What, exactly, is wild?

Unconstrained. Independent. Unpredictable. Wild!

We all have an intuitive sense for what wild means. Some of us shy away from the wild, while others gravitate toward it. Regardless, most of us get some satisfaction from knowing that somewhere out there, usually elsewhere, is still wild.

But what, exactly, is wild? Where is the line that separates the wild from the tame?

An albatross circling the Southern Ocean is clearly wild. What about a house mouse stealing scraps from a kitchen? Or the worker honeybees born in a commercial hive? What about a century old native tree originally planted in a reserve? Or its offspring? What about the non-human microbes that make up over half the cells in my body? Am I half wild?

One Oxford Dictionary definition of wild is

an “animal or plant” “living or growing in the natural environment” and “not domesticated or cultivated”.

As a biologist, I have some issues with this definition. For a start, it omits fungi and microbes, although that’s a common oversight. Bigger problems are wrapped up in “animal” and “natural environment”.

I take issue with the antiquated notions of “humans and animals” and “people and nature”, as if we are somehow not animals and not part of nature. We’re amazing animals, the likes of which the world has never seen before, but we are still very much animals. Homo sapiens is a primate species in Kingdom Animalia and every species in Kingdom Animalia is, by definition, by biology, and by ancestry, an animal.

We are also animals that are still part of and completely dependent on the rest of the natural world. We depend on other species to clean our water, make the air we breath, recycle our organic waste, feed us, make the soil, and control most of our pests and diseases. Everything alive on Earth, and everything that life does and makes, is part of Earth’s natural environment. That includes us.

So, I am definitely, and without any doubt, an animal in my natural environment.

Does that mean that I am wild? No. The intent of the concept “wild” is something apart from us. When we say “wild”, we don’t mean ourselves. We also don’t mean a cow in a pasture or a potato in a field. Our domesticated animals and crop plants are an extension of us. Wild is supposed to be the something else.

What does it mean to be a part of nature that is not us? This gets us to the last part of the definition from the Oxford Dictionary, that wild things are not cultivated or domesticated. If I collect wild seed from a forest and plant it in my garden, it loses its wild. It’s been cultivated. It grows where it grows because of me. Similarly, a cow is a domesticated animal, bred and fed by us. It is not wild.

Defining wild as not domesticated raises the issue of when, exactly, an individual animal should be called domesticated. The definition of domesticated animals is that they are tamed animals kept as a pet or on a farm. However, honey bees in a commercial bee hive are animals but they aren’t exactly tamed and then neither are they wild. Similarly, if I catch a mouse and keep it in a cage and feed it, it’s not suddenly tamed, but then neither is it wild anymore.

I think it’s clearer to define a wild organism differently. Here is what I suggest.

wild organism: an organism that people do not purposefully reproduce, disperse, or restrain.

Domesticated and cultivated organisms are all purposefully reproduced and/or dispersed by people, and so not wild. Animals that we catch and bring into captivity are purposefully restrained by us, and so not wild.

The inclusion of purpose is important here, as a lot of wild species, especially pests and weeds, are experts at dispersing by hitchhiking on our vehicles or clothing. It is the purposeful management by people that I see as drawing the line between wild and not.

With my definition, we can unambiguously define creatures as wild or not. Here are some examples, including the cases I posed earlier.

What about the non-human microbes that make up most of the cells in my body? That’s more complicated. Some colonies are clearly wild, being ephemeral or colonising me after birth. However, many other species have coevolved with humans and are with us from birth passed down from our mothers. I am inclined to include these as reproduced and dispersed and, essentially, restrained by us, and therefore not wild. In contrast, something like the common cold virus seems more closely analogous to the wild pests and weeds that affect our farms.

With the possible exception of our coevolved microbes, my definition draws a clear-cut line between wild and human managed organisms. It sets wild nature as the part of the biological world that is not us, while the species we grow are part of us (part of our extended phenotype).

This clear definition of wild also lets us describe how many generations something has been wild, or has been removed from the wild. Seedlings are wild when their parent is a planted garden plant and they naturally dispersed to and germinated in a nearby nature reserve. These seedlings are first-generation wild, which will typically have less genetic, and ecological, integrity at a site than the multi-generation wild plants growing around them.

In general, populations of organisms that have been wild for hundreds of generations or more, will be more ecologically interesting, genetically diverse, and, for species with bigger brains, culturally more diverse. I also expect the old wild will generally contribute more to long-term to ecosystem functioning and ecosystem resilience.

The wild needs more attention, and more respect. More and more of the natural biological world, and its land and resources and energy flows, are becoming co-opted parts of humanity. We are losing wild, and that makes us all poorer.

Perhaps we’d allow more wild in our world if more of us acknowledged that we are animals, we are part of nature, and our actions determine the fates of our diverse wild companions.