish do, and probably for the same reason: to escape predators. And they use jet propulsion to do so. I wonder how people would react if squid did not exist and I would invent an animal with a double set of propulsion organs, fins as well as a jet: "What, two means of propulsion? That is improbable and inefficient!" Have that followed by the remark that they can also use their fins as wings and fold up their grasping organs to have a second pair of wings: "He's lost it this time!". Facts are often stranger than fiction, and flying squid are a prime example.

Internet searches revealed more pages and photographs of flying squid,including the following two ones. I checked two books on cephalopods I already had, and one book mentioned that the family Ommastrephidae is in fact known as 'flying squids'. The other book specifically mentioned that the fins are 'not especially well modified for gliding'. It seemed I had missed all of that.

This is a large image found here; The blogger program would not let me import all of it, so I had to cut off portions not showing squid. Even so, you may have to zoom in to see them properly. Some squid trail a stream of water behind them, that appears to be breaking up into drops in some cases. The text mentions that these images were taken as a series of rapidly taken images, and that this time series allows calculation of how fast the squid moved. That is obviously true, but unfortunately the results of those calculations were not stated, which is frustrating.

Click to enlarge; from: Bartol et al, Integr. Comp. Biol. (2008) 48 (6): 720-733

Squid squeeze a jet of water out of a tube, the 'siphon'. The image above nicely shows that the siphon can be turned around allowing the squid to move in either direction. The fins at the end of the body are a normal part of squid anatomy. Squid use both their fins and their jets to move around. The principle of jet propulsion has to do with actions and opposite reactions: pushing away a mass with a certain force results in you undergoing an equal force in the opposite reaction. The force gets bigger the more mass is pushed away and the faster it is propelled. In jet engines air streams in to the engine and out of it continuously, but in squid the propulsion is 'pulsatile'. The water is held in the mantle cavity, surrounded by muscles; when these contract water is forced out. Afterwards the muscles relax, the cavity expands and sucks in water for the next cycle. On the whole squid jet propulsion is nowhere near as efficient as swimming with a tail is, as fish do. Recent calculations suggest it is not as inefficient as formerly thought, but squid still do well do use their fins as well as their jet propulsion system. In fact, they may be better off for having two propulsion systems. I found some interesting material on that subject in a free scientific paper on the subject (from which I took the diagram above as well).

Click to enlarge

This image, found here, shows one flying squid in close up. The animal is flying towards the left. The image suggests that the fins are held in a V-shape, with the tips directed upwards. Holding wings like that is a design trick to prevent rolling about the body axis: when the animal rolls to one side, the wing on that side becomes more horizontal, so it will generates more lift. The other wing becomes more vertical and generates less left. The two effects counteracts the roll and help stabilise the body. At the other end of the animal the tentacles are held in a symmetrical way in a horizontal plane, and there appears to be a membrane between at least some tentacles. This position can only mean that the tentacles act as another wing. I cannot see on the large image whether the tentacle-wings are held in a V-position as well. The close-up seems to suggest they are not. So the 'flight plan' of the flying squid consist of two pairs of wings positioned far apart, with a long body between them. Now where have I seen that before?

Click to enlarge; copyright Gert van Dijk

Actually, only here, as far as I know. The Furahan Seasoar can be found on my website. I developed it consciously in an effort to see what could be done with a four-winged body plan. I reasoned that placing the wings far apart would place relatively much mass at the ends of the animal, making it more difficult to rotate to the left and right. The design would be stable, though, good for long and energy-efficient flights. In fact, I made a paper version once that flew quite well (which gives me an interesting idea for a future post...). The front pair of wings are held in a V-shape, but the hind pair are not. In truth, I did that only because it looked good, and I never stopped to think why one pair should be held in a V-shape and the other not. That arrangement looks a lot like that of the flying squid. Perhaps it does serve a purpose besides looking good.

