Small leaves and fast flowering are important adaptations for plants that live in cold temperatures and water-logged/frozen soils. plants exhibiting these traits are present in alpine biomes, but species are different, and found in different families, in the northern rocky mountains and the andes. what is the most likely explanation for this observation?

Convergent evolution

Explanation:

The question above shows a case of convergent evolution.

Convergent evolution is a process that allows similar characteristics to emerge in two species that are not directly related, that is, that do not have a common ancestor that allows genetic similarities to justify this characteristic in common. These characteristics are even called analogous structures. It is common for this type of evolution to occur through natural selection because the selective pressure of an environment allows adapted characteristics to remain in a species.

answer; i believe the answer is hydraulic action;

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.