How plants make a living

A plant’s worldview is different from an animal’s

Plants form the basis for every ecosystem on Earth exposed to sunlight. We, as animals, depend on them for food, shade, and carbon and nitrogen cycling. As plants evolved from photosynthesising bacteria that appeared over 2 billion years ago, they transformed the early carbon-dioxide-heavy atmosphere into oxygen-rich air.

Plants take a different approach to life from ours. They don’t go out looking for anything they need. They make their own food using what they absorb from the air and soil around them, and reproduce by spreading their pollen and seeds on the wind and on the bodies of foraging insects and other animals. They’ve adapted to survive in a single spot (or, in the case of phytoplankton, where the currents take them).

To survive and reproduce, plants invest their resources in three different ways. Some put their energy into outdoing the competition, some into enduring environmental stresses, and some into quickly making and spreading as many seeds as they can.

Within those strategies, there are different tactics. For example, should a plant grow an extra shoot, making room for more leaves to collect light and carbon dioxide, or put more energy into making roots to help it extract more water and nutrients from the soil? It all depends on how much of the things the plant needs is available in its environment.

Lead image:

Bernadette Health/Shutterstock

References

About this resource

This resource was first published in ‘Plants’ in May 2016.

Topics:
Microbiology, Ecology and environment
Issue:
Plants
Education levels:
11–14, 16–19, Continuing professional development