3.6.  Read the passage paying attention to the words and word combinations in bold type.

Humans are one of about 1.75 million identified species. Many scientists believe that millions more species inhabit our world yet remain unidentified. Some species have become extinct after less than half a million years, while other species have existed almost unchanged for many millions of years. Contrary to popular belief, extinction is a natural process. For hundreds of millions of years, extinctions have been occurring naturally, as part of the evolutionary process. Some extinctions have been caused by natural disasters, such as volcanic eruptions. Others have been the result of environmental changes, such as shifts in climate. Based on fossil record, the average rate of extinction has been one species out of every million per century. Sometimes extinctions occur on a very large scale, with hundreds or thousands of species becoming extinct over a relatively short time. An example of this is the dinosaurs and their contemporaries, victims of a mass extinction that took place at least 65 million years ago.

Although extinction itself is nothing new, the current high rate of extinction is. Today experts say that at least three animal and plant species become extinct every day, a rate much higher than any in the past 65 million years.

This worldwide endangerment of animals and plants is a phenomenon of the 20^th century. It is a product of the continuing use of more and more natural resources for a constantly growing human population. Thus, many wildlife species become endangered because there is less wild space for them to inhabit.

Unfortunately, we are witnessing a great wave of extinctions. The current rate may be as high as several species per day. Among the species of most concern are those confined or endemic to a single island or group of islands. These «island» territories can also be cave systems, parks, and reserves that people have created.

When species are isolated, they are vulnerable to environmental changes and natural catastrophes. These are not the only causes of endangerment to species. Hunting and air, water and land pollution are also responsible for reducing species numbers. So, directly or indirectly, species are becoming threatened because of increasing human population.

• Use the word combinations in bold type in sentences of your own.

• Give a summary of the text.

3.7. Which of these statements do you agree with? Which do you disagree with? Discuss your opinion with a partner, and add any other statements that you agree with.

1. More animal reserves should be created and more work should be done to help endangered species to breed in captivity.

2. We can’t afford to worry about animals when millions of human beings are starving.

3. We shouldn’t be too worried about certain species becoming extinct, there are so many species which remain.

3.8. Speech practice

• We are the main threat to wildlife; there should be much stricter laws to protect the habitats of wild animals.

• Make an angry speech against human activities that threaten wildlife.

• You are an environmentalist. You are speaking at a conference in favour of healthy, friendly to the environment lifestyle.