Understanding What Natural Selection Is
Natural selection is the process by which organisms with traits that help them survive are more likely to reproduce. Over time, these helpful traits become more common in a population.
How Natural Selection Works
When resources are limited or environments change, individuals with beneficial traits—such as better camouflage, resistance to disease, or improved hunting ability—have a higher chance of surviving and passing those traits to their offspring.
Examples of Natural Selection
Classic examples include peppered moths changing color due to pollution, antibiotic resistance in bacteria, and finches in the Galápagos evolving different beak shapes to match available food sources.
Why Natural Selection Matters
Natural selection explains much of Earth’s biodiversity. It shows how species adapt, survive challenges, and evolve new forms over long periods. It is one of the central ideas in biology and evolution.
Key Characteristics of Natural Selection
• Requires variation in traits within a population.
• Favors traits that increase survival or reproduction.
• Acts gradually over many generations.
• Leads to adaptation and evolutionary change.
The Simple Takeaway
Natural selection is the engine of evolution: individuals with useful traits survive more often and pass those traits on. Over generations, this shapes species and helps them thrive.