Saving biodiversity: why our mental and physical health depends on it

During the COVID-19 lockdowns, more of us are noticing the variety of animals, trees, and flowers in our back gardens or local park - and how being in contact with nature can influence our happiness.

This variety of life is known as biodiversity and it’s essential for our health and wellbeing. We depend on biodiversity in the natural world for the water we drink, the food we eat and the clean air we breathe.

But reports show that it is declining at an unprecedented rate – and that this is likely to lead to huge economic and health risks. For example, farming relies on bees and butterflies to pollinate plants, which create fruits and vegetables. Losing pollinators will cost the UK agricultural sector up to £700 million each year, and would seriously affect the country’s food supply.

Our new research study looks at the various ways plants, animals, insects and the bacteria around us can, indirectly, be beneficial to human health (and how in some instances they can actually be harmful). Below are the four main takeaways from our research.

1. Biodiversity is vital to our survival

Nearly 75% of all approved medical drugs come from nature and we rely on the biodiversity of plants and animals to find new medicines. To date only a small fraction of plants, animals and microbial organisms have been studied for their medicinal properties – meaning there could be a huge wealth of untapped potential out there.

But it isn’t just drugs and medicine, all the food we eat comes from the biological diversity of animals and plants — and the work of bees and butterflies that pollinate those plants. Much of the world’s fresh water is provided from forests. The diversity of organisms in forests also clean and filter water.

Biodiversity can also help human health by reducing extreme heat. Urban green space with a high diversity of trees can stop cities from becoming too hot.

2. It also helps us recharge

The pressures of daily life can stretch our ability to handle stress, focus our attention and solve problems, which puts us at risk of being stressed and mentally ill. But research has shown that biodiverse environments can help us recharge. For example, people living in neighbourhoods with more birds report being less stressed. And a study which involved stressed people looking at meadows featuring a variety of plants found that people were most relaxed when looking at meadows with at least 32 different species of plants, compared to just one species. Another study, looked at the views people have from their houses and found that those with views of lots of different plants, shrubs and trees had significantly lower levels of cortisol – one of the main stress hormones.

3. It offers us a sense of perspective

Sights and sounds of diversity in nature – such as seeing hundreds of seabirds in flight or being in a forest – inspire strong emotions of awe, amazement and wonder. And these experiences can give us a sense of perspective and help us to reflect on our own life goals.

Research has found that people feel more able to reflect and gain perspective on life when in a green space with a high species richness of plants and birds.

Biodiversity can also help to encourage us to live healthier lifestyles. A study in the US, for example, found that people reported doing less outdoor exercise in areas that had lost ash trees, compared to areas with ash trees. Ash trees are common in yards and along streets in the US and parts of Canada, but they are being destroyed by an invasive species – a beetle called the Emerald Ash Borer – which is native to China, Japan, Taiwan, Korea and Mongolia.

4. Habitat loss and the wildlife trade threaten this

That said, biodiversity also has the potential to harm us. Seasonal allergies, stinging nettles, ticks and viruses are all examples of the harmful side of the natural world. But more of a concern is the fact that unsustainable management of biodiversity, through habitat loss or the wildlife trade, can increase the risk of interactions with animals that carry infectious diseases - and make future pandemics more likely. This shows the need for sustainable management of biodiversity – by preserving ecosystems or stopping illegal trade in wildlife.

Given, then, that one million species are at risk of going extinct and the negative impact that biodiversity loss has on human wellbeing and health, it’s clear that action is required now. This is important because biodiversity loss is a global issue - and for real change to occur, solutions needs to implemented on a national and global scale.