Halloween, and why you should love creepy creatures
This week, during the spookiest time of the year, we’re going to look at the unfair portrayal that certain organisms get due to their reputation of being scary, dangerous, or gross, just like the ones above my head now. Instead, we will talk about what makes them great for both the planet and ourselves, as well as what we can do to protect them.
In this episode
01:04 - Why do we find certain organisms scary?
Why do we find certain organisms scary?
Adrienne Mayor, Stanford University
In this most hallowed time of the year, many of us look forward to going out, seeing images of witches, ghosts, and ghouls, and getting a good fright. But a few poor organisms got caught up in this negative press somewhere along the way, and are now stuck with a bad rap. Well that’s what this show is hoping to remedy, as we extol the virtues of so-called ‘creepy creatures’ and ‘frightening fungi’. But before any of that, how did we get here? Why did certain animals become attached to Halloween, and how far back does it go? Adrienne Mayor is a historian at Stanford University, and author of ‘Flying Snakes and Griffin Claws’.
Adrienne - Certain animals are synonymous with Halloween for starters, because they're nocturnal and predatory. These creatures engage in mysterious activities in the dark, and so they've been cloaked in superstitions since ancient times. And the combination of dark grey, brown or black colours with their sort of cryptic, mysterious nighttime habits, that kind of brings a sense of fear and awe. Especially if you think back in history when the only lights at night were oil lamps and wax candles. If you just think about how dark and long the nights were for people before electricity, it's easy to imagine how frightening the creatures of the night might be, especially if you knew or could sense that they were maybe lurking just beyond that flickering light of a fire or a candle flame.
Will - I'd never thought about the colour scheme being scary, but that's a very good point because you don't have a scary bluejay, do you?
Adrienne - Not really. No. <laugh>.
Will - I guess that makes sense. From almost an evolutionary defence mechanism standpoint, if something is predatory and nocturnal, you don't want to be anywhere near that.
Adrienne - Yes, we have an evolutionary benefit in being frightened of such creatures. We need to be able to feel terror and react to them. We do seem to be sort of hardwired to be afraid of or repelled by certain distinctive features of dangerous predators or poisonous animals because they were, they were real genuine threats to our survival for most of human history, stealthy hunters in the night, they preyed on early humans. So we learned to fear predators with certain features of big eyes, large claws and talons, ferocious teeth. I think we did evolve to be afraid of these creatures.
Will - Obviously evolving to be afraid of creatures like this means that it sort of goes back further than we could ever measure it because it is sort of a primal instinct. But is there a time where these sorts of organisms got drawn into folklore, into scripture as it were?
Adrienne - I think we can go back to ancient Greece and Rome, and especially Rome, I think because the Romans had all these superstitions and omens, and they're all always looking for signs in nature that would warn them about bad things that were about to happen. And of course, the Romans came to Europe and even Northern Europe and England, and so they brought a lot of those superstitions.
Will - That's an excellent point, that it's almost like humans evolve to be so good at pattern recognition that as soon as they see something strange in nature happen at the same time as something they don't like, it must be related, right?
Adrienne - Oh, I think that the basis of superstition is causality. I mean, even if you're not superstitious, you think to yourself, 'well, it couldn't hurt' <laugh>.
Will - You've touched on there the idea of creatures with talons and teeth and stuff that you'd do well to stay away from, but there's also organisms like fungus and worms, which are, let's be honest, not quite as threatening, but they still have this sort of attachment to being scary or disgusting. Why might that be?
Adrienne - I think we have an evolutionary repulsion for things that we find disgusting or repellent because they could in fact be dangerous to our health. There are scientists who actually study the emotion of disgust and find that it is universal to certain organisms or situations that could in fact be unhealthy or dangerous.
Will - This is an interesting one because we talk a lot about the past and now it makes sense as to why they steered clear of certain individual organisms, but this fear has stayed with us even as we enter a time where we understand far more about the natural world and what goes on in the dark in the woods. Why do you think this fear inducing image endures even as society becomes less afraid of the dark?
