Talking Trees

Fire, Humans and Trees

Subscriber Episode • • Arboricultural Academy • Season 2025 • Episode 145

Share episode

Subscriber-only episode

In this Thursday episode of Talking Trees, we take a long-view perspective on one of humanity’s most transformative relationships: the discovery and use of fire, and its complex connection with trees and the natural world.

We discuss:

  • How early hominins first encountered natural wildfires and slowly began to control and harness fire
  • The role of wood as fuel, and how fire shifted the dynamic between humans and trees—from forest dwellers to landscape shapers
  • The evolutionary implications of fire use, including the cooking hypothesis and its role in human brain development
  • The cultural and ecological legacy of fire—both as a tool for survival and a driver of deforestation and forest management
  • Why fire remains a double-edged force in arboriculture and landscape ecology today

From ancient hearths to controlled burns, this episode traces how fire not only changed humans, but also reshaped our relationship with trees.

Background information:

  • The discovery of fire by humans: a long and convoluted process | Philosophical Transactions of the Royal Society B: Biological Sciences.pdf


Send us a text

Buzzsprout


HeroHero



Arboricultural academy


Podcast is created using AI tools.

Roger:

Talking Trees with Lily and Jad. Welcome to Talking Trees, your gateway into the deep stories of our natural world. Today we journey back to a pivotal moment in human history the discovery and mastery of fire. Join us as we spark a conversation about the origins of fire and its enduring legacy in shaping humanity. Welcome to today's episode on Talking Trees.

Jad:

Welcome to today's deep dive, where we'll be exploring fire, but not just, you know, the immediate effects on trees, though we're going to be going way back to the beginning, looking at the long I mean, the complex relationship that we have with fire as humans and how that relationship has shaped both us and the environment that we share. And it's something that I think is, you know, especially relevant to professionals like yourselves, who understand that you know delicate balance of ecosystems and the power that fire has to both create and destroy.

Lilly:

It's a fascinating story, and one that's going to be especially relevant for you as arborists, who understand these processes so intimately.

Jad:

Exactly. And so, to guide us on this journey, we have a really interesting article called the Discovery of Fire by Humans A Long and Convoluted Process, and it was published in the Philosophical Transactions of the Royal Society B.

Lilly:

Right.

Jad:

And it's packed with insights about this evolutionary dance between humans and fire.

Lilly:

Yeah, this deep dive should uncover some surprising details about it.

Jad:

Yeah, and hopefully give you a fresh perspective on something that you may think For sure you already know a lot about.

Lilly:

Yeah, absolutely.

Jad:

Okay, so let's dig in.

Lilly:

Let's do it.

Jad:

First things first. It's important to remember that fire wasn't something that humans invented.

Lilly:

Right.

Jad:

It's a natural force that's been shaping landscapes for millions of years, long before humans even walked the earth.

Lilly:

Absolutely. I mean you just have to think about lightning strikes causing wildfires that sweep across savannas and forests. That sweep across savannas and forests. I mean these natural fires are all part of what we call fire regimes, which are patterns of fire frequency and intensity that shape ecosystems over time.

Jad:

Now you, as arborists I know, deal with fire regimes all the time.

Lilly:

Absolutely.

Jad:

But for our listeners who might not be as familiar, can you break down kind of what these different types of fire regimes are and how they actually influence forest ecosystems?

Lilly:

Yeah, sure thing. So you see, different ecosystems have evolved with different types of fire regimes are and how they actually influence forest ecosystems? Yeah, sure thing. So you see, different ecosystems have evolved with different types of fires.

Lilly:

Okay, some areas experience really frequent low intensity fires that clear out underbrush but don't really harm those mature trees. Others have these infrequent high intensity fires that completely reshape the landscape. These patterns, these fire regimes have a huge impact on which plants and animals can thrive in an area. For patterns, these fire regimes have a huge impact on which plants and animals can thrive in an area. For example, some tree species actually need fire to release their seeds or to create openings for their seedlings to grow.

