Issues that concern the environment do not always have clear lines between liberal and conservative views. Some local issues concerning growth and pollution can bring conservative and liberal activists together and issues that involve the balance of economic and environmental factors are often quite complex in their ideological impacts. However, there are certain political positions regarding the environment that tend to be viewed as either conservative or liberal. The major fault lines between liberals and conservatives usually focus on economic growth versus protection of the environment. Liberals typically support protecting the environment even if it costs jobs while conservatives traditionally give greater consideration to balancing the needs of business and industry against the environmental cost of a particular action or policy. Offshore oil drilling offers a good example of the division between conservatives and liberals on the environment. The conservative position is that drilling creates jobs and increases the domestic oil supply. Both of these benefit the economy. Liberals answer that the economic benefits do not outweigh the visual blight from oil rigs off the coast and the risk of environmental damage from oil spills. Liberals and conservatives also take very different views of climate change. Conservatives do not believe that global warming is caused by man. Therefore, they do not support forcing reductions in the use of fossil fuels. They also strongly oppose higher taxes on fossil fuels to discourage their use. Liberals consider global warming to be almost entirely caused by human use of fossil fuels and industrial growth. They support drastic reductions in activities that they believe are bringing catastrophic warming to the planet. Liberals believe that any reduction in economic activity that is caused by tightening regulations to prevent global warming is a cost that is worth paying to prevent the risks they see from climate change. While global warming is currently the most prominent topic in news coverage about the environment, there are many other issues where liberals and conservatives have not reached a consensus. Habitat preservation is a subject that is frequently discussed on the state and local levels of government. Liberals believe that biodiversity is so critical that substantial expenditures are worthwhile to preserve habitat for endangered species. While conservatives also support preservation, they are much more likely to be concerned about the cost of habitat preservation. The debate often centers on exactly how much land should be set aside. Liberals generally support setting aside much larger areas for endangered species than conservatives find acceptable. The safety of the food supply is another subject where there is a split between liberal and conservative opinion. Both conservatives and liberals want safe and plentiful food to be available in both industrialized and developing countries. However, there is strong disagreement over whether or not genetically modified food is safe and what level of pesticide use is acceptable. Conservatives tend to believe that there are many pesticides that are safe and effective and that the small doses in the food supply are harmless to humans. Liberals are extremely concerned about the potentially toxic effect of pesticides that may get into the food and water supply. They also worry that the amount that is consumed over a lifetime is cumulatively unsafe for many people. They are concerned that cancer and some degenerative diseases may be caused by pesticide consumption. Genetically modified foods can greatly increase crop yields and improve the nutritional value of many foods. They can also improve the plants’ resistance to crop-destroying pests. Conservatives tend to feel genetically altered crops are safe and that they make much more food available at a lower price. They believe that the provision of nutritious food to the poor at a low cost is much more important than any risks that genetic changes in the food supply might bring. Many liberals strongly oppose genetically modified crops. They believe that these crops are potentially harmful and that tampering with the natural genetic design of plants is dangerous. While conservative and liberal opinion differs on many topics that relate to the environment, the debate between the two views often brings out important factors that would never be examined without a vigorous discussion of the issues.