Celestia Forums

Some days ago I had a very great idea: Sulphur-based life.
The animals and plants of this planet live in temperatures around 423K and 466K. The atmosphere have sulphur and methane in abundance and some water vapor. The atmosphere is more dense than the Earth. The color of the planet is yellow with green florests. They breathe sulphur gas instead of oxigen and instead of water they live in a liquid substance that have sulphur.
They breathe sulphur gas because of the temperature and because of the fast quimic reactions using sulphur. They need to obtain more energy to their cells using sulphur instead of oxigen. The complex proteins of these beings are adapted to the high temperatures and use sulphur with extreme caution.
Our proteins also use oxigen with extreme caution because oxigen is very corrosive and reactive.
The animals have a high resistant skin. The skin look like of the crocodile, but is more thin. The skin serve to protect them from extreme temperatures and high radiations, like ultraviolet, X-rays and radioactive elements. Also, the skin protect them against other animals, because these animals mark territories that have enough food for them. The skeleton is cartilagenous and high resistant, is not made of calcium, and this help them from X-rays.

Any suggestions or commentaries are welcome.

The substance is H2S and is similar to water, but instead oxigen have sulphur. I am making a system with this moon. This moon orbit around a small gas giant that have clouds like on Venus. The proteins of the beings are made of carbon, nitrogen compounds and a big abundance of metals.

I think beings cannot depend tottaly on ammonia because ammonia have much limitations in comparision to water to form life. Before, I thought it would possible life to form in ammonia but now I don't agree with ammonia-based life because of the very low metabolism and the quimic reactions.

But I think that is possible life to form in sulphur-based subastances because of the high metabolism and because sulphur is in the same family of the oxigen in the Periodic Table.

Sulphur-based substances tends to be liquid in temperatures above 373K, and I think these substances tends to be more dense than water.

These creatures of this planet are all herbivorous and don't exist carnivorous on this planet, because all animals depend directly on plants.
What do you think of all these ideas?

I don't know if you need to limit the animals of this biosphere to a herbivous life style;

on our own planet there are many microscopic predators, eating other micro-organisms and other organic detritus; so it is natural to expect the development of large scale predators as well.
I wouldn't expect there to be any barrier to the development of large predators on your sulphur planet, but if you have a reason in mind, I would be interested in it.

Certainly it takes a lot more energy to be a predator than a herbivore; but the rewards are generally greater.

They are all herbivorous because the sulphur and other chemicals based on sulphur and high temperatures give to them all energy and the nutrients they need to spend by many hours per day. The desert areas are small and the majority part of the surface have dense jungles with sufficient quantities of plants they need. If the temperature of the planet decrase or increase, and if have any catastrofic moments on such planet, they will need to eat other animals, but for lucky this planet NEVER had any catastrofic moments and the planet always had dense jungles to feed them. Not only in the surface, but also in oceans.

Actually reaonably catastphophic moments are probably essential to get evolutionary diversity;
if you have a stable, unchanging environment I expect you would get a very low diversity in the lifeforms of your world.

But if the lifeforms can survive with a low diversity and little change in their environment then you would have a biosphere quite unlike that of Earth.

Interesting stuff.

Enio...

Keep it up....we need more extrasolar thinking like this.

eburacum...

can you give me a few more cents about why "disruption" is needed for diversification?

I'm focusing on propulsion now:

http://www.cloudynights.com/ubbthreads/ ... Post201688

But am glad to see there's a Physics and Astronomy sub-cat here.

Regards,
-Mike

mvg,

One way to look at it is that you have to survive in order for there to be future generations.

If their genes (or equivalent) are stable and there's nothing to cause certain physical types to die before they reproduce, then they'll continue to exist for many generations. When conditions become extreme, and assuming that their inherent genetic diversity is large enough, then only a small fraction of a species will reproduce successfully -- the ones that find it easiest to survive the new conditions. This can result in significant changes in physical characteristics in just a few generations.

Of course, there are many different conditions that affect viability. Subtle things like what individuals of the opposite sex find attractive can have profound effects.

selden wrote:Subtle things like what individuals of the opposite sex find attractive can have profound effects.

Yeah, tell me about it ...

Grant

granthutchison wrote:

selden wrote:Subtle things like what individuals of the opposite sex find attractive can have profound effects.

Yeah, tell me about it ...

Grant

ROFL !

well put, selden....thank you.

"Of course, there are many different conditions that affect viability. Subtle things like what individuals of the opposite sex find attractive can have profound effects."

all the more reason for (s)exploration...

-Mike

As far as disruption leading to diversity;
when the climate changes then biomes need to migrate across the surface of a hypothetical planet; the migration of individual species is sometimes (often) blocked by physical features like seas or mountains;

in this way a species might get isolated in a small area unable to migrate around unsuitable terrain- evolution can happen rapidly in such pockets.

Alternately a mass extinction caused by a single catastrophe can clear the land of long established species allowing new organisms to evolve into the vacant niches...
generally the diversity of the total population of organisms increases after such an event;
catastrophes can work the other way too- by decreasing the gene pool in a 'bottleneck effect', so a previously diverse species can become homogenous.

In fact according to the late Stephen Jay Gould, the total diversity of our ever changing world stays pretty even over time; but in a world with no 'disruption', and with a limited number of differing habitats, it may be that the population becomes homogenous and stays that way.

Eburacum wrote: in this way a species might get isolated in a small area unable to migrate around unsuitable terrain- evolution can happen rapidly in such pockets.

David Quammen's jaw-droppingly informative The Song of the Dodo: Island Biogeography in an Age of Extinction will pleasantly fill your head on this topic.
Grant

Looks like an interesting book; thanks.
You see, this is what worries me most about global warming, however caused; the biomes are cut up into tiny pieces by new obstacles- agriculture, roads, canals, cities;

the sea level rise we anticipate of a few metres in the next century or so is small compared to sea level changes between glacial and interglacial periods;
but in those days the world as not covered in a rigid network of anthropogenic obstacles; which cut up biomes and prevent migration and destroy diversity within their borders.

Oh, and people will find it difficult to migrate too- the coastal regions of the world are heavily populated, and represent a lot of economic value as well;
lose this and there will be millions more refugees and loss of trillions of dollars to the economy.

Forget The Day after Tomorrow and its ice; this is the real problem.

oops- off topic a bit- sorry...