Part one: | The beach,a natural trea sure trove
Nature walks can be fun, energizing and educational at the same time. In Part One, we will look at
what we can find on a marine walk. In Part Two, we will discuss our fascinating forests.
First of all, when you are walking on the beach you may be able to spot tracks. Birds and crabs leave
footprints behind, especially in wet sand. On sandy beaches you will also be able to find interesting
holes, made by crabs that were digging for food in the mud.
You may also come across jellyfish, as these are often washed up on the beach by the tides. They
have no eyes, ears, heart or head and are mostly made of water. They look like a bag with arms,
which are called tentacles. These contain poison, which helps them catch food. Even when they are
out of the water or in pieces the tentacles may sting you, so they are best left alone.
Other animals you may find are coral and barnacles. The latter are marine animals that are related to
crabs and lobsters and live in shallow waters. They like to attach themselves to hard materials, so
you are likely to find them stuck to a piece of wood.
You may also see what look like small gelatinous blobs but are actually fish or worm eggs.
If you are lucky, you may find a fossil. In essence, this is an animal that died and got buried in a sea
bed. They are likely to look like a piece of rock with an imprint of an animal skeleton. Their history is
very interesting.
For an animal to become fossilized, it has to be buried in mud, sand or soil. If an animal dies but is
not buried, it is more likely to rot away, be swept away by wind or water, and/or be eaten by another
animal. Over millions of years, the animal remains become buried deeper and deeper; the mud,
sand or soil compresses and slowly becomes rock. Their bone or shell starts to crystallize, because
of surrounding minerals and chemicals. Ideally, the temperature stays relatively constant throughout
this process. Sometimes the fossil dissolves completely and just leaves an imprint. At other times,
waves, tides and currents slowly make the rocks erode, which allows the animal remains to break
off, ready for you to find.
What you will definitely find a beach are shells. These were once the homes of animals such as
snails, barnacles and mussels, consisting of a hard layer that the animal created for protection as part
of its body. After the animal has died, its soft parts have rotted or have been eaten by other animals.
such as crabs. What is left is a beautiful seashell for you to admire and take home if you wish.
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Exam tip
In the exam, you may have to complete labels of pictures, diagrams, flow charts, etc. so
it helps if you can think visually. If you do not have a visual imagination, start practising
by trying to visually represent written information where possible.
2. Cover the diagrams below. Now try to make a drawing to represent the information in the
paragraph about how fossils are formed.
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