How would a jungle planet work?

[Myriad]

A cubic planet could have all the faces more or less at the same angle to the sun. So you could have six faces all equally temperate, or four tropical and two polar, or various combinations in between.

The problem is, all the water would run to the center of the faces. And all the air. (Oceans would form domes over the centers of faces -- however, their shorelines would not be round and their surfaces would not be spherical, because the gravity of a cube is complicated, and doesn't always attract directly toward the center.)

So, all the habitable zones could be jungle, but it would be jungle surrounded by very high mountains that extend way above the atmosphere.

Respectfully,
Myriad

 

[Earthborn]

It used to be that science semi-seriously suggested that Venus could be a jungle planet, but those scientists who figured it would be too hot were right. Still a Venus-planet is a good model for how such a planet might work. It's slow rotation around its axis and its thick CO₂ rich atmosphere make the surface temperature fairly constant from day to night and from the poles to the equator. The atmosphere would also need to be rich in water vapour. Many plants in rain forests take get their water directly from the air, but of course having rain would help.

The biggest problem with a jungle planet that I see is that a jungle is highly resource intensive. It drains the ground of all its nutrients and can only continue to exist if it occasionally gets new sediment from places that are not jungle. Here too can Venus provide a solution: the planet may have very active volcanism without plate tectonics periodically resurfacing large parts of the planet and thereby providing new mineral rich volcanic soil.

 

[Correa Neto]

As many posters wrote, a "single environment" world is not very likely - unless its a dead world, of course. If its about an Earth-like world, looking back in time to our own planet is a good idea.

Yes, it may or may not be required a slightly hotter temperature; there are temperate and equatorial rainforests. The key may be rainfall; it must be high.

High rainfall requires high humidity, so oceans are needed as a water source. Large continents (Pangea and Gondwana-style) tended to have an arid interior (IIRC what I read about Gondwana' s paleogeography). The air looses humidity before reaching its inner areas. Large mountain ranges surrounding the shorelines will also be bad for jungles, since they will block winds coming from the oceans.

I would design this world as composed by small land masses, no big continents. Australia maybe would be too big. Picture it as having no single land mass bigger than New Zealand; imagine however a world with several island arcs as Japan, Sumatra and Indonesia, Hawaii-like island chains and scattered oceanic islands. So yes, it would have plate tectonics. And yes, its past (and future) would have different climatic patterns. Tides would depend on the presence, size and distance of one or more moons. This ocean-dominated world would probably have some fierce storms.

 

[Tero]

A cubic planet could have all the faces more or less at the same angle to the sun. So you could have six faces all equally temperate, or four tropical and two polar, or various combinations in between.

The problem is, all the water would run to the center of the faces. And all the air. (Oceans would form domes over the centers of faces -- however, their shorelines would not be round and their surfaces would not be spherical, because the gravity of a cube is complicated, and doesn't always attract directly toward the center.)

So, all the habitable zones could be jungle, but it would be jungle surrounded by very high mountains that extend way above the atmosphere.

Respectfully,
Myriad

How big your planet be? If it was all solid, maybe.

 

[dasmiller]

I would design this world as composed by small land masses, no big continents. Australia maybe would be too big.

Actually, I'd say that our Australia is an existence proof for your theory that Australia is too big. I haven't actually visited Australia, but I have it on good authority (Google Earth) that Australia's interior is *not* covered with jungle despite the fact that Australia is on a planet whose surface is 70% water and that there are known jungles at the same latitudes as Australia.

 

[dafydd]

The planet Tarzan.

 

[Comrade Raptor]

This reminds me of an argument I had a long, long time ago about whether Star Wars counted as science fiction.

The Empire Strikes Back (with science)

All the rebels suffocate on Hoth. Empire wins. Roll credits.

 

[Toke]

Come on, the ice algae handle the oxygen balance in the atmosphere.

The inert gas plants on supply vessels are made with a filter to seperate nitrogen from oxygen. It would not be too far out sci-fi to claim the existance of CO2 filter masks that would let one live on a jungle planet with a high percentage of CO2 in the atmosphere.