The large image shows trails of water behind the squid. Does that mean that the squid are actually using jet propulsion to power their flight? Yes and no. Maybe. On the one hand it is certain that the jet allowed them to accelerate enough to leave the water, where resistance against movement is very large. That same force should have a stronger propulsive effect in air, which offers much less resistance to movement than water. On the other hand, weight is not a big problem in water, but it is in the air. Any water carried into the air to serve as 'ejection mass' for jet propulsion increases the mass of the animal and will therefore impair the squid's flying ability considerably. The good part of that is that the water is squeezed out, so the mass of the squid plus its store of water decreases quickly. As the store of water is depleted the squid gets an extra boost, which helps to propel it. There must be a complex optimum in there somewhere, in which the mass of stored water, the force of propulsion and the moment the squid leaves the water are all factors that, when balanced subtly, result in the best soaring ability. But such thoughts count in the long run of evolution. For an individual squid with a predator on its heels (so to speak), getting out of the water NOW regardless of any optimisation might be the wiser choice.

Friday, 26 August 2011

Between the Morae River and the Red Valley

I discussed Brynn Metheny's 'Morae River' project once before in this blog. The project dealt with life forms in a certain geographical area called 'Solturna'. The animals there at first glance looked like Earth's mammals, reptiles, or fish, so you might think that the Morae valley might be somewhere on Earth. But a closer look revealed small but telling differences in anatomy, so you might think that the creatures perhaps stemmed from a not too alternate time-line and were mammaloid, reptiloid and ichthyoid. But a few animals departed so much from regular Earth stock to make you think that they required an extremely early divergence or an unearthly origin. Brynn gave no clue as how to place her creations, and preferred a fluid interpretation. Earlier this year she unfortunately decided to stop working on the Morae River. But that should those who never visited the site from doing so, as it is a great project even if it is no longer updated.

Luckily she did not stop producing odd animals. Far from it! I gather that she is making 'creature design' her career, which hopefully means that there is much more to come. There are several places where you can admire her work: she has a site on Deviant Art where she goes under the name of LenoreKitty. She has a site under her own name,, as well as one going by the name of Fishhook studio. I selected a few paintings for you to see here, and expect that they will make you hungry for more.

Click to enlarge; copyright Brynn Metheney

The pygmy esorifleu
As you can see, this is an arboreal creature with a strong bill, like a parrot's, and six limbs. The middle pair are placed at the top of the animal and are directed upwards, whereas the front and aft pairs are directed downward. There is also a tail, which looks like it is prehensile. This animal can only be a brachiating carnivore. It looks somewhat like my marblebill, to be found on the Furaha site but also in this blog (here and here). A fairly large design difference is that the esorifleu using its middle pair of limbs to swing from, whereas I chose the front pair. Brynn wrote me that the pygmy was designed for a creature design contest. I think the marblebill and the esorifleu are nice examples of convergent speculation.

Click to enlarge; copyright Brynn Metheney

Elegant hunters
And indeed they are. Mind you, the prey look rather dashing as well. The beaks of the hunters remind me of the mouth of a deinichthys. At first glance their body design seems to say 'bony fish from Earth', with its vertical tail, fin rays, gills and dorsal fin. But then you notice that instead of one pair of pectoral fins there are two, giving a jolt to the idea of what exactly they are. What I do not know is whether you have to know that two pairs of pectoral fins are impossible for that jolt to occur. Anyway, four gill slits is an unusual number as well.
I would like to see more of their prey, whose 'Bauplan' seems much more unearthly. I like the bumps on the front of the flippers. Not many swimming animals have those, but humpback whales have very knobbly leading edges on their enormous flippers, and in their case the turbulence they cause actually seems to help. Is that the end of a siphon I see on their sides? Are those expiratory outlets?

Click to enlarge; copyright Brynn Metheney

No classification problems here: that's a perissodactyl unguloid, or a hoofed animal with an odd number of toes. But are those concentric structures external ears? Perhaps the animal is not Terran after all...
What I like a great deal about this one is how the animals are not simply shown in side view, but are much more three-dimensional. The calf's head cannot be seen, and the mother's head is turned away a bit as well. This is where the trained artist shows herself, I think.

Click to enlarge; copyright Brynn Metheney

A work in progress
Lacking a name, let's call it a 'wip'. If I see correctly there is just one pair of eyes, and the other markings on its head are nostrils and ears. Even so, this animal is more alien than the previous one, with the sail on its neck and particularly the spikes at the base of its tail. Now what are these doing there? They are not placed well for attack or defence, so perhaps they are for display purposes, and display to members of the same species always boils down to sex. Do the spikes serve to impress other wips, or do they provide tactile stimulation during procreation? I had better reign in my imagination here...
It's a beauty though.

