OVERVIEW
Predator and prey populationsA predator is an animal that hunts, kills and eats other animals for food. Prey is a term used to describe organisms that predators kill for food.
Predator/prey relationships can be illustrated in a diagram called a food chain or food web.
- A food chain shows the linear flow of energy between organisms
- A food web is all of the food chains in an ecosystem
(see the difference in the image below)
Predator/prey relationships can be illustrated in a diagram called a food chain or food web.
- A food chain shows the linear flow of energy between organisms
- A food web is all of the food chains in an ecosystem
(see the difference in the image below)
Producers make their own food using energy from an abiotic source. For example plants carry out photosynthesis to make food using light energy from the sun. Consumers get food from a biotic source by eating the biomass of producers or other consumers.
Within food chains and webs there are organisms that will only consume particular types of food:
- A herbivore is an organism that only consumes plant material.
- A carnivore is an organism that only consumes animal material.
- An omnivore is an organism that will consume both plant and animal material.
- Predator species need to be adapted for efficient hunting if they are to catch enough food to survive.
- Prey species must be well adapted to escape predators for their species to continue.
If an organism is removed from a food chain or web all together, for example due to overhunting, then this can have a catastrophic effect on the other populations in the food web.
The most abundant organism in a food web is typically the primary producer, which is usually a type of autotrophic organism capable of synthesizing its own food through photosynthesis or chemosynthesis. In many ecosystems, such as terrestrial environments and oceans, plants and algae are the primary producers and thus often the most abundant organisms in terms of biomass and population. These primary producers form the foundation of the food web, providing energy to higher trophic levels through consumption by herbivores and subsequent transfer up the food chain. Therefore, trees, plants or algae are likely to be the most abundant organisms in many food webs.