Adrienne - People today are fascinated and morbidly interested in the same things, both real and imaginary, that terrified people of antiquity. Telling tales and stories of fearsome dreadful monsters is thrilling. It's an adrenaline rush and people think it's fun to share scary experiences and fears of eerie creatures and monsters with their friends. So it's something that we do in groups and I think, as I mentioned, there's an evolutionary benefit to it. We need to be able to feel terror and react to it. And I think we humans still need to face fear in order to maintain not only our physical survival instincts, but also our psychological resilience. We humans seem to know and understand that feeling fear is important for escaping life and death situations, and I think Halloween is one of those outlets for expressing the primaeval fear and keeping all systems go.
Will - So to lose this fear would almost be to lose our humanity.
Adrienne - I think you could say that, yes.
06:44 - Why fungi are your new best friends
Why fungi are your new best friends
So where to start in our Halloween redemption arc? Well, you can’t have a proper witches brew without a few toadstools. Fungi have been long heralded as a sign of death and decay in the natural world. And, whilst that is true, it plays into the absolutely essential processes that this incredibly diverse group of organisms perform. To learn more, Will Tingle and James Tytko went into London to meet their field guide...
Emily - Hi, I'm Emily and we're going on a walk through Streatham Common Woods. I'm a wildlife educator and I like to help connect people with their green spaces.
Will - First and foremost, James, I'm going to serve you up this potentially mean question off the cuff. Do you think a fungus is a plant or an animal?
James - Now Will, what do you take me for? I know it's neither. I did a little bit of reading before we came out. I'm not going to claim to be an expert, but I'm pretty sure that was a trick question.
Emily - So actually fungi are their own kingdom. They used to be classified as plants and only actually got their own kingdom in around the 1950s. So way back when we used to classify things as either animals and anything that wasn't an animal was classified as a plant. Whereas now we know that they're their own kingdom and actually fungi are more closely related to humans than they are to plants.
James - I dunno about you, but I've come here today with a kind of preconception that fungi are in some way dangerous or I feel like I've been warded away from them by my parents, by other adults as I was growing up. Is that a justified reaction? Should we be careful around them or is that phobia by definition irrational?
Emily - I think a lot of people are scared of fungi because they don't really know what fungi do. I definitely walk around a lot hearing parents screaming at their kids not to touch mushrooms. Funnily enough though, you can touch all the mushrooms that you find. Even the poisonous ones are only really harmful if you ingest them. Whereas touching them is absolutely fine. Nothing's going to happen to you.
Will - I don’t know about you, but I think we should go and find some.
James - I'm very excited. Let's get going.
Will - That looks gross.
James - <laugh>. We're here to extol the virtues. <laugh>. That's what I envisage when I think of a mushroom, that brown toadstooly type. What am I looking at here?
Emily - So this fungus is called oak loving collybia. I quite like it because it jiggles and I really recommend if you're getting into fungi, to use all your senses. A lot of people smell fungi as well. Different fungi have really distinct odours. Some are just generally mushroomy.
James - Yeah, <laugh>
Will - Smells like soil. Why is that?
James - Are these ones edible?
Emily - No, I'm not a foraging expert. So I know a bit about the edibility of mushrooms, but in general I tend to not go down that route. Just because I find it a bit easier and I'm more interested in their roles in ecosystems
Will - As something very near and dear to my heart. You do mention the ecosystem and fungi play no small part in keeping that ecosystem up and running.
Emily - It's true. They do many things. I think primarily just decaying organic matter like leaf litter. They also break down parts of trees. So you have things like lignin, which is quite hard to break down, and they're the only things that are able to do that. So without fungi, we would just have wood everywhere. And breaking down wood is such an important thing, not just on dead trees, but living trees as well. So as trees get older, it's really important for the fungi to come in and basically rot out the centre of the wood. And as they decay wood, it sort of becomes an ecosystem engineer in that it will create hollows for owls to move in. Woodpeckers can then have it. Beetles start moving in. And you find that the tree, because of the fungi, becomes a hub of life in itself.
Will - We've gone this whole time without talking about the fact that it is the spooky season in Halloween and you've found some absolute corkers for us to talk about at such a topical time of the year.
Emily - So what we have here is dead man's fingers, Xylaria polymorpha. It's a really interesting fungus. I think it's called dead man's fingers because it's meant to look like a dead man's fingers coming out of his grave. A bit like in the Thriller music video. But actually dead man's fingers has a lot of medicinal uses. So in ancient Ayurvedic medicines, it encourages women to lactate.