 

[Mudcat]

What's amusing to me is how much a friend of mine makes an issue that alien life is too similar to Earth in science fiction, and he used this point to make the exact opposite case to yours.

This seems to be common complaint of fans and critiques of sci-fi/fantasy and one I find highly annoying. My view is that if there's a successful design you see a lot of on one planet (weather that design is natural or influenced is beside the point completely) than you can expect to see that design repeated.

So in real life you should expect lifeforms that look familiar (if somewhat divergent) on Earth.

 

[Ziggurat]

Edit: I was willing to suspend disbelief on the similarity of Naavi to humans as a necessary part of making an entertaining movie.

It wasn't necessary at all to make the movie entertaining. What it was necessary for was so that the audience sympathized with a character being sexually attracted to them. Which Cameron needed to do because all he's really got in his narrative bag is cheap tricks and cliches. A better writer could have pulled off an entertaining movie without depending on sexual attraction to motivate characters and win over the audience. Cameron doesn't have the chops to pull something like that off, but that doesn't mean nobody does.

 

[Dinwar]

My view is that if there's a successful design you see a lot of on one planet (weather that design is natural or influenced is beside the point completely) than you can expect to see that design repeated.

If there were multiple, competing life forms and styles, I'd agree. However, as all life on Earth arose from one common ancestral species, you can't really use Earth to determine what life in general is like--you're essentially extrapolating from a single datapoint. And since we don't even have a decent definition of "life", that makes it far more silly.

So in real life you should expect lifeforms that look familiar (if somewhat divergent) on Earth.

Which ones? The most common life form on Earth is single-celled Bacteria and Archea. In fact, a very good argument can be made that ALL Earth life is bacteria/Archea, some just are colonial. And why stick with cells as the building blocks of an organism? I know of colonial organisms (bryozoans, mostly) in which the individual organisms act as cells do in our bodies--different polips specialize in digestion, or reproduction, or in a few cases locomotion (one of the weirdest things I've ever seen--a bryozoan colony walking across the sea floor). Phylum Arthropoda has more diversity that any fifty sci-fi books put together. And all of this is going off of what's alive today. When you look at the past, it gets much, much weirder.

Sci-fi authors really have little imagination, in my experience. They pick a few species that they like, tweek them slightly, and call them aliens (monkeys become Wookies, beetles become Buggers, wolves become Bothans, humans become Romulans, Klingons, Volcans, and the rest, earthworms become Sha-Halud...).

Unfortunately, we're doing that ourselves, in this thread. I'll grant that it's a fundamental assumption of the thread that we're dealing with Earth-like life, but there's no reason to assume it's so. I mean, what IS a forest? From an animal's perspective it's an area dominated by large, woody plants--but that puts an entire kingdom into the background. From a plant's perspective, it's more akin to Normandy Beach, circa D-Day. They use chemical warfare, germ warfare, invading armies (insects), and even quite literally strangle one another. From a plant's perspective, the only difference between a forest and a human war zone is that humans are faster. And it makes perfect sense for the forest to be a war zone. Resources are INCREDIBLY scarce; most of what's there is in the biosphere, so there's little left for new growth.

So really, a forest is a slow war fought over resources and fought by predominantly stationary entities. It's not too hard to imagine something like that happening without plants.

And the division between "plant" and "animal" is entirely an artifact of our history. It's equally concievable that another planet doesn't have such a distinction--organisms on that planet may be mobile and photosynthetic. It's not that weird: in oceans, most photosynthetic critters are mobile, while most hetertrophes are sessile. Could be that this trait carries onto land on another planet. In which case a forest would be mobile, and most likely migratory, moving south for the winter. Just don't try to cut the "plants" down for fire wood--they'd be able to fight back.

Large continents (Pangea and Gondwana-style) tended to have an arid interior (IIRC what I read about Gondwana' s paleogeography).

You remember correctly, sir. Large land masses have another effect as well: they limit the amount of shallow marine ecosystem. Which means limiting the amount of biomass you can have (deep oceans don't have much, and arid continents can't support much). They also muck with ocean currents, meaning that you may get more or less upwelling (and therefore more or less in the way of phytoplankton), which likely has an affect on the amount of biomass.