Jad:

That's fascinating. So fire plays a role in the life cycle of the forest, and it's not just plants that are affected, right? The article mentions that animals have also learned to interact with fire in some pretty evicting ways.

Lilly:

Yeah, for sure. I mean. Some birds, for instance, are actually known to follow wildfires.

Jad:

Really.

Lilly:

They swoop in to catch insects and small animals that are fleeing the flames.

Jad:

Wow.

Lilly:

It's like this dramatic, you know, fiery buffet for them. Yeah, and even sure pansies have been observed foraging in recently burned areas, and even chimpanzees have been observed foraging in recently burned areas. They seem to understand that fire can reveal these hidden food sources.

Jad:

Okay. So if animals as different as birds and chimps are taking advantage of fire, it makes you wonder about you know our? Own ancestors right when early hominins drawn to fire for the same reasons, where they essentially fire foraging, as the article calls it.

Lilly:

It's a very compelling theory. I mean, picture this fire foraging as the article calls it. It's a very compelling theory. I mean picture this, you know. Picture our very distant relatives encountering a landscape that's been scorched by wildfire. They would have seen roasted insects, small animals forced out of hiding and cooked roots and tubers suddenly easier to access.

Jad:

Yeah, that makes a lot of sense, right. Fire would have made those resources more visible and probably easier to digest too. Exactly I can definitely see how early hominins would have been drawn to fire affected areas, even if they were still afraid of the flames themselves Of course. But when did we go from just forging around fire to actually controlling it ourselves?

Lilly:

Right.

Jad:

When did we start making fire rather than just finding it?

Lilly:

That's the million dollar question.

Jad:

Yeah.

Lilly:

And the evidence is really tricky to find. Archaeological sites seem to suggest that humans were regularly using fire by at least 400,000 years ago, maybe even earlier, but pinpointing exactly when we mastered making fire, that's a real challenge.

Jad:

Yep, but what's interesting is that this period around 400,000 years ago coincides with, you know, a major increase in brain size in the genus Homo. That's right. Do you think there's a connection there? In the article it mentions something called the cooking hypothesis.

Lilly:

Yeah.

Jad:

Could you explain what that is?

Lilly:

Yeah, the cooking hypothesis suggests that cooking food, which breaks down those complex molecules and makes nutrients more accessible, provided that extra energy that our ancestors needed to fuel larger brains. It's a bit like chipping wood right Smaller pieces are easier and faster to process, which leads to more efficient energy use.

Jad:

So cooking could be a key factor in what makes us well us.

Lilly:

It's possible.

Jad:

Our big brains, our ability to think and reason, all thanks to mastering fire.

Lilly:

It's a very intriguing theory and, of course, the debate continues.

Jad:

Yeah.

Lilly:

And there's evidence for and against it Of course. But what is undeniable is that cooking has played a huge role in shaping human cultures and diets.

Jad:

For a very long time For a very, very long time. Speaking of shaping fire's impact, it goes far beyond just food. It really does. The article highlights how essential fire has been for all kinds of technological advancements, from pottery to metalworking to, eventually, powering engines. That's right, and for you as arborists? I'm sure you've seen firsthand how these technologies have altered landscapes over time, haven't you?

Lilly:

Absolutely. I mean for anyone working with trees and forests you can't escape the impact of fire in these technologies.

Jad:

Thinking about that. Do you think that controlling fire, keeping it going, using it effectively, do you think that all of that actually helps shape human social structures too?

Lilly:

It's very likely. I mean, think about it. If you need to maintain a fire for warmth protection or cooking, you can't just leave it unattended. Someone needs to tend, to gather fuel, keep it safe. That requires coordination, communication, a shared understanding of how to manage this incredibly powerful force.

Jad:

It's almost like fire became a focal point for early human communities.

Lilly:

I think so.

Jad:

A source of warmth, light and social interaction.

Lilly:

I think so absolutely.

Jad:

And it probably even extended our days, creating what the article calls evening extension, giving us those precious hours after sunset to socialize, tell stories and maybe even develop language.

