Inheritors of the Earth, by Chris D Thomas

We are in the middle of the 6th great extinction event in the planet’s history, according to biologists and conservation agencies. It was in the news again last week, thanks to a new report that uses headline-grabbing phrases like ‘assaults on biodiversity’ and ‘biological annihilation’. And let’s not beat about the bush – we’ve seen how wildlife numbers have collapsed in recent years. There is a biodiversity crisis, and it is of our own making.

However, there is another side to the story, and it’s picked up in Chris D Thomas’ fascinating book Inheritors of the Earth: How nature is thriving in an age of extinction.

As you can tell from the title, Thomas doesn’t deny that there’s a problem – this is an age of extinction. But there are gains as well as losses, and we almost never talk about the gains.

Some species are doing very well out of human activity across the planet, and have reached a level of success that would have been impossible without us. New species are emerging as plants and animals hybridize in the wild. In many parts of the world biodiversity has increased as foreign species take hold, usually without displacing native varieties. Evolution itself has been given a big boost by all this intermingling, meaning that in the longer term, our destructive human era could be followed by an explosion of diversity – just as previous ages of extinction gave birth to new opportunities in the aftermath.

Unfortunately, we don’t see biological success stories for what they are, because we have a rather fixed view of what the world should be. We understand certain species to belong in certain places, and newcomers are considered invasive. “Too often, we act as if nature is an old master, a great painting that must be kept just as it is. When we perceive it to be blemished, we attempt to ‘restore’ it to some past state… To do so requires us to weed out those plants and animals that we think are in the wrong place. We kill successful species to protect unsuccessful ones.”

A large part of our problem is that we look at the world in a narrow time frame, thinking that what we remember as normal is the way things should be. But there is no one way the world ‘ought to be’. It has changed dramatically, with certain animals and plants in the ascendancy, and then swept away by disaster or climactic change. The last big reset came with the last ice age, and in Britain we lost several types of tree that couldn’t handle the cold. When tropical plants are brought in and they flourish, it could be seen as a kind of homecoming. “If you had taken a grand tour of Europe 3 million years ago, you would have encountered double the diversity of native trees.”

That begs the question – what is native? How long does a species have to be established in a country before we consider it to belong? Himalayan Balsam has been in Britain for 200 years and is considered invasive. The Tudors planted sycamores and a lot of people are still suspicious of them 500 years later. Sweet chestnuts were brought over by the Romans and are considered okay, so Thomas reckons that “two thousand years seems to be enough”.

The thing is, there’s nothing unnatural about humans introducing plants and animals to other parts of the world. Nature has always moved things around. Seeds stick to fur and feathers. Storms blow insects and birds to new territories. Floating wood carries bugs or lizards to new places. Human intervention has dramatically accelerated these movements, but we’re a part of the ecosystem. We belong here, and are therefore natural. Whether what we do is wise is another question, but “humans are simply acting as dispersal agents for other animals and plants – a completely natural process.”

If that sounds like an excuse to throw up our hands over climate change or extinctions, Thomas is having none of that. The book repeatedly insists that we’re not off the hook. But by looking at human actions in the broader context of evolutionary change, we can begin to think differently about nature and conservation. In particular, it opens up new approaches for conservation in the anthropocene. I’ll return to that another time, but as an example, we might decide that the best way to save a threatened species is to move it to a new location. We can relax about non-native species that do not threaten local ecosystems – which is most of them. We can re-introduce or even re-create lost species. We do not need to keep everything fixed, and we can adapt to change rather than try to prevent it.

Inheritors of the Earth is full of things that nobody else is saying, and the author shares his provocative thoughts with a clear passion for nature and a disarming enthusiasm for the subject. I would very much like him to be right. He might not be, and I’m still thinking about it. I’m going to pass the book on to my conservationist brother and discuss it with him, that’ll help.

If Chris D Thomas is right, it would not make conservation any less important. But it would make it more imaginative. As the rewilding movement has shown, there is a need for fresh thinking in the conservation world. What Thomas describes feels to me like a more mature approach, like humanity growing into the world we have created, and taking responsibility for our actions.

• You can pick up Inheritors of the Earth from Hive Books, Amazon UK or Amazon US.
• Feature image by Eli Francis