David Attenborough, while still known as a national treasure and nature programme presenter, is more recently getting a repuation as a hard-hitting documentarian. 

The 94-year-old's latest TV offerings have had a tendency to bring people to tears for their devastating footage of animals battling for survival against the odds — particularly in terms of the impact humans are having on the natural world. 

But his latest documentary, BBC One’s Extinction: The Facts, which aired on Sept. 13, goes one step further — delivering an important message to viewers about exactly why species extinction should be so concerning for human welfare too.

So who is watching? Who is listening? Who will act? #DavidAttenborough#extinction@BBC
1 million species threatened by 1 species of over 7 billion individuals.#conservationoptimism ? pic.twitter.com/mfvJTt0aAw

— Stephen Woollard (@ZooStephen) September 13, 2020

Here are some of the important things we learned from Sir David about how species extinction undermines human progress, leading to greater risk of disease, hunger, and poverty, among other alarming issues — plus some of the ways this dire situation can be turned around. 

1. Biodiversity loss can lead to pandemics

Attenborough and a host of experts on the programme explained how the loss of biodiversity makes the likelihood of pandemics — like the one we’re living through right now — more likely.  “Scientists have linked our destructive relationship with nature with the emergence of COVID-19,” Attenborough says. 

And new diseases don’t only spring from the live animal markets blamed at the start of COVID-19, either.

The level that humans have encroached on natural habitats is a factor too. In fact 31% of emerging diseases have originated from land use change, the programme revealed.

One example of this is in clearing rainforests in order to use the land for cattle farming — when, in fact, this creates a risk of previously unknown viruses then coming into contact with people and cattle.

A related issue is habitat loss, meaning the homes of nature’s predators and larger herbivores are disappearing.

Disease-carrying smaller mammals, like rodents and bats, are the “big winners” from this disappearance of larger animals, says Prof. Felicia Keesing, a disease ecologist. As the larger predators disappear, their populations are not being kept in check.

This means, she adds, we’re creating a situation which vastly increases the numbers of animals more likely to spread disease. 

2. Insects are essential  

“Soil should be teeming with life,” says Prof. Richard Bardgett, a soil ecologist from the University of Manchester, on the show. “But reports have suggested that up to 30% of the land’s surface globally has been degraded.” 

Bardgett explains that insects in the soil provide a crucial function — they break down organic matter so that the soil is ready for plant growth.

Without these vital insects — which are being lost at an alarming rate — harvests are affected, impacting people all over the world.

It’s particularly the poorest people in developing countries who will suffer food shortages, but everyone, everywhere will be impacted, points out Sir Robert Watson, a chemist who is also chair of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. 

3. Plants are at risk 

Kathy Willis, a plant scientist from the University of Oxford, highlighted that one in four of the plants assessed in the UN’s 2019 global study of biodiversity are at risk of extinction. “I find that terrifying,” she said, explaining that plants are so crucial to our food, water, and air quality. 

“Trees regulate the water flow across landscapes… so you chop all those trees down, there’s nothing doing that, you end up with a landslide,” Willis explains. “We’ve made that mistake many, many times.” 

Even in the UK, with its mild climate, floods have increased as marshy wetlands that could absorb rain water have disappeared, the show revealed. 

4. The illegal animal trade is sky-rocketing

In the past 20 years, poaching and the illegal wildlife trade has become a multi-billion dollar industry, Attenborough said.

The most traded animal isn’t one you might immediately think of either — it’s the pangolin, a mammal covered in scales that lives off ants.

“Traders claim they have medicinal purposes,” said Iris Ho, a wildlife specialist at the Humane Society International. “But pangolin scales are just made from keratin, like our fingernails.”

The numbers killed are increasing — It’s estimated that over 175,000 pangolins were killed for their scales in 2019 alone, the programme revealed. 

5. Overfishing is a serious issue

Trawlers with nets bigger than houses roam the oceans, hauling up everything that gets caught up in them, Attenborough narrates. He adds there’s an estimated 100,000 trawlers at work at any one time. 

The waters around major fishing countries — such as China, Indonesia, and the US — are being emptied, and the populations aren’t recovering, explained Prof. Daniel Pauly, from the Institute of Oceans and Fisheries at the University of British Columbia, in Canada.

“We’ve found that in China, the waters have about 16% left of what we had [in fish levels] 120 years ago,” said Pauly. Similarly, he added, in the waters around Britain, there is only 5% of trawler cod fish left compared to the turn of the 20th century. 

6. Consumption matters

While population growth is happening much more rapidly in developing countries, pressure on resources is coming from developed countries, Attenborough explained.

He added that the average Briton consumes four times more resources than the average person living in India. How products are made, the ways the production damages the environment in the process, and the rate these products are made has an impact.

Thinking about how we use resources, and managing them sustainably is key. Watson, who led the UN’s 2019 study on biodiversity loss, said that we waste 40% of the food we produce.

“If we could reduce that food waste, it would go a long way to making a more sustainable agricultural system,” he added. 

7. We can change

The experts on the programme offer hope for the future — but it will take work from all of us. 

“The world has been on pause during the pandemic, and as we begin to move forward, we have a moment to change the way we’re running our world,” continued Keesing. 

Governments investing in “green jobs” such as installing renewable energy sources like solar panels, while strengthening environmental protection laws and investigating global supply chains, will have an impact. 

While we as individuals can think more carefully about our own consumption — thinking about what we’re buying and where from — will make a difference in the long run too, said Willis. 

Attenborough concluded: “One thing we do know is that if nature is given the chance, it can bounce back."

You can stil watch Extinction: The Facts on BBC iPlayer in the UK.