Rainforests once covered 14% of the Earths surface, now they cover a mere 6%. It is impossible to tell exactly how much of the Rainforest is being destroyed but experts estimate upwards of 80,000 acres each day. The Rainforest is home to about 50% of the worlds species and everyday we are losing some 135 plant, animal and insect species which is about 50,000 each year. Overall tropical deforestation rates are 8.5 percent higher now than in the 1900's. Reasons for this include logging, cattle ranching, dam-building and mining, but also due to subsistence agriculture. One of the most serious affects is oil companies searching for new oil deposits. This is very damaging as often large roads are built through untouched forests in order to build pipelines and retrieve the oil. Scientists have found 3,000 plants that are active against cancer cells 70% of these are found in the rainforests. Also 25% of the active ingredients in today's cancer-fighting drugs come from organisms found only in the rainforest