Populations
Whether it is a school of fish, a pride of lions, a colony of ants, or the bustling city you live in, every living thing belongs to a population. But what happens when a population gets too big for its home, and how do different species compete for survival?
You Are Part of a Population!
Absolutely! A population is just a group of organisms of the same species living in a particular place at the same time. You, your family, and everyone in your city are part of the global human population.
They run out of resources! No population can grow forever. Eventually, they will eat all the available food, run out of clean water, and completely run out of physical space to live, forcing them to compete or move.
Put Your Instincts to the Test
Think about how animals survive in the wild. Pick an answer for each scenario, then see if your instincts were right.
They run out of space and resources! Populations cannot grow forever because they are strictly limited by the available food, water, and physical room in their habitat. They will eventually crowd each other out.
The wolf population will decrease! Populations in nature are permanently linked. If the food supply drops, the predator population will starve and shrink in direct response.
It is destroying their natural habitats! As the human population expands by millions every year, we build cities and farms over the natural homes of other species, forcing them to move or face extinction.
Understanding the Science
To understand how ecosystems stay perfectly balanced, we have to look at how living things compete, multiply, and depend heavily on each other. Tap the cards below to reveal the keywords of ecology.
Key Concepts
Population
Tap to learn moreA specific group of organisms of the exact same species living in a particular place at the same time, like a school of fish in a reef or humans in a city.
Competition
Tap to learn moreThe daily, fierce struggle between organisms to survive in a habitat with highly limited resources like food, water, and physical space.
Interdependence
Tap to learn moreHow different populations rely heavily on each other to survive, just like a population of bees needing flowers for nectar, and flowers needing bees for pollination.
Predator and Prey
Tap to learn moreThe natural seesaw cycle where the population of a hunter goes up and down based directly on the availability of its food.
Exponential Growth
Tap to learn moreWhen a population grows at a staggering rate by doubling over and over, like bacteria dividing in a dish or weeds taking over a lawn.
Parasite
Tap to learn moreA living organism, like a mosquito or a clinging vine, that survives by feeding directly off the nutrients of another living population without instantly killing it.
Endangered Species
Tap to learn moreA population of animals, like wild cheetahs or rhinos, that is at an incredibly high risk of becoming extinct forever, usually due to severe habitat loss or hunting.
Habitat
Tap to learn moreThe natural home or environment of an animal, plant, or other organism, providing all the critical resources (food, water, shelter) it needs to survive.
Interactive: Population Dynamics Modeler
Ecosystems operate on a delicate mathematical balance. Set up your ecosystem variables below, ensuring you select the correct natural predator for your prey. Then run the 10-Year Simulation to see if the populations survive. Pay close attention to the graph and the final analysis report!
Apply Your Knowledge
Let us see if you can correctly identify the essential scientific terminology associated with populations and ecosystems.
Match the Concepts
Click a scientific term to select it, then click the matching description to place it.
Real-World Challenge
Imagine a local council wants to build a massive new shopping centre right in the middle of a natural woodland area. As an ecologist, how would you explain the chain reaction this would cause to the interconnected populations of insects, birds, and predators currently living there?
What Has Changed Since This Episode Aired
This episode originally aired in 1995. Since then, global populations have shifted dramatically, and our scientific understanding of ecology has improved significantly!
Updated: The human population has surged incredibly fast since the 1990s. In late 2022, the global population officially surpassed 8 billion people, putting even more pressure on the Earth's natural resources and wildlife habitats!
Updated: Incredible modern genetic mapping has revealed that cheetahs suffer from a "genetic bottleneck," meaning their gene pool lacks diversity, which makes them very vulnerable to disease. Modern conservationists now carefully track cheetah genetics across global zoos to pair up the healthiest mates and strengthen the population.
Updated: Yes, this is a massive conservation success story! In the 1980s, there were fewer than 30 condors left in the entire world. Thanks to aggressive protection and intense breeding programmes, there are now over 500 California Condors soaring in the wild today.
Test Your Understanding
Answer these 10 questions and get instant feedback. How many can you get right?
Results
Your score:
Reflection
Think about the town or city where you live. What are three natural resources (like fresh water or green land) that your local human population competes for? How can you help ensure those essential resources are not wasted?
Episode Discussion
Share your thoughts on this Bill Nye episode