James - Spoooooky.
Will - <laugh>
Emily - Super spooky <laugh>. And we've got some crystal brain on the other side of this log.
Will - I'm going to touch it.
Emily - Will does not like that.
Will - That is foul. That poor thing. It's just trying to do its job and we've come along, poked it and gone 'I hate that.'.
James - It looks like snot.
Will - We've just gone on about how, actually not all that much about mushrooms is toxic. However, what is this?
Emily - This is a cinnamon bracket. It is apparently the only known toxic polypore in Europe. It is a neurotoxin, so it contains about 40% polyprotic acid, which will cause irreversible damage to your nervous system, which is fantastic. And apparently if you ingest it, your pee turns purple.
Will - You can't just say that and not expect one of us to eat it. <laugh> James, you found an eyeball.
New Speaker - It's like a nipple <laugh>. I'm not afraid to say it.
Emily - These are collared earth stars. So I haven't picked them from the ground. They start off as balls and as it rains they basically unfurl open into this saucer shape and they push themselves off the ground. And what happens is when it rains, they'll release their spores from their spore sac. So it'll be like that. <Squeezes fungus and spores come out>
Will - Whoa.
James - It's like, if you can imagine pressing an old fashioned perfume bottle, it comes with that little...
Will - I feel like I've inhaled a lot of spores.
Emily - Actually, fungal spores are the highest organic matter that we inhale on a daily basis. Some fungal spores cause harm, but you've got to sort of be right with your nose in it while you puff it for it to go in. Some of them will cause lung disease, but actually fungal spores are so important and they actually help our clouds form, which then lead to rain. So when the water vapour is in the air, it needs something to condense against, to basically form clouds, which then cause it to rain, which is why there's so much rain and tropical ecosystems because the mushrooms and the clouds are forming this constant feedback loop.
Will - You've talked us through how great fungi are for the ecosystem, but far more important than that, I need them to be important to me. So apart from fungi as a food stuff, which they are increasingly more nowadays, what kind of benefits do we have that are gained from fungus that we perhaps don't even realise?
Emily - I think what a lot of people think of food fungi, they think of like fungi that you've literally directly cooked into meals. But fungi is incorporated into our day-to-day lives all the time. So yeast for rising bread, for example, fermenting of your beer, your classic penicillin, which has completely revolutionised human medicine. That is thanks to a fungus and a Petri dish. A lot of people report that it has completely changed the face of treatment, of mental illnesses. 6% of your medicinal fungi have some sort of like property in terms of anticarcinogenic properties. All great for the immune system. This is knowledge that's been around in a lot of traditional cultures for hundreds and hundreds of years that I think we really need to reconnect with our indigenous communities and bridge that barrier between the way we live and what they know of plants and fungi in general.
Will - Mm-Hmm. <affirmative> from the past to the future as well. Because fungi are apparently playing an astonishing role in not only the cleanup of toxic waste, but also plastic pollution as well.
Emily - Yeah. So mycoremediation or mycorestoration, as we know it, there's been lots of fungi that are able to break down toxins that we put into our environment such as pesticides, harmful chemicals. But as we know, there's so many fungi, millions of species yet to be discovered. So there could be loads of them that are able to do that. And it really emphasises how we should invest in mycology because a lot of the solutions to the problems we've created could very well be in that realm of science.
Will - The climate is warming. What can we expect in the future, do you think, to happen to worldwide fungal populations? And if it's bad news, is there any way we can help protect them?
Emily - Well, as we've discussed, fungi are so closely interlinked with the recycling of nutrients back into the ground, breaking down vegetation. And a big part of that is capturing carbon in soils through their affiliation with the trees. The plants aren't doing this alone. When we think of healthy ecosystems and forests that are able to be carbon sinks, that is due to the relationship that they have with the fungi. And so as a result, fungi is a really good indicator of soil health, which is so important for us in agriculture. Carbon sequestration, protecting fungi is pretty much hand in hand with fighting the climate crisis. So the biggest threat that fungi face is habitat loss, as with many of our species. So a major thing that we can do to help is sort of combat this need for tidiness that we tend to have as humans. Leaving more dead wood in place, incorporating dead deadwood into forestry management plans. Habitat loss isn't just a loss of woodland as well. Habitat loss is the degradation of our soils through agriculture. And we know that the more diverse soils are, the more we can sort of benefit out from agriculture in general as we move away from monocultures more into permacultures and also it holds the soil together so it prevents erosion, will reduce flooding, which is something that we're going to see more of as the climate crisis continues and we see more and more extreme weather events. So they're definitely really important to think about.
