Biodiversity is a word that gets tossed around a fair amount in discussions about the environment. Generally, it is defined as the variety of different species and organisms living in an environment, but there is more to it than just this definition. Biodiversity is an extremely complex ecological relationship that allows habitats to function. It can be broken down into three subcategories: genetic diversity, species diversity, and ecological diversity.(1) Each of these subcategories takes a deeper look into how biodiversity works.
Genetic diversity is the variety of genetic makeup within a species. This mainly occurs due to environmental adaptation; over time animals acquire certain traits that allow them to better survive in their environment. For example, moths have different coloured wings. These help them blend into their environment, so their colour and pattern vary by location. Humans can also breed certain genetic makeups to create diversity within a species. For example, dairy cows are typically thinner than beef cattle. They are the same species, but bred for different purposes. Beef cows are meant to be stocky and large, providing more meat, while dairy cows are bred to produce milk.
Species diversity goes a little broader, looking at the variety of different plant and animal species within a habitat. This directly affects how the ecosystem operates—from the food chain to interactions between wildlife within the ecosystem. Species diversity allows there to be a balance within an environment, as each species plays a different role that allows an ecosystem to bloom. For example, plants create oxygen with photosynthesis and grazing animals keep vegetation in check.
Species diversity also creates balance by driving competition for resources like food and territory.(2) This can be seen in the predator and prey ration. Predators have the important role of keeping overpopulation in check to prevent overgrazing, but when prey numbers decline, the shortage of food will also keep the predator ratio at a healthy level. Humans need to be aware of this ratio, as tipping the ratio too far in either direction can have dire consequences. Too many predators and there won’t be enough food. Too many prey animals and the predators won’t be able to keep the overpopulation under control. This can lead to extinction of certain plant and animal species, hurting the balance of the ecosystem.
Ecological diversity is the widest umbrella, including interaction amongst all organisms in a given ecosystem. It defines how every species within an ecosystem interact amongst themselves, others, and their environment. Everything within a habitat contributes something to the cycle of life. Ecosystems are made up of plant, animal, and micro-organism communities that all accumulate to maintaining the habitat.(3) The interactions between these communities are what make an ecosystem thrive, as every little role an organism plays contributes to the bigger picture.
The circle of life is an example of these interactions: herbivores consume plants, predators hunt the herbivores, and then the predators eventually die and are decomposed by organisms, like fungus, that turn decay into nutrients for vegetation to grow again. Without every organism doing its job, the ecosystem’s condition would decline.
Humans have a role to play in maintaining biodiversity as well. Whenever humans interact or make large changes to a habitat, it can upset the balance of biodiversity in that ecosystem. This can be almost any action, from carbon emissions to building infrastructure. Every action can have an impact; even plastic straws that end up in the ocean can be swallowed or inhaled by sea life, which is why the agri-food industry started the widespread switch to paper straws over the last few years. As the curators of this planet, showing diligence towards mitigating climate change and resolving environmental issues can maintain biodiversity and created a better future for all.
1. North Carolina Association for Biomedical Research—Biodiversity
2. Nature Education—The Maintenance of Species Diversity, 2010
3. Coastal Wiki—Ecosystem Diversity