# How would lifeforms adapt to a planet with compressional features? [closed]

I'm working on a story about how humans visit and start inhabiting an alien world in Messier 10 that contracted as its core cooled, not quite unlike Mercury. So I was wondering what the effects of the compression would be on the lifeforms of the planet. How would lifeforms adapt to a planet where there are cliffs up to two kilometers high and hundreds of kilometers long? Where could lifeforms on this planet inhabit? My ideas so far:

• There is a high enough atmospheric pressure for lifeforms to only live on the edges of the cliffs (scarps)

• The cliffs cut off the environments and there are several zones that evolve seperately (cool idea)

• The animals could adapt to survive a range of different atmospheric pressures, so that they could survive at a range of altitudes

• Please limit your question to one problem. Split them in more linked questions for better clarity. As it is now your question is too broad.
– L.Dutch
Jul 13, 2017 at 11:40
• Welcome to Worldbuilding SE, JavaScriptCoder, I am puzzled. if the planet contracted as it cooled, wouldn't it have been too hot for life in the first place? Also, compression implies external forces making it contract. Gravity is a possibility, but it would have to be very strong to do so. Sorry to ask, but I'm trying to wrap my head the mechanism involved. Jul 13, 2017 at 12:07
• We have tectonics now, but there are regions of plate creation and destruction. So you're asking what geological forces are in play with purely compression plates? Jul 13, 2017 at 12:15
• Java it's unclear what you mean by "compression". (Were you thinking of kind of like a neutron star or black hole ??) Jul 13, 2017 at 13:45
• Mercury is an example of a planet that underwent compression. According to Wikipedia as Mercury's interior cooled, it contracted and its surface began to deform, creating wrinkle ridges and lobate scarps associated with thrust faults. The scarps can reach lengths of 1000 km and heights of 3 km. Jul 14, 2017 at 17:35