If you’ve been following climate news for a while, you’ve probably heard the term biodiversity before. This umbrella term covers an incredibly expansive, diverse and awe-inspiring collection of living organisms, which can sometimes be hard to visualise under such a simple scientific name.
In the wake of the ongoing climate strikes, where biodiversity loss has been highlighted as a huge problem, I thought now would be a good time to explore and explain what biodiversity actually is, why it’s so important, and what we can do to protect it.
What is biodiversity?
Without biodiversity, there is no future for humanity
The word biodiversity was first coined in 1985 as a contraction of the phrase ‘biological diversity’, a term created by Dr. Thomas Lovejoy, a conservation and tropical biologist who has conducted research in the Amazon since 1965.
Put simply, biodiversity is an umbrella term that encompasses the entirety of the approximately 9 million+ unique living species on our planet and how they interact with each other. It includes plants, animals, microorganisms such as bacteria and viruses, and biological units known as biomes (a specific geographic area notable for the species living there), as well as the diversity of genetic information within each species, the variety of ecosystems they make up, and the way they continually evolve to remain functioning and adapting to their environment.
Types of Biodiversity
Biodiversity can be broken down into three categories: genetic diversity, species diversity and ecosystem diversity. These three work in harmony, forming functioning systems that perfectly support each living organism within them. Here’s what they encompass.
This refers to the variety of genes within a species, as each individual living being has a unique genetic composition. This means a species may have different populations, each with different genetic makeup. Different populations of a species have to be protected, therefore, in order to preserve genetic diversity.
Different species have different amounts of genetic diversity. More recent evolutionary lines, such as kangaroos, have less genetic diversity than those descending from ancient lines. Genetic diversity is particularly interesting because a species’ potential ability to adapt to changing environments or new diseases relies on a foundation of genetic diversity.
Additionally, more recent work on genetic diversity has suggested that creatures once thought to be a single species could be multiple species, suggesting that that the number of distinct living organisms on our planet is much higher than we can accurately estimate. A single spoonful of soil, for example, contains 10,000 to 50,000 different types of bacteria.
This refers to the variety of species within a habitat. For example, rainforests contain many species while other habitats, such as a polluted lake, will contain fewer species.
Naming and counting species is incredibly important. Biologists first determine an organism’s unique characteristics and whether or not it belongs to any other described species, which then allows them to investigate questions about its biology. The research that follows leads to the discoveries that make the species valuable to humans and the wider world. Giving a species a name and description allows multiple scientists to study it in-depth in a coordinated way.
17,000–20,000 new species are logged each year. Plants comprise 82% of the total biomass of the planet, while invertebrates make up about 97% of all animal species. Most of these are insects, who are invaluable as pollinators. Mammals make up less than 1% of all animal species. Humans, an even smaller number.
This refers to the diversity of ecosystems in a specific place. An ecosystem is a community of organisms and their physical environment, interacting with one another. Ecosystems can be large, like a coral reef, or small, like a pond.
The loss of an ecosystem means the loss of the interactions between species and the loss of biological productivity that an ecosystem is able to create. Ultimately, these losses hurt everyone else too.
Biodiversity across the world
About 1.7 million species of animals, plants and fungi have been recorded, but estimates on the total existing number of species rise as high as 100 million.
Biodiversity is also not evenly spread across the globe. For example, 15 hectares of Borneo forest contains 700 tree species, which is the same amount as the whole of North America. Many places, especially rainforest areas, contain endemic species, which are found in only one location. These species are especially vulnerable to extinction and, if their habitats are destroyed, they are lost for good.
The study of the distribution of current and past species is known as biogeography. This work is important to understanding the world around us, how environments affect the species within them, and how changes in environment can impact the distributions of a species.
Why is biodiversity important?
Some answers are clear: plants create oxygen, insects pollinate and allow food to grow. Others are more hidden: greenbeds such as reefs and forests protect coastal communities from cyclones and tsunamis, plant respiration creates clouds (read more on why clouds matter here), hardwood trees that remove CO2 from the air rely on their seeds being dispersed by tropical tortoises and spider monkeys.
We may think we understand everything going on in an ecosystem, but look beyond the obvious and there are innumerable interactions between all living organisms, creating healthy systems that leave no waste, clean our air and water, and provide all beings with food and liveable climates. These systems are perfectly in tune with each other, honed over millions of years, to create life cycles that support everything within. Humans rely on these cycles to survive too, though sometimes this can be forgotten.
If we want to take a human perspective, however, the services provided by ecosystems are estimated to be worth double the world’s GDP. Ecosystem loss, therefore, also results in huge global financial losses. In Europe alone, biodiversity loss costs the continent about 3% of its GDP, or €450m every year.
Biodiversity is also vital to the continuing development of medicine. Many significant medicines are derived from natural chemicals, for example aspirin, codeine, morphine, digoxin, atropine, and vincristine, while antibiotics are often produced by fungi and bacteria. Additionally, venoms from many animals are researched for medicinal use too, for example snake venom has been studied for cancer treatment. If we lose biodiversity before we have the chance to study it, we lose many potential life-saving innovations in the future.
