The whole pond

About this video

Turn over a flat stone in a garden and you find a small world. A pond, a forest or a desert is the same thing on a bigger scale. This video shows what ties living things to the place they live, and to each other.

A habitat is the place where a living thing makes its home. A good habitat gives it what it needs to stay alive: food, water, shelter and space. A trout's habitat is a cold, clean river. Put a trout in a desert and it soon dies, not because it is weak, but because that is not its habitat.

Then the video zooms out. One frog is an organism. All the frogs in a pond form a population. All the populations together, frogs, fish, reeds, water beetles and tiny green algae, form a community. An ecosystem is that community and the non-living things around it: the water, mud, rocks, air, sunlight and temperature, all acting on each other. Plants take water and minerals from the soil, fallen leaves rot and become soil again, and trees shade the ground so different plants grow beneath them.

An ecosystem can be as small as a puddle or as big as an ocean. Along the southern shore of the Caspian Sea, the Hyrcanian forests stretch for about 850 km, with more than 3,200 kinds of plants and the Persian leopard. This video goes with the lesson Habitats and Ecosystems in Knaph's Biology Level 1 course.

Transcript

1. 0:00Turn over a stone, and you find a small world. A pond is a bigger one.
2. 0:08A habitat is a living thing's home. It gives food, water, shelter and space. A trout's habitat is a cold, clean river. In a desert it soon dies. Not because it's weak. That's just not its habitat.
3. 0:22One frog is an organism.
4. 0:28All the frogs in the pond are a population.
5. 0:34Add the fish, the reeds, the beetles and the algae. That's a community.
6. 0:40Now add the water, the mud, the air and the sunlight. Living and non-living together. That is an ecosystem.
7. 0:48The parts act on each other all the time. Plants take water and minerals from the soil. Fallen leaves rot and become soil again. Trees shade the ground, and other plants grow beneath.
8. 1:02An ecosystem can be a puddle or an ocean. By the Caspian Sea, the Hyrcanian forests stretch about 850 kilometres, with over 3,200 kinds of plants.
9. 1:14An ecosystem is living things and their surroundings, working as one.