Predation and Competition: What's Happening in Ecosystems

Predation and competition are important parts of how ecosystems work. They influence which plants and animals thrive and how they interact.

Predation:

• Predators help keep the number of prey animals balanced. This helps prevent any one species from taking over.
• For example, when wolves were brought back to Yellowstone National Park, the number of elk decreased. This allowed plants to grow back healthier.
• It's estimated that a predator can eat between 1 to 5 prey animals each day, which can greatly affect the prey population.
• When the number of prey changes, it doesn’t just impact them. It affects the whole food web, as other animals rely on those prey for survival.

Competition:

• Competition happens when different species want the same resources, like food, water, or space.
• There’s a rule called the competitive exclusion principle. It says that two species fighting for the same resources can’t live together forever.
• In one study, they found that 66% of species decreased in number when there wasn’t enough food or other resources to go around.
• Sometimes, to reduce competition, species adopt different ways to use resources. This is called resource partitioning. It can help increase the number of different species in an ecosystem.

Overall, both predation and competition play key roles in natural selection. They help species adapt and survive, keeping ecosystems balanced and healthy.