 

[Denver]

Maybe a planet and a sun that would generate jungle-temperatures pole to pole, except existing in a field of ice comets and meteors that are, at some interval, smashing into the poles. That might allow a tension in the otherwise flat temperature profile, creating weather conditions conducive to a thriving jungle on most of the surface.

I read one with the concept of "Stories" in the jungle, humans lived in a specific type on "home" tree with their symbiotic "bears"
Traveling too many stories up or down got them into very dangerous territory.

Yeah I think that was Midworld.

 

[Correa Neto]

Actually, I'd say that our Australia is an existence proof for your theory that Australia is too big. I haven't actually visited Australia, but I have it on good authority (Google Earth) that Australia's interior is *not* covered with jungle despite the fact that Australia is on a planet whose surface is 70% water and that there are known jungles at the same latitudes as Australia.

Yes, I was being perhaps a little bit too cautious. But there's a reason for this, hinted at this section of Dinwar's post:

You remember correctly, sir. Large land masses have another effect as well: they limit the amount of shallow marine ecosystem. Which means limiting the amount of biomass you can have (deep oceans don't have much, and arid continents can't support much). They also muck with ocean currents, meaning that you may get more or less upwelling (and therefore more or less in the way of phytoplankton), which likely has an affect on the amount of biomass.

Continent, from a geologist's POV, does not necessarily mean exposed land. In the past, continents (even Gondwana) had shallow internal seas. It all depends on global sea level. A shallow inner sea over an alien Australia-sized continent could become an incredibly productive environment, since a large portion of the sea bed would receive sunlight. Sure, this assuming an Earth-like biota and a constant influx of water (oceanic, rainfall, rivers) to ballance evaporation, thus avoiding it to become a large version of the Dead Sea. Picture an inner shallow sea with the equivalent of Australia's barrier reef. Reefs, lagoons, bays, underwater forests of algae or adapted plants. Islands around and within this sea could be covered with jungles and surrounded by mangroves. Sure, as soon as global sea level drop below a certain point, chances are a desert will develop where the sea was located.

 

[MontagK505]

This seems to be common complaint of fans and critiques of sci-fi/fantasy and one I find highly annoying. My view is that if there's a successful design you see a lot of on one planet (weather that design is natural or influenced is beside the point completely) than you can expect to see that design repeated.

So in real life you should expect lifeforms that look familiar (if somewhat divergent) on Earth.

Interesting enough, the stereoscopic vision that served our arboreal predecessors is also useful for hunting and making precision tools, along with fine motor control in our hands.

That's why humanoid aliens in an earth like environment are not that unlikely. The main sensory platform has to be near to the central nervous system. Too long a time delay between eye/ear and brain could get you killed. Three eyes might give you greater visual acuity but the advantage could be offset because it would tie up too much processor power in the brain. Dolphins have a similar problem in that much of their brain power is used for processing audio information.

 

[Halfcentaur]

This seems to be common complaint of fans and critiques of sci-fi/fantasy and one I find highly annoying. My view is that if there's a successful design you see a lot of on one planet (weather that design is natural or influenced is beside the point completely) than you can expect to see that design repeated.

So in real life you should expect lifeforms that look familiar (if somewhat divergent) on Earth.

Exactly, niches and what not. I love really far out alien concepts, but people don't factor in how things like binocular vision and limbs and wings are something you'd expect to see repeated in a universe that has a process like natural selection at work.

 

[Dinwar]

Continent, from a geologist's POV, does not necessarily mean exposed land. In the past, continents (even Gondwana) had shallow internal seas. It all depends on global sea level.

My point was that when you have all the continents together in one or two large land masses, simple geometry dictates that you can't have as much shallow marine areas--unless, I suppose, you put them under so much water that all but mountain ranges are submerged. And even then, you tend to have less heterogeneity, because the majority of your shallow areas are connected (it's easier for a lobster to walk from Main to Florida than from Main to England, so we get Homaris americanus in America and H. gamarus in Europe, that kind of thing).

Sure, as soon as global sea level drop below a certain point, chances are a desert will develop where the sea was located.

