An invertebrate is an
animal without a backbone.
Invertebrates are everywhere and are very important to our environment.
They live on the land (e.g. insects, arachnids, snails, worms) and in
water (e.g. crabs, jellyfish, squid, clams).
beetle
crab
spider
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butterfly
Invertebrates that feed on other invertebrates are predators. When invertebrates
feed on other insects or animals, it helps to keep populations under control.
By eating other plant eating insects, predators make sure there aren’t too many
herbivorous invertebrates in the environment.
They can also help to reduce the number of pests.
The droppings of predator invertebrates also provides important nutrients to the soil.
praying mantis
spider
mosquito
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centipede
Most invertebrates are herbivores. Herbivores feed only on plants. They provide
a very important function.
By eating plants, herbivorous invertebrates help to fertilise the soil with their
droppings. This helps crops to grow full of nutrients for other animals to eat. The
nutrients in the soil assist young seedlings to grow.
Herbivorous invertebrates also help to reduce the number of weeds.
butterfly
snail
millipede
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grasshopper
Pollination helps plants to reproduce. Pollen is produced in the
anther of a plant (male organ) and is transferred to the stamen
(female organ). This is pollination. It can be transferred to the stamen
of the same plant or another plant of the same species. The stamen then produces a
seed for a new plant to grow. More than half of all flowering plants rely on insects for
pollination.
Many winged insects are pollinators as they fly from plant to plant collecting and
spreading pollen. Often these insects feed on nectar or the pollen itself.
butterfly
bee
wasp
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ladybug
Seeds from plants can be carried by insects to other locations to feed on.
This is an important process that helps to ensure successful seed growth.
Ants can carry seeds a long way from the plant. An ant nest contains soil
high in nutrients which is protected from other insects. In these conditions,
a seed has a high chance of successful growth without competing for soil
and water from other plant life.
ants
beetle
wasp
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seed bug