17:03 - Earthworms increase global grain yield by 128 million tonnes
Earthworms increase global grain yield by 128 million tonnes
Steven Fonte, Colorado State University
There is so much going on underground that is beneficial to us without us even realising. And one of the groups of animals that encapsulates this the most are the earthworms. Day and night, they labour underneath our feet to make the soil rich for agricultural use. And what thanks do they get? Kids throw them at each other and scream. Now that simply isn’t fair, particularly when you understand just how much earthworms contribute to keeping us fed. Steven Fonte is from Colorado State University...
Steven - Earthworms are really important in terms of recycling the organic matter. The dead plants that fall to the soil contain a lot of nutrients locked up that plants need and earthworms are key for helping to liberate those nutrients and make them available for new plants. They're also changing the soil structure a lot in porosity through their burrows and they make little aggregates or casts as they go through and chew up soil. And that really helps water infiltrate when we have a big rainstorm and also helps avoid erosion.
Will - I did see one estimate that there might be as many as 400 billion, billion individual worms in the top six inches of the Earth’s soil. I don't think they were talking about earthworms specifically, obviously, and there are a lot of other worm groups out there. But even still, if earthworms make up a fraction of that amount, it surely translates to a huge amount of food production that they're involved in.
Steven - So we looked at both two groups of crops. We looked at grains like corn, wheat, rice, and barley. And we found that earthworms contribute just under 7% of the total crop production or total production of grains worldwide. And that adds up to quite a bit. So it's about 128 million metric tonnes according to our estimates. And just to put that in perspective, that 128 million metric tonnes of grain, I was looking up the other day, puts earthworms right on par with Russia and Brazil in terms of global grain producers. So it's fourth and fifth place now at a national scale.
Will - Are these percentages or these amounts constant throughout the world? Is there one unified worm yield or are there places in conditions in which worms contribute more to food production?
Steven - Yeah, so the way our study did this is we looked at the distribution of crops globally and as well as management factors like how much nitrogen is applied and the soil type. And some soil types allow earthworms to have a greater benefit or not. And then we also looked at estimated earthworm populations. And so places where they don't fertilise as much, that's one factor that's allowing earthworms to have potentially a bigger role there. Also, the soil types that we find in a lot of developing places like in Sub-Saharan Africa and in Latin America and the Caribbean are more conducive to that earthworm benefit. And so we're seeing that earthworms are while the global average for grain contribution is about 6.5 or 7%. in Africa, that average bumps up to about 10% and 8% in the Latin American and the Caribbean region. And so it's not completely uniform, at least in terms of the relative increase. At the same time, if we're to look at the absolute increase, production levels are considerably higher, for example, in a lot of Europe and in a lot of Eastern Asia. And those are also places where we've estimated there to be a lot of earthworms. More so than, for example, we see a lot of the great plains in the US. And so in those areas, while the percent increase attributed to earthworms still hovers around seven or 8%, the absolute amount that they're contributing is considerably more. So earthworms are maybe increasing global grain production by 40 million metric tons both in Europe and Eastern and Southeast Asia.
Will - I mean, that brings up an interesting point from a complete layman's perspective here because obviously we are looking at trying to sort of move away from fertilisers, which we know are causing havoc with a runoff and problems in rivers and ecosystems. And we're looking for sort of more renewable 'green alternatives.' It's not as simple, surely, as throwing some more worms into the soil.
Steven - Yeah, and to be clear, we are not advocating that we go and inoculate soils with earthworms. That could be a bit of a contentious issue because a lot of earthworms are considered invasive species in parts of the world, in many parts of the world and can do a lot of damage to natural ecosystems adjacent to our farmlands. Within farms. They're generally positive, but there's management that we can do. If we have the right management practices, you know, like reduced tillage and actually supplying food for earthworms in the form of adding manure or compost or leaving crop residues behind, those practices can really help stimulate earthworm populations and they are there and their populations will increase on their own. We don't have to be adding them.
