Saturday 30 January 2010

Anatomy of an Alien V / Greenworld I

This is the fifth and final post on the 1997 BBC documentary 'Anatomy of an Alien / Natural History of an Alien. Just like the previous instalment, this one deals with the work of Dougal Dixon. Although I did not plan it this way, keeping this one for last turns out nicely, as yesterday (January 29) Dixon's brand new book on Greenworld was published in Japan. More on that subject later, which explains why this post is also called 'Greenworld I'. Meanwhile, don't go rushing to your local book store to buy the English, French or whatever versions, as there aren't any. You Japanese readers, please do rush out now and buy ten copies each, so the publisher may give the rest of us an English version.

The video fragment is shown below. It does a good job of showing the evolutionary origins of the two major animal groups on Greenworld. Their common ancestor was a starfish-like animal with radial symmetry, but, unlike Earth's starfish, it had six legs, not five. When these animals came out on land they had not yet developed beyond radial symmetry, and still had no hard skeleton. Their solution was to use massive clumsy muscles first, but they developed a more practical skeleton later. In effect, their legs more or less started out as tentacles but developed into proper legs, much as I explained in my series on 'Why there is no walking with tentacles'. These animals secondarily developed bilateral symmetry. In one group the plane of symmetry came to lie in the groove (sulcus) between the legs, so the animals ended up with three pairs of legs; these are sulcosyms. In the other lineage the symmetry plane neatly divides an arm ('brachium') on one end of the animal and another at its other end. These are the 'brachiosyms', which therefore have two unpaired legs, one at the front and one at the end, as well as two pairs of legs in between. Those who have already watched the video at the end of this post may have noticed that not everything I have written here is mentioned in the video, so how do I know this? Well, Dougal Dixon sent me some notes and sketches on Greenworld a long time ago, and that's how. Mind you, the names might have changed since then, because this was 20 years ago...

If you search the internet you will find bits and pieces of Greenworld here and there, probably because the book has had to wait such a long time before it was published. Puyamaster from Japan, whose comments you can find following the two posts before the present one, searched more diligently than most and came up with some interesting material. Here are some of the things he found (with thanks!).

Source unknown

So there are (or were) models of some Greenworld animals. One is an 'anteater-sized insectivore (or equivalent)'. It is also visible in the video. My notes say it is the biggest of the brachiosyms.

Source unknown

Aha! Jack Cohen, also featuring in 'Natural History of an Alien' (and featuring in previous segments, such as the one on 'Europan waters', is shown holding some Greenworld models. When it comes to biologically sound aliens Jack Cohen is undoubtedly one of the usual suspects to round up, so his appearance here is not surprising. Still , I wonder what the occasion was.
Puyamaster provided the web addresses of these photographs; their original sites are here and here. I would be curious to have a look at the site they are meant to illustrate; usually this is a simple matter of successively cutting off the end of the address until you find a readable htm file, but that does not help here. If anyone does know where these picture are from, I, and presumably others too, would be interested.

In a next post I will write a bit more about Greenworld. Here I would like to finish with some thoughts on the alien nature of radial symmetry. I guess that many of those designing alien animals consciously search for features to strengthen the 'alienness' fof their creatures, and radial symmetry has that in abundance. In discussions on the subject some seem to accept it as an acceptable body plan for big and possibly intelligent animals, whereas others dismiss it. Quite often the lack of any such animals on Earth is used as an argument. Indeed, we do not have hog-sized starfish digging up the flower beds in our gardens, and personally I deplore the absence of elephantine centipedes. But before dismissing them it may pay to try to specify the reasons why there are no such animals. A first and simple reason why there are no big starfish walking around on Earth is evolutionary competition; their seat is already taken!

Another, and possible more important reason may be sought in a respiratory system. Some arthropods have tubes entering the body supplying each cell of the body with air for gas exchange. Beyond a certain size passive gas exchange in this way is simply unsuitable, so that limits growth. Our own respiratory system does of course allow large body size, possibly exactly because it does not attempt to reach every cell; instead, that task is relegated to the circulation. Altering an unsuitable respiratory system may need going back to the drawing board to start all over again, but evolution does not do that. It either adapts another organ, or tinkers with what there is instead.

