Hello there! ^^
I just watched a very interesting documentary called Secrets of Our Living Planet. It was the fourth and last episode called Waterworlds. It made me want to watch the previous episodes as the writers of the series explain very clearly how our ecosystems work and how they are all connected and interdependent.
For example we discover how the tiger survives thanks to a small crab in the Gange river in India. We know how the tiniest creatures play a very fundamental role in an ecosystem. If they disappear somehow, it’s a whole system that collapses.
Take the phytoplankton when they reproduce, not only they’re the reason why huge marine creatures travel thousands of miles to ba able to nourish themselbes, but they’re also the reason why the ocean temperature arises and can provoke rain! A very essential part for such a small specie.
Watch the third episode The Magical Forest here.