It took hundreds of thousands of years for the human population to reach 1 billion and in less than 200 years that has increased to nearly 7.5 billion people. Many scientists calculate the sustainable population to be about 2 billion people which means we need to manage our resources and food production very carefully to cater to the extra 5.5 billion people as populations have grown farming practices have become more intensified to maximize crop yields and ensure that we can feed our ever-growing population. Fertilizers and pesticides are used on crops and animals may be kept inside in more densely packed sheds to maximize milk yields or egg production or speed up the time needed for the animal to be ready to be sent to the market for meat. Organic farming currently accounts for about one percent of agricultural land worldwide. It focuses on sustainability and is thought to have less detrimental effects on the environment than conventional farming this has led to it being proposed