Explain how natural selection can lead to evolution?

Answer 1

Natural selection works on a simple premise that the better equipped have more chance of survival and reproduction. The fact that the 'better' animal has more chance of producing offspring means more of his or her genes reach the next generation than his or her weaker rivals, thus weakness is filtered out. Although luck and chance can come into the equation (a 'weaker' animal may get lucky) in the long run over generations and generations, luck is no match for 'good' genes which enable advantages in the fight for survival. The chemical process of reproduction is slightly different. When cells are creating copies of themselves to make the new being, they are essentially copying enormous sets of instructions that their parents cells followed to create them, and the offsprings cells will use to build them. As the instructions are so huge, the number of cells involved is so colossal, the number of animals involved in reproducing is vast, and the number of generations and generations, and millions and millions of years… the opportunity for 'mistakes' is likewise gigantic, no matter how accurate and efficient the cells involved are supposed to be. These 'chance' mistakes are actually something like 1 in a giga-mega-godzillion (not an official statistical measure I might add!) but because the process happens more than a giga-mega-godzillion times, mutations are seen to occur. These mutations can either improve the animal slightly, or hinder it. The mutations are never that huge as the new being would be unable to survive or find a mate if it drastically differed from the species as a whole. Of course, any improved instructions which give the being a slight advantage, have more chances of being copied in the future - the mutation is now the new standard. An interesting position on this is that cells actually evolved with this chance of mutation. Cells which were 100% accurate in their reproductive instruction copying never hit upon anything new, or advantageous to the species while the world changed around them. What was a good design then, perhaps isn't so good in today's world. Meanwhile, cells which had a 99.999999…..% accuracy were actually more successful in the fight for survival as they enabled the opportunity for mutation, and thus the opportunity for improvement - a species which can change with time is far more likely to survive in a world that too changes with time. With this in mind, you could argue randomness in cell mutation was actually naturally selected by a non-random process!

Answer 2

Natural selection acts on the genetic diversity of a population, where the best traits for survival and reproduction increase in frequency over time. Since natural selection pushes a population's traits in an advantageous direction, it's not random but rather predictable, since we know its purpose.

Answer 3

Individuals in a population differ from each other. Some individuals will have characteristics that make them well adapted to their environment whereas others will have characteristics that make them less adapted to their environment. The better adapted individuals are the ones that are more likely to survive and produce offspring while the less adapted ones are more likely to die. This is called natural selection. Natural selection results in the better adapted individuals to pass on their characteristics to more offspring as the lesser adapted ones are more likely to die before they reproduce. Over time, this result accumulates and a new generation is created with the favourable characteristics that makes this species better adapted to its environment. Natural selection has lead to the species evolving.

Answer 4

Natural selection is when favorable traits are passed down to offspring while harmful and less favorable traits are eliminated, due to higher predation, competition from the organisms with more favored traits, etc. Since organisms with more favored traits will, logically, have much more chance of surviving to reproduce than those who lack the favored traits, the next generations will slowly start to accumulate a higher percentage of organisms who have the favored traits. This is quite the opposite of random, as traits that help the organism survive will obviously be more likely to stay in the gene pool than traits that are hinder the survival of the organism.

Answer 5

Natural selection is one of the two main driving forces of evolution, next to genetic drift.

Natural selection is necessary in the harsh environment of Earth, where organisms are constantly competing for survival and domination.

In nature reproductive opportunities are limited, not all organisms will survive to be able to reproduce. In natural selection, any traits that help an organism survive long enough to reproduce will pass these traits on to the next generation.

Over time these changes in traits will accumulate, and this is how evolution occurs.

Take, for example, two deer. One was born with long legs, and one was born with short legs. Now both of them are trying to escape a lion that is chasing them. Which deer is more likely to outrun the lion and survive? If you said the long-legged deer, you are right. So, the short-legged deer is killed and unable to reproduce. However, the long-legged deer is able to pass on her traits and produce a new generation of long-legged deer. The process continues, driving the evolution of these deer.

This is basically what natural selection is.

Answer 6

Because selection is differential selection. The variations that have the best reproductive success in the immediate environment are those that are differentially selected and not randomly selected.

Answer 7

The best traits from both parties are chosen and hopefully passed on to the next generation.