Having an exoskeleton is another difficulty: for the same strength you need more material than for an endoskeleton, and growth is a major design problem. But this particular problem does lend itself to gradual change: if you simply strengthen one side of an exoskeletal tube and weaken the other side, you keep the weight-bearing function intact while sparing weight. Repeat this a few times, and you have a weight-bearing strut that does not envelop the limb. This is evolutionary tinkering, and this is how Furahan hexapods developed a practical skeleton. This also explains why dermal armour crops up so easily in hexapods; their skin, a secondary development, can easily revert to armour production. Luckily for them, protohexapods already had a nice pumping system in place pumping blood as well as air, so they did not have to solve too many problems at one. If Earth's arthropods had has another respiratory system, who knows what might have happened?

In the end, of course, all this remains speculation. And as we all read the same books and are subjected to the same sources, we come up with the same alien designs. I've called it 'speculatory convergence' or 'convergent speculation', a concept related rather closely to convergent evolution. Dougal developed secondary bilateral symmetry for brachiosyms as well as sulcosyms. I developed secondary bilateralism as well, but only for some predatory neospidrids. You will find an example here. Spidrids, of course, are radially symmetrical, but these neospidrids have a symmetry plane going through one leg, just like the brachiosyms. Convergent speculation...

Friday 22 January 2010

Speculative biology in Japan; help needed

Last March I asked whether anyone knew of any more sites showcasing speculative biology (here and here), and received a number of replies. Among them were Pavel Volkov who provided a list, and Josh who later alerted me to the Morae River project. What surprised me a bit was that the somewhat narrow geographical range of these projects. Most are American or British, with just a few others thrown in. Pavel is Russian, I am Dutch, but where are the others? Linguistic barriers might be to blame, but I have searched in some languages besides English, and hadn't found much. It may have to do with science fiction being less accepted in some cultures than others, or perhaps there are other explanations. The ability not to take yourself overly serious might be a prerequisite to spend vast amounts of time on an intellectual fantasy. I'm open to suggestions.

At any rate, I was puzzled by the absence of one country in particular: Japan. I know we did find one or two links to Japanese sites the last time, but there does not seem to be anything on a large scale. Dougal Dixon's book and projects like 'The Future is Wild' seem to go down well there; the thriving manga and anime culture also suggests that nothing stands in the way of a nice speculative biology project.

By the way, out of curiosity I just ordered a secondhand manga (comic) version of 'The Future is Wild'. Not that I can read Japanese, but I do not expect a comic about animals to be heavy on text. I will show bits of it here in due time, unless I find it too disappointing.

Back to the issue at hand. Luckily, there is a Japanese version of Amazon. It is partly in English, but with Google's translation services even the Japanese version makes some sense. I started by typing in 'Dougal Dixon', and then clicked the part of the page where it normally says something like 'here are similar books you might like'. If you do so, you will encounter books on 'The Future is Wild' as well as the Rhinogradentia. I found three books that looked intriguing. Their titles seem to have 'kimono' in them, but the illustrations on their covers suggest something altogether different.

Click to enlarge

Here they are. Have a look at the animal on the cover with the yellow design. We see a fish with a rather human-looking face, and will let that one pass. But behind it is what must be a flying snail. There isn't much I can tell about the others (one's a virus). Apparently these two books were published several years ago.

Click to enlarge

This one, I gather, bundles the other two. It's the fish again. So what are the books about? Somehow the fact that here is a text I cannot begin to understand adds an alien touch that rather fits the subject. Anyway, there were customer reviews, and here is what Google's translator program made of one of them:

"I have to muster Kimono - Graffiti The Unusual Biology (book (soft cover))

This book is "Kimono not Enough" "Enough and footwear also not" is omitted the bound volumes and some from column. (→ did not have these books the reader (me) this is advantageous to) a real strange creatures and 130 species Journal. Facing two strange creatures are a kind of introduction page. (Real-page black and white illustrations on the right (+ Omake occasionally) witty comments and a short description page on the left) you can pick up to read from anywhere. Look at the illustrations feel Idaki Kosobagayui (→ ...), but dreams do come to read the comments or grin, or wonder. It's not boring the reader is this. While reading "What appeared Kettai biological ecosystems do it?』 Or 『evolutionary theory to explain it I wonder?" It makes the question of nature and inspire. This year (2009) The 200 birth anniversary of Darwin's Origin of Species marks the 150 anniversary of publication, this book is suitable for one year I Memorial is such a book (laughs). This book is a serious book of biology, despite not promote reading as "a serious and』 or 『Let's theory of evolution-related reading a book" that "curiosity" and consequently Yo clock has a clock."