Why is biodiversity under threat?
The term biodiversity loss describes decreased biodiversity due to displacement or extinction of species. A recent study from over 550 researchers emphasised something you may have heard a lot recently: that we are in the sixth mass global extinction. The current accelerated rate of extinction is estimated at 1,000 times the normal rate, meaning that tens of thousands of species will be lost during our lifetimes. Much of this loss occurs in tropical areas, such as the rainforest, which contain high levels of endemic biodiversity that is destroyed for timber and agriculture. 99% of currently threatened species are at risk because of human activities, and many species that will be lost will not have even been discovered before they disappear.
Other factors of biodiversity loss include pollution, which often harms marine animals, globalisation, as animals such as frogs are exposed to fungal diseases spread by the exotic pet trade and invasive species are accidentally transported to new habitats by humans. Alongside the rainforest, waterways like rivers and lakes are hit particularly hard. Freshwater animal populations have decreased by 81% since 1970, mainly caused by water extraction, pollution, and dam building.
As ecosystems collapse, many species and overall systems in which they work together are lost. Ultimately, this impacts humanity on a large scale too. Like every other species, we rely on various ecosystems to provide things like healthy soil to grow food and oxygen to breathe. As we lose biodiversity, we lose the stability and productivity of these ecosystems, meaning we also lose reliable access to food, water, air and resources. Beyond this, destroying biodiversity before we’ve even had the chance to understand and study it gives us less chance of discovering new medicines and understandings of our world that can help human life around the globe.
In general, humans are less likely to understand how much we rely on nature because many of us have grown up in societies where humans are vastly disconnected from it; instead dramatically modifying the world around us for things like agriculture. Many people (predominantly white westerners from colonising countries) see the natural world as a wealth of resources to be extracted and exploited, not a series of interconnected webs that we are also part of, and that we desperately need in order to survive as a species. After all, the earth will live on long after humanity is gone.
What needs to change to protect biodiversity?
Firstly, our perspectives. Aside from Indigenous communities, who live in harmony with the ecosystems around them, humanity needs to move away from colonial, profit-based thinking and towards awe and understanding of just how incredible biodiversity is, how vital it is to our survival, and how we must live in balance with it. To do this, we can work on increasing our nature relatedness, learning more about the earth around us and investigating systems such as seasonal eating and rewilding. We can look intro regeneration and building back soil, restoring vegetation to waterways, and upping biodiversity in the areas we live in.
Additionally, we need to shift our thinking away from singular animals. Biodiversity is conserved best when we focus on saving habitats and ecosystems, not specific species. Conservation campaigns focusing singularly on one animal miss the point, as these animals don’t exist in a vacuum. If a species is at risk, its habitat and ecosystem is likely to be under threat too. In order to save the one, we need to work to save the whole.
Ecosystem regeneration, while also improving and protecting biodiversity, takes carbon out of the atmosphere, and could provide up to one-third of the climate mitigation we need. Regeneration and natural solutions need to become our top priority. Not only will this save countless species, it will ultimately save us too.
Particularly good examples of this include Costa Rica. Over 30% of Costa Rica is marked for conservation, and it is the first tropical country to have reversed deforestation. Over half of its land is covered by forest, compared to 26% in 1983. Additionally, the country implements an ecosystem services law, which taxes gasoline and uses the revenue for reforestation.
Another strong example is the Great Green Wall in Africa. When completed it will be three times the size of the Great Barrier Reef, making it the world’s largest living structure. It will also regenerate 50 million hectares of land, provide food and water security for 20 million people, create 350,000 jobs, and sequester 250 million tons of carbon. Additionally, it provides opportunities for countries to reintroduce indigenous fauna, increasing biodiversity in the plants that comprise the wall and the organisms that inhabit these newly planted ecosystems, including microbes in the soil.
80% of the most biodiverse areas on Earth are home to Indigenous and tribal peoples; people who already live in harmony with the land and who have developed effective methods for maintaining the richness of their environment and preserving biodiversity. Supporting Indigenous sovereignty through respecting land rights and legal rights inherently protects biodiversity by avoiding colonial conservation practices. By restoring rights to Indigenous people they are able to continue to protect the land, ecosystems and species that they cohabit with.
Here I am again, talking about ecocide law. But agricultural, logging and mining companies that encroach on Indigenous lands and destroy habitats to create monocultures over ecosystems (or destroy the land altogether) are huge contributors to biodiversity loss. Making this illegal across the globe is a way to both prevent future loss and hold those accountable who have created these issues.
To learn more:
Plus, here are some recommendations from The Guardian:
The Biological Diversity Crisis (1985). Edward O Wilson. BioScience (Vol 35)
The Sixth Extinction: An Unnatural History (2014). Elizabeth Kolbert (Bloomsbury)
What Has Nature Ever Done for Us? (2013) Tony Juniper (Profile)
The Economics of Ecosystems and Biodiversity (2010). Pushpam Kumar et al. (Earthscan)