Que sont les populations et les communautés ?

A population is a group of organisms of the same species that live in the same area. A community includes all the different populations that live and interact in that area.

Organisms in a community depend on both biotic factors, such as other organisms, and abiotic factors, such as water, sunlight, air, and soil, which together influence their survival and distribution.

These factors often lead to interactions between populations. For example, when populations compete for limited resources, such as food, water, or space, one population may outcompete another over time.

Some interactions are predatory, like a snake hunting a frog. This interaction can reduce the number of frogs in an area.

Other interactions are mutually beneficial, like bees collecting nectar while also helping flowers reproduce through pollination.

Changes in abiotic factors, such as a drought, can cause organisms to die or move to new areas. This change reduces the population size in the affected area.

When one population changes, others are also affected. This shows that communities are connected systems shaped by interactions and resource availability.