Global challenges

Ecologists study the distribution of living organisms in habitats to find out how healthy it is. They use many different sampling methods to provide quantitative data which is then analysed.

Biodiversity is a measure of how many different species live in an ecosystem. Human activities like changing land use, deforestation and peat bog destruction reduce this.

Factors such as the increase in population, new pathogens and overhunting can result in food scarcity. Improved farming techniques, sustainable fisheries and biotechnology can help increase supply.

Health is the state of physical and mental well-being. Factors can work together to both physical and mental health. A disease is a disorder that affects an organism’s body, organs, tissues or cells.

Pathogens are everywhere. The body has evolved defences that act to prevent pathogens entering it. If a pathogen does enter the body then the immune system helps to fight it off.

The chance of developing a non-communicable disease can be increased or decreased depending upon a person’s lifestyle or the genes they inherit. Two common types are cancer & cardiovascular disease.

Scientists find links between diseases and their causes. The information is used to reduce the number of people with the disease by giving lifestyle advice or developing new ways to fight the disease.