A miniature ecosystem has been thriving in an almost completely isolated state for more than forty years inside a round bottle. What’s amazing is that it has been watered just once within that span of time.
The original single spiderwort plant that was put inside the bottle has grown and multiplied by spurting out seedlings, resulting in a very lively ecosystem. It is being given access to light which allows it to continue to photosynthesize.
A miniature version of the water cycle happens within the ecosystem when water builds up on the inside of the huge bottle and then rains back down on the plants. When the leaves die, they fall off and rot at the bottom of the bottle. This produces carbon dioxide and nutrients that are required for more plant matter to grow.