Evolutionary pressure, or selective pressure, can be considered the pressure exerted by external forces on the evolutionary process of an organism, thereby altering the direction of this process. The so-called "survival of the fittest in natural selection" means that nature exerts selective pressure on organisms, allowing those who adapt to the natural environment to survive and reproduce.
Selective pressure is precisely one of the driving forces of evolution.
Yawgmoth grinned: "This question isn't that difficult, after all. Evolutionary pressure, besides changes in climate and environment, mostly comes from other species or other individuals within the same population. The enemies, prey, other species within the same ecological niche, and every individual competing for mating rights within a population are all sources of evolutionary pressure. Much of evolution comes from 'competition between species.'
