Natural Selection

Natural selection is a process by which organisms with traits that help them survive are more likely to pass those traits on to their offspring.

However, not all traits can be passed down. Only inherited traits like eye color or beak shape can be passed to the next generation. Over time, traits that improve survival become more common in a population.

Take the Galápagos tortoises as an example. Tortoises with long necks can reach high-growing fruit, while short-necked tortoises struggle to find food.

Over generations, more long-necked tortoises survive and pass this trait to their offspring.

Like these tortoises, every species depends on its traits to survive. These traits, called adaptations, help organisms thrive in their environment.

For example, in the Arctic during winter, the arctic hare’s fur color changes to white, blending into the snow to avoid foxes. In summer, its fur turns brown or gray, helping it hide among rocks and plants. This adaptation increases its chances of survival.