Niche and competition

Re-cap - Ecosystems An ecosystem consists of all the living in a particular and the components with which the organisms interact An ecosystem is a community of , animals and smaller organisms that live, , reproduce and interact in the same habitat or environment. The non-living components include , pH, , CO2 , O2 and other chemicals. plants, temperature, habitat, light, feed, non-living, organisms,

Today we are learning about niche and competition Does any one know what the word niche means? A niche is the role that an organism plays within a community. A niche includes the use organisms make of the resources in their ecosystem, including light and nutrient availability. The interactions include other organisms in the community including competition and predation and the conditions the organism can tolerate such as different temperature ranges.

All organisms in an ecosystem have a particular niche. What is the role of plants in an ecosystem? Plants are the producers. This means they can photosynthesise and make their own food. There are exceptions to this and some plants supplement the poor nutrient levels in their ecosystem by digesting insects. Can you name any plants that do this? Butterwort, Sundew, Venus fly trap

Animals have a variety of niches in an ecosystem often associated with their feeding level. These levels are primary consumer, secondary consumer, tertiary consumer, etc.. Primary consumers are animals that feed directly on the plants and would be called herbivores Secondary consumers are animals that feed on the primary consumers. Tertiary consumers are animals that feed on the secondary consumers.

Organisms are often grouped in a niche in relation to where they get their energy (food). This includes herbivores, carnivores, omnivores and decomposers. You should know the difference, test yourself? Herbivores Carnivores Omnivores Decomposers

Relationships between organisms Organisms in an ecosystem are influenced by their relationships with each other. If organisms require the same or similar resources or resources are in short supply then they will need to ‘fight’ for them. This is called competition. Plants will often compete for light, space and available nutrients. Animals will often compete for food, space and reproductive mates. As a result of competition between organisms their success and numbers in the ecosystem will be affected.

Competition There are 2 types of competition Interspecific – between members of different species Such robins and blue tits for insects in a garden. They require similar but not exactly the same resources. Intraspecific – between members of the same species Such as all the robins getting insects in a garden. They all require the same resources to survive. Which of these types of competition will be the most intense and why?

Relationships between organisms Another relationship that will affect how successful organisms are is that between predators and their prey. Predators get their food by eating other animals. The numbers of predators will affect the numbers of their prey (the animal being eaten). Examples of predators include pine marten, eagles, wolves and bears. Take a look at the graph and think about how the predators and prey affect each other, what do you notice?

What did you notice? As the prey numbers increase the predator numbers increase. As the predator numbers increase the prey numbers decrease. As the prey numbers decrease the predator numbers decrease. Can you explain this? Could there be other factors affecting the populations?

We have been learning about niche and competition What is a niche? A niche is the role that an organism plays within a community. What kind of resources will organisms be using in their ecosystem? Light, temperature and nutrient availability. What types of interactions occur between organisms in a community? Competition and predation.

We have been learning about niche and competition What are the 2 types of competition? Intraspecific and interspecific Which one of these is between members of the same species? Which one of these is between members of different species? How will they affect the different organisms involved? What is predation? How do prey and predators affect the numbers in each population?

Investigation You are going to Plan and Carry out an investigation into competition between cress seeds for space to germinate The teacher will introduce and discuss the investigation with the class. There will be an initial planning phase that must be completed before carrying out the investigation. The investigation will then be carried out.