Lilly:

Exactly Imagine sitting around a fire, sharing stories and ideas as the flames dance.

Jad:

Yeah.

Lilly:

Those extended evenings made possible by fire could have been crucial for developing those complex communication skills.

Jad:

So fire, this force of nature, might have played a role in us becoming who we are today social creatures with big brain and the ability to communicate complex ideas. But, as we know, fire's impact on the environment is a double-edged sword, which leads us to a topic that's especially relevant for you as arborists.

Lilly:

And that's where things get even more interesting. Humans have undoubtedly altered natural fire regimes and, as you know, the consequences for ecosystems can be both positive and negative.

Jad:

Yeah, that's a great point and it leads us to you know the implications for you, our listeners, the arborists who are out there working to maintain the health and balance of you know, forests and trees.

Lilly:

How do these?

Jad:

changes in fire regimes, especially those caused by humans. How do they actually affect your work.

Lilly:

Well, understanding the history of fire in a particular ecosystem and how fire has shaped that ecosystem is really crewful for modern forestry and land management practices. Right, and this is especially true now with climate change adding yet another layer of complexity to the equation.

Jad:

Climate change is definitely intensifying fire regimes all over the world. Yes, we're seeing you know all over the world. Yes, we're seeing you know more frequent wildfires yeah. And they're burning hotter and spreading faster.

Lilly:

Exactly, and that's where the arborists come in. Your expertise in tree health, in forest management, in understanding how fire behaves, yeah, it's absolutely crucial for mitigating those risks and even, in some cases, harnessing the power of fire for good.

Jad:

Harnessing the power of fire. I have to admit that sounds a bit counterintuitive. Yeah, Most people think of fire as purely destructive.

Lilly:

Right.

Jad:

How can fire be a force for good in a forest? It's all about balance, okay.

Lilly:

Think of it like is fire can be destructive, yes, but it can also be this force of renewal and revitalization. Okay, think of the concept of pyrodiversity.

Jad:

Okay, pyrodiversity, that's a new word for me. What does that mean exactly?

Lilly:

Pyrodiversity refers to the essential role that fire plays in maintaining biodiversity. It's the idea that fire, when managed correctly, can actually increase the variety of plant and animal life in a forest. Wow Okay, for example, controlled burns.

Jad:

Right.

Lilly:

Which I know you, as arborists are very familiar with, can clear out dense underbrush and allow sunlight to reach that forest floor.

Jad:

Right.

Lilly:

This can create the conditions for a wider variety of plants to grow, which in turn, supports a greater diversity of insects, birds and other wildlife.

Jad:

So fire can actually help create a healthier ecosystem. It can. That's fascinating, and I bet this concept of pyrodiversity is particularly relevant to you as arborists.

Lilly:

It is.

Jad:

How do you think about pyrodiversity when making decisions about, you know, controlled burns or other forest management practices?

Lilly:

It's definitely a crucial consideration. For example, when planning a controlled burn, we have to think about the types of plants and animals that are present in that area.

Jad:

Right.

Lilly:

And how they will be affected by the fire. We want to make sure that the burn will benefit the overall biodiversity of the ecosystem.

Jad:

So it's about finding that sweet spot right.

Lilly:

Exactly.

Jad:

Using fire in a way that promotes a healthy and diverse forest and controlled burns aren't just about promoting diversity, are they?

Lilly:

No, they're not.

Jad:

They can also be an important tool for controlling invasive species.

Lilly:

Absolutely Invasive species often thrive in environments where fire has been suppressed for long periods, outcompete native plants and can create these monocultures that are more vulnerable to disease and pests.

Jad:

Right.

Lilly:

By reintroducing fire into these areas, we can create conditions that favor native species and help to restore the natural balance of the ecosystem.

Jad:

It's almost like hitting a reset button.

Lilly:

It is.

Jad:

Giving the native species a chance to thrive again, and that ties into the work that you all, as arborists, do every day doesn't it, it does. Making those decisions about which trees to prune, which areas to thin, how to manage the overall health and resilience of a forest.

