i bet there are layercake lifeforms on heavier bodies.
maybe not our gas giants, in sol system (or maybe).
field lifeforms, and even entire contiguous global surface.
ones with boundaries could have evolutionary competing edges. between a transitional layer, where transitional layers are still clear matter phase changes (e.g. solid ground meets gas atmosphere).
jumping would be all but out of the question. vertical transport or movement of any form would be intensely more expensive under the great gravity.
tho then also, accomplishing such, would confer significant advantage, over all the other competing life and environmental stressors. so while we might consider the flat layer lifeforms the earlier life on a planet, like earth's billion or two years with mostly just single celled simple life. the available chemistry, if ample carbon, which is likely, may indeed form not disimilarly to dna like our own... maybe even so similar as to be in range of some intricate sub-genetic engineering. or it may be so radically different that it may even verge outside our conceptions of life... perhaps, for one example loosely tied to something we can see, it may be more like prions, but more advanced, and capable of more advanced behaviours than we see prions do, replicating, forming connections and more complex structures. and so it's at these earlier chemistry levels i wonder about the gravity effects and evolutionary selections. the cost benefits, sure, but who could imagine what could transpire in the trillions upon trillions of potential, that transpire over the eons of a huge planet evolving life over millions and billions of years.
even to extend that, leap ahead, past whether or not such life formed cells with nuclei and walls like our, to whether it forms emergent inteligencies... how many layers must a system have before complexities capable of self awareness, advanced creative reasoning, compassion, humour, memory and wisdom etc? we might look at our own computers, and begin to realise... not much. our biology did it because, no great expense not to go complex 3d in our neurostructures... but for a lifeform in a heavier gravity well with more pressure, getting up and jigging around all fat and wide and tall, is not so readily on the cards for their evolutionary easy grab potentials. but they could still be super duper intelligent and fun.
i mentioned a lifeform that's contiguous around an entire planet... but what if there's more than one. multiple layered. different chemsitry n pressures at each layer giving slightly, or significantly, different lifeforms evolved. some of the chemsitry actions may even cause transitional streams between layers. i've been imagining/depicting very flat, and even vertically static lifeforms. perhaps more dynamic ecosystems of transmuting chemicals between layers... one layer gasses as part of its process, and a layer above rains.
recently hearing ganymede's suspected to be heavily layered, i suspected has subconsciously in part inspired these thoughts. maybe there's life in #ganymede's
rocks. how evolved....? how like any of the life i've been imagining and sorta depicting some of? enough we could teach it to play tetris? no, sorry, that's silly. ;D we should come up with something wiser to share with our "alien" neighbours when we meet them. ;)