Biodiversity

Biodiversity can be described as “the variety and variability of biological organisms.”¹ When an area is biodiverse, this means there are many different species sharing the same ecosystem. Having biodiversity is extremely important for many reasons, including the reduction of infectious diseases being transmitted from animals to humans, otherwise known as zoonotic diseases.² Currently, zoonotic diseases account for 75 percent of all emerging diseases in people.¹⁴

Biodiversity helps:²

• Reduce the environments in which diseases grow and multiply (reservoirs)

• Decrease the population of carriers of diseases (vectors)

• Limit the interactions between vectors and reservoirs²

When the risk of infectious disease is lowered due to biodiversity this is called this the dilution effect. During the destruction of forests and other natural areas of the world, we risk reducing biodiversity while increasing the presence of zoonotic disease.²

Climate change is a major driving force for biodiversity loss.⁵ Climate change causes the fluctuation in temperatures which presents as floods, droughts, hurricanes, and other natural disasters.¹⁵ With such drastic changes in environments, many species will not be able to continue to survive in their regular habitats. Biodiversity loss also affects an ecosystem's ability to act as a buffer to carbon emissions which creates a viscous cycle.¹⁸ See Postponing Talks for more information.

Biodiversity is also affected by:

Natural environments being converted for agricultural and industrial use

• • Areas used for agriculture and industrial purposes have impacted 85% of wetlands, 75% of land, and 66% of ocean space according to current data.⁹
    

Pollution

• • In 2014, it was estimated that over 5 trillion pieces of plastic were floating around in the ocean.¹⁰ This greatly effects marine species.

  • Waste created by humans has been well documented as sites of zoonotic reservoirs and food for zoonotic vectors.¹³

  • See Pollution and Waste Management for more information.
    

Native species being dominated non-native species

• • Many non-native species bring disease to areas where they are introduced, posing a threat to both native species and humans.¹²

  • Invasive species are one of the leading causes of extinction in the United States.¹²
    

Population growth and urbanization

• • Since 2000, city growth has increased exponentially to accommodate the world's growing population.⁹ What were once biodiverse natural areas have now been converted to cities.

  • See Urbanization and Urban Planning for more information.
    

Exploitation of plants and animals

• • Meat production and the consumption of wild animals have been linked to the increasing rates of zoonotic disease.¹⁴

  • The exploitation of plants and animals causes humans to come in contact with a variety of species which carry disease.¹¹

  • See Deforestation for more information.

COVID-19 is an example of a zoonotic disease that has been intensified by biodiversity loss. Researchers have found that an increase in biodiversity destruction has led to circumstances "that have favored and, in fact, made possible, the insurgence of the COVID-19 pandemic."¹⁶ Bats, who have been identified as being the most likely reservoir of the novel virus, have come in contact with humans more frequently due to man-made factors such as urbanization, deforestation, and species exploitation.¹⁶ Environments that were once natural habitats have been converted for human use. Barns, houses and other areas regularly visited by people have become new homes to bats increasing the likelihood of the transfer of zoonotic disease.¹⁶

Pangolins, a mammal known for their unique look, have also become of source of the viral spread due to illegal trapping and trade.¹⁷ Like humans, pangolins are hosts to COVID-19, so they too are getting sick and spreading the virus.¹⁷ Poachers, who have exploited this animal to sell as a pet, are coming in contact with pangolins as well as those who buy them or visit the markets where they are sold.¹⁷

(Pangolin pictured in second image below)

According to current data, if we do not protect our environment we are at risk of losing one million species in the next coming decades.³ Estimates for how many species are going extinct each year range from 200 to as much as 100,000.⁹ Amphibians are the most vulnerable animal at risk right now.³ This poses a specific threat of increased rates of infectious disease since many amphibians eat insect vectors.

We can help reduce the risk of zoonotic disease by protecting our natural ecosystems. This can be done in various ways.

Many organizations around the world have dedicated their resources to address biodiversity loss including; UNEP's Convention on Biological Diversity, the International Institute for Environment and Development, Millennium Ecosystem Assessment, World Wildlife Fund, and E.O. Wilson Biodiversity Foundation (to name a few).¹⁹ However, these organizations can't tackle this issue alone and it will depend on all of us to reduce biodiversity loss. Together, we can help minimize the risk of infectious diseases in the future while protecting our vulnerable environment.