Lilly:

Exactly, and with climate change intensifying these fire regimes, these decisions are becoming even more complex and even more crucial. Arborists are truly on the front lines of this challenge, using their expertise to help forests adapt and thrive.

Jad:

We've been talking about the power of fire and its impact on human evolution and how it shapes the ecosystems we depend on. But now, as we kind of wrap up this deep dive, I think it's important to consider the ethical dimension of using fire as a tool, especially in the context of how human activities have altered, you know, natural fire regimes.

Lilly:

Yeah, that's a really crucial point. It's not just about understanding the science of fire, it's also about understanding our responsibility to use this powerful force wisely and ethically Right.

Jad:

And it's a complex issue with no easy answers. For centuries, we've suppressed fire in many parts of the world, believing it to be purely destructive and, as we've discussed, this has led to the buildup of fuel and forests making them more susceptible to these catastrophic wildfire that we're seeing more and more often in forests, making them more susceptible to these catastrophic wildfire that we're seeing more and more often.

Lilly:

Exactly so now we're faced with this real dilemma Do we continue to suppress fire, risking even larger and more destructive wildfires in the future, or do we embrace fire as a tool, using it to restore balance to fire-adopted ecosystems? But even if we choose the latter, how do we do that ethically? How do we make sure that we're not causing more harm than good?

Jad:

That's the heart of the matter. We need to acknowledge that our actions, even those with good intentions, you know, have consequences and we need to proceed with a lot of caution and respect for the natural world. It's like you were saying before about learning from indigenous communities who have been managing fire for generations.

Lilly:

Right.

Jad:

Their traditional knowledge and practices can offer valuable guidance as we try to navigate these complex issues.

Lilly:

Absolutely. They've learned to live with fire, to understand its rhythms and its power. We can learn so much from their deep connection to the land and their long experience with fire management.

Jad:

And we need to combine that traditional wisdom with modern scientific research right. We need to understand the ecological impacts of fire, both the short-term and the long-term effects, so we can make informed decisions about how and when to use fire as a tool.

Lilly:

That's right. It's a balancing act, finding that sweet spot where we can use fire to promote healthy ecosystems without causing unintended harm. And for you, as arborists, this is especially important. You're the ones out there on the front lines making decisions every day about how to manage forests in a world that's increasingly impacted by fire.

Jad:

And with climate change intensifying those fire regimes, those decisions are only going to become more challenging, absolutely, but also more important.

Lilly:

Your expertise is invaluable. You understand the intricate relationships between trees and fire and the environment. You have the knowledge and the skills to help guide us toward a more sustainable and fire resilient future.

Jad:

So, as we wrap up this deep dive into the world of fire, I want to leave our listeners with a few key thoughts. First, remember that fire is a powerful force, both destructive and creative. Respect the power learned from its history and use your knowledge wisely.

Lilly:

Second, engage with your communities, share your expertise, work together to develop ethical and effective fire management strategies that consider the needs of both people and the environment.

Jad:

And finally, never stop learning. The world of fire is complex and ever-changing. Stay curious, stay engaged and keep deepening your understanding of this essential element.

Lilly:

Because the future of our forests, and indeed our planet, depends on it.

Jad:

Well said. Thanks for joining us on this journey. Until next time, stay curious and keep those embers burning.

Roger:

Thank you for joining us on today's journey into the origins of fire and its profound impact on humanity. As we explored how early humans transformed opportunistic encounters with natural fires into a cornerstone of civilization, reshaping our diets, social bonds and technological progress, we're reminded that each spark from our past lights the way for future discoveries. Until next time, keep the flame of curiosity alive. On Talking Trees, you.

People on this episode

Head Shot

Jaroslav Kolařík

Producer
Head Shot

Denisa Grábner

Editor
Head Shot

Josef Grábner

Editor

Podcasts we love

Check out these other fine podcasts recommended by us, not an algorithm.

Arboristika aktuálně Artwork

Arboristika aktuálně

ČSOP - Arboristická akademie
ArboChat Artwork

ArboChat

ČSOP - Arboristická Akademie