Listening CAE 6 Part 4 Butterflies

In North America alone there's over 700 butterflies. They play the key role in the ecosystem as pollinators. Even though they're responsible for pollinating many flowers, they are less effective than 21. ...

There are lots of reasons why butterflies are attracted to plants. The key reason plants attract them is if those plants have a strong 22. ... .

In areas where there are lots of butterflies, it reflects how nature is thriving, as butterflies are an essential part of the ecosystem. In fact, butterflies are a vital link in the food 23. ... , as it acts as both prey and predators.

Interestingly, 24. ... can also buy and breed some species of butterflies to their advantage.

Some butterflies can be utilised as a good form of 25. ... control, by eating insects that damage harvests. Scientists also use the presence of butterflies as a measuring stick to a certain phenomenon in nature they're keen to note.

The butterfly's movement tend to be good 26. ... of climate change. As they are much more sensitive than other animals, they can notice changes in the environment and act as an early warning system.

As an example, a type of butterfly called the Checkerspot now populates areas at higher 27. ... than in the past due to global warming.

Another interesting fact about butterfly is that some special species can attract 28. ... to an area and boost the local economy. For example, in Mexico, people come from far and wide to see the Monarch butterfly.

Another species that is special is The European 29. ... Brown butterfly,

which produces a natural 30. ... which may be of use to humans.