What is Biodiversity?

For many people living in towns and cities, wildlife is often just a documentary on TV. But the truth is that the air you breathe, the water you drink, and the food you eat ultimately depend on biodiversity. Without plants, there is no oxygen, and without bees to pollinate, there are no fruits or nuts. Coral reefs and mangrove swamps are essential for coastal communities, providing protection from tsunamis. Trees absorb air pollution in urban areas. While tropical tortoises and spider monkeys may seem to have little to do with maintaining a stable climate, the seeds of hardwood trees, which are the most effective at removing carbon dioxide from the atmosphere, are dispersed by these large fruit-eaters. The sheer richness of biodiversity has many human benefits. For example, many new drugs are being derived from nature, such as a fungus that grows on the fur of sloths and can fight cancer.

As scientists study these ecosystems, they discover countless interactions, all honed over millions of years of evolution. An intact ecosystem is a delicate balance that contributes vitally to a sustainable planet.

It’s mind-boggling! Around 1.7 million species of animals, plants and fungi have been recorded, but it’s only thought that there are 100 million species. The heart of biodiversity is the tropics. For example, there are 700 species of trees in 37 acres of Borneo Forest – the same number as the whole of North America. Recent studies looking at diversity at the genetic level have discovered that what was thought to be a single species can actually be dozens in some cases. Then when you add bacteria and viruses, the number of different organisms can be in the billions. A single spoonful of soil, which provides 90% of all food, contains between 10,000 and 50,000 different species of bacteria. Unfortunately, the biggest concern today is that many species are disappearing before we even realise they exist or the role they play in the life cycle.

In the last century, the number of tigers, which were hunted brutally, fell by 97%. In many parts of the planet, large animals have already been wiped out by humans, such as dodos and woolly mammoths… The “red list” prepared by the International Union for Conservation of Nature has assessed only 5% of known species. The data they found indicate that most species are threatened: 25% of mammals, 41% of amphibians and 13% of birds are at risk of extinction. New studies examine the massive and rapid decline of the world’s most widespread creatures. Unfortunately, the results are frightening; the number of animals living on the planet has halved since 1970. Academics describe this massive loss of wildlife as “biological annihilation”.

In Germany, 75% of flying insects have disappeared in the last 25 years – this massacre of biodiversity is causing a decrease in plant pollination and the depletion of the wild food chain. “If we lose insects the whole thing will collapse,” says Prof Dave Goulson of the University of Sussex.

As the human population grows, wildlife and farmland are cleared to make way for housing and industrial sites, and forests are cut down, biodiversity is declining. In 2016, 30 billion hectares were lost in the UK and Ireland.

As humans have become increasingly active on the planet, the balance of biodiversity has been increasingly disrupted through changing land use, overexploitation of resources and our impact on the climate. We are converting natural habitats into farms, factories, roads and cities. Another factor that is reducing biodiversity is poaching for food. We are overfishing, drilling and mining the ocean. Global shipping has also spread highly harmful invasive species around the planet, especially rats. Today, 300 species of mammals, from chimpanzees to hippos and bats, are at risk of extinction. Human-made pollution is a killer of orcas and dolphins. Whales are severely damaged by long-lived industrial pollutants. Global trade is causing more damage: the biggest decline in all animals due to a fungal disease thought to have spread worldwide through the pet trade. Of all these habitats, rivers and lakes may be the hardest hit; since 1970, freshwater animal populations have fallen by 81% due to pollution and dams.

Could biodiversity loss be a greater threat to humanity than climate change?

Yes. Even if it takes centuries or millennia, climate change can be reversed. But once species become extinct, it is irreversible.

Giving nature the space and protection it needs is the only answer. Protecting wildlife reserves is the solution. But the world currently protects 15% of land and 7% of oceans. Moreover, the human population is constantly increasing.

To give an extreme example, such as the poaching crisis for elephants and rhinos in Africa, one solution would be to make the animals more valuable dead than alive, such as by preventing hunting tourism. Or, one solution could be to compensate farmers for farm animals killed by predators.

In daily life, we all have a responsibility. Most wildlife is destroyed for the production of soy, palm oil, cattle, timber and leather. Most of us consume these products every day without even realizing it. Eating less meat, especially beef, which has a large environmental footprint, can help. In short, finding the tipping point that leads to biodiversity loss and ecological collapse is an urgent priority.

Invasive species are often introduced through human activities, either intentionally or accidentally. An example is rabbits, which were introduced to Australia by human colonists in the eighteenth century to be raised for food. Their population quickly exploded, and the large amount of plants they ate quickly led to famine.

Even today, rabbits in Australia are devastation of orchards and cause serious erosion problems by eating native plants. This is a major problem on islands where wildlife has evolved in isolation for millions of years and where ecosystems may be more vulnerable to the introduction of new animals and plants. Invasive species can reduce biodiversity and species richness, cause extinctions, and significantly alter ecosystems.

The good news is that it is within our power to change our actions to help ensure the survival of species and the health and integrity of ecological systems. By understanding the threats to biodiversity and how they arise within this context, we can manage conservation pathways. Conservation efforts over the past decades have made a significant difference to the state of biodiversity today. More than 100,000 protected areas, including national parks, wildlife refuges, game reserves and marine reserves managed by both governments and local communities, have provided a breath of fresh air for wildlife and have curbed deforestation. When habitat protection is not enough, other conservation actions, such as restoration, reintroduction and invasive species control, are beginning to show positive effects. All of these efforts have been supported by ongoing efforts to improve environmental policies at local, regional and global scales.

Finally, the lifestyle choices of individuals and communities can have a profound impact on biodiversity and the impacts on the environment. While we cannot prevent all negative human impacts on biodiversity, we can work to change the direction and form of our impacts on the rest of life on Earth.