When there is limited food.
There are really no steps in natural selection - just conditions required for it to occur.
What population? Perhaps you mean if there were no variation for natural selection to select from.
Without genetic diversity, natural selection cannot occur
Genetic variation. If there were no variation in the genes/phenotype then natural selection would have nothing to select from.
Everything from available food to climate will cause the changes we see in natural selection. Random mutations occur constantly and when those mutations are beneficial for life, the genetic code is more likely to be passed on to future generations.
There are really no steps in natural selection - just conditions required for it to occur.
What population? Perhaps you mean if there were no variation for natural selection to select from.
Without genetic diversity, natural selection cannot occur
the presence of predators
Natural selection may not occur in a population if there is no variation in traits among individuals, if all traits are selectively neutral, or if the environment is stable and consistently favors all individuals equally. Additionally, if all individuals are equally successful in reproducing and passing on their genes, natural selection may not be operating in that population.
no there is no genetic variation for natural selection to act upon
Natural selection
Genetic variation is necessary for natural selection to occur. This variation provides the raw material for differential survival and reproduction, which drives the process of natural selection. Without genetic variation, there would be no differences for natural selection to act upon.
Genetic variation. If there were no variation in the genes/phenotype then natural selection would have nothing to select from.
genetic drift, mutation, natural selection, and migration
Artificial selection tends to occur more quickly than natural selection because it involves intentional breeding by humans to promote desired traits in organisms. This focused approach can lead to rapid changes in specific characteristics over a few generations. In contrast, natural selection operates through environmental pressures and can take much longer for significant changes to occur, as it relies on random genetic variations and survival advantages over time.
Natural selection requires variation in traits within a population, heritability of those traits, and differential reproductive success based on those traits. Without these components, natural selection cannot act on a population.