Variation
is how living things (organisms)differ
from each other. Organisms which are able to reproduce
with each other to produce more organisms which are also able
to reproduce are members of the same species.
Variation exists between members of the same species (it is
how we can tell each other apart) and between species. In the
picture below how many differences can you see between me and
the Cheetah?
Dr Parry and the Cheetah are
different species. They show lots of variation.
Variation
between members of the same species
Dogs
are all members of the same species and can breed with each
other. In the pictures below how many differences can you see
between the different types (breed) of dog?
Two
features may be linked together. Taller people, for example,
might have longer feet. To see if there is a relationship
or correlation between two features we could
carry out an investigation. Would you expect taller people to
have a larger shoe size? The graph below shows an investigation
which measured these two things for three classes of year 7
pupils at Southmoor School.
The
graph shows that, on average, the larger the shoe size the taller
the person. The red line is a line of best fit
through the dots. However, as you can see there is a lot of
variation between people.
