Combine the two sentences into one, using a non-defining relative clause.

1. Boreal forests cover vast areas in Canada, Alaska, and Russia. They are also called Taiga.

2. Polar bears are endangered animals. Their natural habitat is the Arctic.

3. Julie Arblaster focuses on studying climate change. She is an Australian scientist.

4. Antarctica is Earth's least populated continent. It is surrounded by the Southern Ocean.

5. The natural world is the world of living things. Living things include plants and animals.