"Natural Science 4" is an interactive encyclopedia that includes scientific information in the understanding of fourth grade students, wonderfully illustrated and animated.
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* Chapter 2 Lesson 13 *
* Feeding relationships between living things *
Living things need food to grow and develop. In this process they depend on each other. In this way, feeding relationships are established between living things of the same environment, called trophic chains.
The food chain consists of several links. Each link represents a species of living thing. It is always based on plants. They produce their own food through photosynthesis. Any living thing that can prepare its own food is called a producer. Plants are the food of herbivorous animals which, in turn, are hunted and eaten by carnivorous animals. Another category of animals consists of omnivorous animals. They eat both plants and animals.
A living thing that feeds on plants or animals is called a consumer. Those that hunt are the predators, and those that are eaten are the prey.
Did you know that there are also plants that can be eaten? They are called carnivorous plants. Sarracenia is a carnivorous plant with cup-shaped, purple-cherry colored leaves that secrete a sticky and highly aromatic substance. Insects fooled by the emitted aroma and put to sleep by that substance can then be consumed by the plant.
Let's discover some food chains!
In the terrestrial environment the owl eats mice. They, in turn, consume crickets. Crickets are insects and feed on plants.
How many links did you count?
On average, a food chain can have 3-5 links, but there are also longer chains.
The industrious bee flies from flower to flower to collect the pollen of the flowers with which she feeds her brood and daughters. They are caught in flight by the prigori. They are vulnerable to snakes. Snakes are eaten by large birds of prey, such as the buzzard.
Let's now observe an aquatic food chain!
Little fish feed on algae. They are caught by large and fast predators such as tuna or sharks. They in turn fall prey to man.
As you have well noticed, man is also a link in the food chain.
Also from the aquatic environment we can form other trophic chains.
Phytoplankton make up most of the plant matter in the oceans. It develops very quickly, constituting the first stage in the trophic network of the oceans. The tiny animals that make up the zooplankton feed on it. This includes fish fry and small animals related to crabs and shrimps. The flying fish is a big plankton eater. The wandering albatross soars above the waves trying to catch fish.
Once animals die, their bodies can be food for other living things. Earthworms and bacteria transform the remains into substances that enter the composition of the soil, thus being nutritious for plants. These are called decomposers.
In nature there is a balance between the categories of living things. The disappearance of some plant species can lead to the extinction of herbivore species, which can affect the lives of many carnivores.
What can be the cause of such imbalances?