Right. Too bad Star Treks's universal translator is not quite ready yet. Still, most can be understood, and this indeed seems to be a work on speculative biology. The reviewer thinks it is serious biology, meaning he is probably like me or you. Some other sentences baffle me; 'Yo clock has a clock' sounds good though.

I know that this blog is occasionally read by people in Japan, so I am asking those readers for help! Are these books really about speculative biology? Are they good? Let us know!

Wednesday 13 January 2010

Anatomy of an alien IV: Sulfuria

Writing this a new post took a bit more time than usual, for which there are two reasons. The first is that quite often I simply run out of time. In fact, I have found that putting up a post almost every week (I did 50 in 2009) is about enough to stop me working on new content for the Furaha site. For that reason alone I may decide to slow down a bit.

The second reason is that I had lots of problems in trying to upload videos. The main reason was that I tried to do it with software I was unfamiliar with (Adobe Premiere Elements). I could make great titles with it, but the resulting file was about 850 Mb, whereas comparable earlier ones were less than 20 Mb. In the end I went back to the previous painful process involving three different programs and convoluted steps. There are too many video formats, and if you are not an expert life is hard.

Anyway, in the end I managed to upload a file. Today's post is once more about the BBC documentary 'Natural history of an alien', also known as 'Anatomy of an alien'. I rather prefer the first title. After that there will be only one fragment left to post on this blog, but this does not mean that the entire program will then have been posted here. Some parts deal with life on early Earth or on general biology, and I thought these would not be of major importance to the readership of this blog.

Both remaining sections feature the work of Dougal Dixon, someone who probably needs no introduction in the world of speculative biology. For those who do not know his work, he wrote several landmark books in the field, of which I like "After Man, a zoology of the future", and "The New Dinosaurs the best". In those years he and I communicated a few times by regular mail (yes, it was that long ago).

Click to enlarge; copyright BBC 1997

The present post is about the world 'Sulfuria', equiped with a very dense atmosphere. As discussed before, heavy atmospheres lend themselves well to flight, both of the 'heavier'and of the 'lighter-than-air' varieties. One of Sulfuria's major lifeforms is a 'ballont'; for previous discussions, see here, here and here. It is not a free floating one though, but a stalked one. The story is that these beings stick out above the clouds, where they are in the sun. Presumably sunlight is beneficial to them in the sense that it drives their biochemistry, but like many details in this programme the rationale for this is not spelled out.

The ballonts are rather nice, I think, but then again I have always been partials to ballonts. One small problem is that it is very difficult to get a sense of scale, if there is nothing in the image to compare the ballonts with. It would have been nice to learn a bit more about this biotope: there may be more flying forms, and some might be involved in the life cycle or ecology of he giant ballonts. I guess we will have to make these up ourselves.

The last fragment in this series will be posted in the near future, and will also deal with Dixon's work. In it, he discusses another invented world, called "Greenworld". I think I still have photocopies of sketches of Greenworld creatures he sent me years ago. Unfortunately, the work did not then see the light as a book, but I read recently that Greenworld is in fact about to be published, in Japanese. I will keep my eyes open for that one; not that I read Japanese, but I hope there will be pictures...

Sunday 3 January 2010

Anatomy of an alien III: Europan waters

The first blog entry in this new decade travels back in time again, to the 1997 BBC television series 'Anatomy of an alien'. This time the chosen fragment chosen deals with life on the moon Europa, or perhaps it may be better to call it 'in Europa', as the life forms in question are found in water underneath an ice cap over 15 km thick (according to the documentary).

You will first see an explanation of deep ocean vents on Earth, and those are never boring. Jack Cohen makes an appearance again, to speculate about similar vents in Europan seas or lakes. The vents are surrounded with walls built by bacteria that stretch upwards to form very long tubes. The speculation really gets underway when it deals with the ecosystem surrounding these tubes. There are creatures that can bite or drill through the wall of the tube, after which they gorge themselves on bacteria from within the tube. Of course there are predators out there too, preying on the 'grazers'.