Click to enlarge; copyright Brynn Metheney

Another work in progress
If it is, we might as well label it a 'wiptoo'. It is interesting how this head and neck study immediately evokes the notion that we are looking at a very large animal. One reason must be the relatively thick neck. Large animals need proportionately thicker limbs, and that goes for necks too (see here and here for the reasons). Apparently we are so used to seeing the results of these laws of nature that we immediately draw conclusions from seeing their results. Alternatively, of course, this could be a moderately sized animal from a heavy-gravity world, but I do not think so: its eyes are also small in relation to its body. They seem to be camera eys such as vertebrates have on Earth. While bigger animals generally have bigger eyes, eye size does not increase directly with body size, so large animals have relatively small eyes. As with neck thickness, the observer takes these cues and judges the size of the animal, consciously or unconsciously.
Its skin glistens. You can tell from the linear nature of the reflections that its skin is smooth, and I wonder whether it is wet because it just emerged from a swamp or something similar or because the skin itself is wet or oily. A large animal with a permanently wet skin would need a permanently moist and saturated environment. Perhaps it lives as brontosaurs were once thought to do: in humid steaming swamps.

Click to enlarge; copyright Brynn Metheney

There are no animals on this painting, but the image contains a promise. The website of the Red Valley project is already up, but there's not much to see yet. We are promised that animals will appear there in the Fall, so hopefully Brynn won't keep us waiting too long. She wrote me that she is not going to reveal all about the planet: "I might know details about the whole of the planet and such but as far as my viewers are concerned, I'd like it to just be about this valley." I agree with that sentiment: always leave the viewer or the audience hungry for a bit more, and a hint that there is in fact more does wonders to whet the appetite. She added: "I want the flora and fauna to feel alien enough but I want viewers to relate to them as well."
From what Brynn has done in the past, I think she will succeed. The text on the Red River site also states: "No regions, no classification, just this place as it is." Oh very well, I get the message: I should stop trying to classify these animals to see where they belong and what makes them work.

Hmmm; as if I could...

Saturday, 20 August 2011

It's a Fish! (yes, again...; this one's in 3D, though)

Click to enlarge; copyright Gert van Dijk

This is just an extra post. Regular readers may remember that I tried my hand at ZBrush in the past. I still try it from time to time, but found that it, as everything, takes time to master, and digital painting takes precedence. The ZBrush people keep out churning new options, so I will probably never get around to mastering even the simpler elements. Pixologic, the same firm that produces ZBrush, now offers a similar program but completely free: Sculptris. It offers only a few controls, which really helps to learn it. It is very impressive. The controls are the same as those of ZBrush, so experience with one program helps the other. I could not resist trying it, and found it a pleasure to work with. Go to the Pixologic site to see what can be done with it, because my meagre efforts only show what you can do with it in one evening. It is very useful for 2D artists who do not plan to go into 3D, becaue it is easy to sculpt a rough shape to help get the perspective right.

Click to enlarge; copyright Gert van Dijk

So here is a Fish, of the Fishes IV type; I showed one before. I painted four now for The Book, and will not publish these paintings here on the blog. But having done that, Fish IV anatomy came natural to me, and here it is: six flippers, usually attached higher on the body as you go aft, a large head merged without a neck to a stiff body, and three gills on each side with separate inlets but a fused outlet. You knew about the four eyes and the four jaws. As I said, typical Fish IV anatomy.

Click to enlarge; copyright Gert van Dijk

Click to enlarge; copyright Gert van Dijk


P.S. As Luke remarked in the comments section the Fish shown so far are fairly large. Aren't there smaller ones? Yes, there are. I had realised I had a tendency towards larger ones, so I explored the possibilities of size on purpose.

Click to enlarge; copyright Gert van Dijk

Here is a rough sketch in Painter11. Its smaller size is indicated by relatively large eyes and by having thinner flippers, that as a result resemble fins more (the second pair are probably too large). I also experimented with a general 'fishy' look by giving it a glistening skin. The counter-colour pattern (dark on top, pale below) is probably a universal trick to blend into the background.