* Natural Selection: The process by which organisms better adapted to their environment tend to survive and reproduce more successfully.

* Physical Adaptations: Traits or characteristics that allow an organism to function better in its environment (e.g., camouflage, sharp claws, strong beaks).

* Inheritance: Organisms inherit their traits from their parents through genes.

How it works:

1. Variation: Individuals within a population have slight differences in their traits.

2. Survival Advantage: Individuals with adaptations that make them better suited to their environment (e.g., finding food, avoiding predators) are more likely to survive.

3. Reproduction: These surviving individuals are more likely to reproduce and pass their beneficial traits onto their offspring.

4. Evolution: Over time, the frequency of the advantageous traits increases in the population, leading to evolution.

Example: A species of bird with beaks better suited to cracking open seeds is more likely to survive in an environment with lots of seeds. These birds will reproduce more, passing on their "seed-cracking" beak genes to their offspring, making this trait more common in the population.