I thoink it should be possible to create a creature that can float using essentially lighter-than-air-gas filled lungs. They would need some sort of organ system that allows them to produce or concentrate this gas. I think the easiest way to implement this would either be to have a creature that can heat up the air inside its “lungs” enough to float, or be able to produce methane or smth like it and fill their lungs with that. This would not be possible (or at least it hasn’t happened) on earth, possibly because our atmosphere is not dense enough, so maybe in the world settings we could have the ability to change atmosphere density/gas concentrations or something. Also here’s some really good blog posts someone made about the physics and speculative evolution of this concept gasbags Archives - Exocosm
I believe that’d be a nonlawk feature since we don’t see it irl
Gasbag would be great! Many people here has discussed them, too.
I recall hydrogen bladders are the more usual descriptors of gasbags in the forum discussions since hydrogen is even lighter than methane
The biggest problem with your suggestion, which I must thank ahh3415 for bringing to my attention, is how does such an organism get their Phosphorus and Sulfur. The six most critical elements of LAWK are: Carbon, Oxygen, Nitrogen, Hydrogen, Sulfur, and Phosphorus,. The first four are plentiful in the atmosphere. Situationally, Sulfur can be found in the atmosphere as well, but whether or not their would be enough for life is debatable/might vary. As far as I know, Phosphorus is not found in the atmosphere at all, and their is no organ (or organelle) for making it IRL, making that the biggest problem to be solved for floating lifeforms.
Perhaps if a floater organism shuttles between the sky and an ocean, it could still get those nutrients. Or be a tethered floater organism, with its base/roots in the ground to absorb Phosphorus, Ammonia, and Sulfur.
That can be made.
Could work, but that also limits how far it can go. A tethered organism would certainly not reach the Stratosphere, for example.
The problem with that is, if we are talking about a simple creature like a plant, what conditions would trigger how it reacted. For example, a flytrap has sensors on its leaves, and automatically closes them when it feels so much movement. It does not know what is their, and it is not a “choice”, it is an instinctual reaction to certain stimuli. How would a floating creature with a simple mind determine there is ocean beneath it and not something else? A more complex creature could probably pull that off, but I think this would be more work/steps to evolve later on, and thus would be less likely.
What if an organisms becomes a floater for only a portion of its life, such as only for reproduction/dispersal in the Stratosphere?
There is an example of a lifestage on earth that does not eat, where Atlas Moths do not eat anything after undergoing metamorphosis.
That is actually really interesting. I have not heard of Aeroplankton before. I have been trying to figure out how vegetation could support other things up there, and that makes it seem more plausible.
That might also work.
If there is enough vegetation/plankton floating up there, I am sure an ecosystem would eventually emerge. But few things could get everything they need up there, so lifestages of floating and not floating (perhaps in repeating cycles like some jellyfish) or an abundance of floating plankton would likely be needed to maintain an ecosystem.
If dense enough I presume floating vegetation could starve the plants beneath, in the water or on the ground, to death?
It’s definitely something I would love to have, though as said by others, probably as a non-LAWK option. It could be evoutionarily derived from swim bladders, digestive system or those pneumatophores from Man-o’-wars.
Indeed you have the main problem in my opinion, at the very least for the phosphorus. Like you said, there might be allowances for sulfur, but on the other hand there are probably trace amounts of other elements needed.
I’m going to speak of phosphorus since it’s simulated in Thrive, but you can include anything “not present as a gas in the atmosphere”. Now you can change physiology to use it as little as possible, but biological life that we know will always need some. So as for how to get it, I can see three main options:
- Don’t float all the time, come down to grab some now and then.
- Collecting atmospheric dust. (Saharan dust is a major source of phosphorus for the Amazon!)
- Getting it from other lifeforms. The carnivorous plant solution would be a very equivalent situation. But perhaps it would even be possible to have a mutualistic exchange of sugars for terrestrial dirt?
Considering the resource constraints, I doubt the floating vegetation could get dense enough? Maybe the tethered type, but now you’re just having balloon trees.
Also don’t plants need lots of magnesium to get their chloroplasts running? Would same mineral requirements for photosynthesis be in Thrive?
Very unlikely, we don’t represent thing to this level of detail in Thrive. It would be too much. We can use phosphorus to represent all the elements of this type.
Question, how would such a symbiosis come to be? Would they first be using one of the two other methods and only then switch to such mutualism?