Click to enlarge; copyright BBC

Here is a picture of a bacterivore; the predators have almost exactly the same shape. There is a feeding trunk on the front end of the animal, underneath the central opening. There is another opening in the front end of the animal; what is it for? Unfortunately, the documentary keeps completely silent about the body plan of these animals, which is a pity.

There is an opening right at the front, and one at the back. The one in the front is not for feeding. Perhaps these are the inlet and outlet openings of its respiratory system. After all, there is no reason to have air go in and out through the same opening, as is the case in Earth's tetrapods. Actually, using the same opening for air moving in and out is not good engineering, and is probably just a remnant of lungs starting as a sac with just one opening. In Earth's fish, waters enter the mouth and leave through its sides after having passed through the gills; a much better design! Obviously, evolution should be able to find other solutions on other worlds: air enters the lungs of Furahan hexapods through openings at the front of the trunk, and exits the body at its rear end (not that you can see that on any of the paintings on the site, but is true nevertheless).

Click to enlarge; copyright Gert van Dijk

Then again, the Europan bacteriovore's openings might have to do with propulsion, in which case these animals would have the same propulsion system as is found on Furaha. Just visit the page, choose the 'water' icon; choose 'swimming with...', and then got to the 'tubes' page. There you are. To save you the trouble I copied the image to this blog message; mind you, the image shows the external appearance of the animal; to understand how it works you still have to visit the page. I doubt that this propulsion system was separately invented for the Europan creatures. If so much thought would have gone into their design, you would think that this neat feature would be mentioned, and it isn't.

Still, there is something else about their propulsion that makes me wonder. The animals have a set of three fins around their body, more or less like the pectoral and back fins of sharks and dolphins. This makes sense, as three such fins are useful in countering rotations around the body's front-to-aft axis. You would want such fins near the centre of the body, as they would impede movements around the other axes if placed at the front or the rear of the animal. These animals indeed have three such wings right where you would expect them, around the centre of mass. As an aside, you may well wonder why there are three. To counter rotations, two or four (or more) would work just as well. Their area may have to increase if you have fewer fins, and vice versa, but that does not seem to be an important factor. Some whales have large dorsal fins and some have no dorsal fins at all, so having two seems to work as well as having three. Why are there never four? Is this just an evolutionary accident? Perhaps it is easier to have more such fins at the bottom half of the animal than at the top half, if only to make it easier to keep the body upright.

Anyway, now have a look at the tail of Europan bacterivores: there is another, smaller, set of three fins. That only makes sense if the animal needs more to be kept on track like an arrow, but this 'triad' fin design is not optimal if you use the tail for propulsion. Suppose you wish to beat the tail in an up and down direction: with a triad set the top fin will be useless for propulsion. While moving upwards it might even start to bend sideways and then it would impair propulsion. The other two will not be perpendicular to the direction of movement and will therefore not provide optimal thrust. No, if you want a beating tail, the surfaces providing propulsion must be perpendicular to the direction of the beat, and surfaces not aiding in propulsion should not be in the way.

Whale shark  / orca / orca; click to enlarge

The tails of sharks and whales provide excellent examples of this design. The pictures above were taken from the internet. The whale shark beats its tail sideways, and the 'stem' of the tail, just before the tail fin, is flattened sideways. In this way, there is room for the attachment of muscles and ligaments without impairing propulsion. The two photographs of orca's show that an orca's tail stem is flattened vertically, exactly as expected for an animal that beats its tail up and down.      
Back to Europan bacterivores. Their tails suggest a mode of propulsion similar or identical to the ones I invented for Furaha. Convergent speculation once again? Possibly; remember that this type of propulsion results in linear motion without any externally visible means of propulsion. That is not what you see in the video. Instead, the predators near the end can be seen to swim with a strongly undulatory pattern, like the one you would expect for animals with sideways-beating tails.

I wonder what happened to cause this odd combination of a design plan with a movement pattern that doesn't seem to fit the plan. The people who designed these animals knew what they were doing, so the answer probably does not lie there. Perhaps the animators simply added a familiar type of movement to add some spice to the footage? That is possible: I remember from conversations with Steven Hanly that the movement of Eponan uthers in the same documentary did not come out as planned either. I doubt we will ever know.