If the Basin and Range Province is any indication, sea level won't be the major factor here: regional rainfall will. They're usually, but not always, linked--the Salton Sea, for example, is controlled by geomorphology, and how high the lake gets is a function of where the Colorado travels. There are other lakes too, I just forget which ones off hand (done a fair bit on the Salton Sea recently, so it's pretty fresh in my mind). But your point is well taken: a large number of shallow seas can have major climatic impacts, including huge increases in desert life. Not sure I agree with how MUCH of an increase (ie, I doubt, given the paleobotony of the Basin and Range Province, that we'd get global jungles that way), but there's certainly a major impact.

That's why humanoid aliens in an earth like environment are not that unlikely.

Depends on what you call humanoid. If you mean a bipedal terrestrial omnivore that uses tools and has a general human limb configuration, it's very, very unlikely, particularly the "general human limb configuration" part. In our own planet's 4.8 billion year history, only apes and monkeys are even vaguely humanoid (I'm including all human species and their relatives with apes; going by the official taxonomy, in other words). That means that humanoid species have been here less than 20 million years. True humanoids--things you'd look at and go "Oh, that looks sorta like a human" have been around about 5 million years. On our own planet we are an INCREDIBLY rare event.

As for the rest....Yes, a cephalized organism (those with sensory organs predominantly located in the head--ie, those with heads) is almost certain on any other planet with complex (multicellular and non-colonial) life. But bear in mind that lobsters, fish, birds, beetles, flatworms, roundworms, hookworms, gastropods, cephalopods, etc. are all cephalized. None of them are anywhere close to humanoid. And again, I'm only going with living things--get into the Early Cambrian and you'll see cephalized organisms that are well beyond anything science fiction has come up with (a few that Dr. Seuse would say "Okay, now that's just too far").

I love really far out alien concepts, but people don't factor in how things like binocular vision and limbs and wings are something you'd expect to see repeated in a universe that has a process like natural selection at work.

The reason most land vertebrates have four limbs isn't because there's some advantage to it--the fish that we evolved from just happened to have four limbs. Similarly, there's no real advantage to having five fingers--our ancestors just happened to have five, and we haven't lost any. And remember, land vertebrates are a very tiny fraction of the animals out there. As for niches, most niches are created by other life forms. A woodpecker only has a niche because there are stationary trees that don't whomp them. Grazers exist because grass is sessile. While certain configurations would certainly be universal (again, cephalization; I'd probably include segmentation in this, as well as possessing some skeleton), I think those universals would be fairly limited, and fairly general. I mean, a race of centors is entirely plausible--all it would take is for the fish that crawled out to have six fins, rather than four. Monkeys with two tails are plausible. Four-winged birds actually existed. Mobile colonies in which each organism is highly specialized exist.

Life, in other words, is far more weird and wonderful than people generally think, and a sci-fi writer could blow people's minds just by showing what's already alive today. Alien worlds should be at LEAST as weird as what we share our biosphere with.

 

[Andrew Wiggin]

You just tell the matte painters you need a jungle planet background for the next scene. Or you have ILM do it in digital postproduction.

 

[Roboramma]

It wasn't necessary at all to make the movie entertaining. What it was necessary for was so that the audience sympathized with a character being sexually attracted to them. Which Cameron needed to do because all he's really got in his narrative bag is cheap tricks and cliches. A better writer could have pulled off an entertaining movie without depending on sexual attraction to motivate characters and win over the audience. Cameron doesn't have the chops to pull something like that off, but that doesn't mean nobody does.

Point taken and conceded, it would have been a different movie, but I'll admit could have been done well, and if done well would have been a much better movie than the one we saw.

I can't watch youtube videos in china, though, what was that of?

 

[Andrew Wiggin]

Point taken and conceded, it would have been a different movie, but I'll admit could have been done well, and if done well would have been a much better movie than the one we saw.

I can't watch youtube videos in china, though, what was that of?

A very amusing and cruel review that deconstructed AVATAR. Worth watching. Too bad you can't see it.

 

[Beelzebuddy]

Had the Naavi looked like giant bugs, communication with the fictional humans would have been even less mutually informative than in the movie and the audience would have been right behind the Colonel. Trudi and the rest would look like traitors.