Will - So if we look after our earthworms, the earthworms look after the soil and hopefully everyone wins.
Steven - Yeah. They all work together so they benefit from any of the same things and hopefully we're able to leverage earthworms and other soil organisms to increase the overall sustainability and resilience of our agricultural systems.
22:10 - Why bats deserve better
Why bats deserve better
Iain Webb, The Wildlife Trust for Bedfordshire, Cambridgeshire & Northamptonshire
Finally, the animal that is maybe the most synonymous with Halloween, and one that has had a tough few years, shall we say. I’m sure most of you have twigged what it is by now, but we are of course talking about bats. To talk all about things with wings is the Wildlife Trust’s Iain Webb.
Will - Iain, thank you very much for joining me. I'm sure you are much the same as I am, but I love bats. Even if they had no use to us whatsoever, they'd still be a marvel of powered flight and echolocation. That being said, even discounting Halloween, do you think it's fair to say they've had something of an image problem particularly recently?
Iain - I think that's very fair to say, William. Very fair indeed. Unfortunately, yeah. Recent situations have meant that a bit of a misunderstanding and misplaced blame has been put at the toes or the wing tips of bats recently.
Will - It's almost unfortunate, isn't it, that because they have such a good immune system, they're immune to Ebola and COVID and stuff like that, that they act as such perfect reservoirs for passing illnesses over to us.
Iain - They can be, yeah. And when we get more engaged with our habitat and sort of interact with them more, then those risks increase. But not to say that every new virus that comes out is related to bats. It's just one thing that people tend to leap to because they're sort of synonymous with evil and nasty halloweeny things. So if you can pick on somebody, why not pick on bats
Will - Yes, and that isn't fair at all. In fact, they have immense uses, as callous as it sounds, immense uses to humans, not just to the ecosystem. Insect control. They're fantastically useful at that.
Iain - They are the primary predator of nocturnal insects throughout the globe. Really, it's quite phenomenal. There are 1400 species of bat throughout the world, and the majority of them, about 70% of them, feed on insects of different sorts. So in various places, they do have a major impact. You know, if you're talking about agricultural pests in certain areas where there's large numbers of bats, they have a massive impact, reducing the need for pesticide use on various crops. So much so that bats are actively encouraged by putting up bat houses to attract these numbers of bats to help save farmers money and reduce artificial chemicals being consumed by people and going into the wider environment. And we don't notice it, obviously because it's at night <laugh>, it's a phenomenal thing. And just relatively recently, they understand the value of having these bats is key.
Will - And ironically enough, given the bad flak they've had from COVID and Ebola and the like. In areas where you do see a bat population falling due to flooding destroying a bridge that they're nesting in or something like that, you see a rise in insect population. You see a rise in insect related illnesses.
Iain - Yeah, that's correct. Because bats are the primary predator of nocturnal insects like mosquitoes for example, if you remove that predator or reduce the numbers enormously, obviously those pest species will increase. With the climate breakdown going on and temperatures rising, then mosquito-borne diseases are spreading further north and will impact greater and greater populations in Europe and North America and North Asia. So not having bats there to reduce that impact is really serious.
Will - That obviously benefits us in our food production and our lack of getting ill. But no doubt it impacts the ecosystem as well
Iain - Definitely. Imperative, really. It's almost like bats are a keystone species being long-lived mammals that can cover quite a large part of the landscape. That loss for insect control is major, but it's also the other aspect of why bats are so important to ecosystems throughout the globe. You know, pollination and seed dispersal.
Will - You talk about food pollination, food production. Some of people's favourite foods, <laugh>, this is strong pandering now, but they are pollinated, created by bats.
Iain - That's correct, yeah. All those people who like tequila, I can imagine some nodding going on at the moment as we listen. The agave that they used to make tequila and mezcal is pollinated by the lesser long nosed bat.
Will - And chocolate as well. Chocolate and tequila. If you love chocolate and or tequila, you cannot hate bats. Despite all their uses, though, the majority of bats, if not all species of bat, are currently under threat and it's very easy to say because of climate change. But what are the main problems that bats are facing?
Iain - Well, other than climate change, <laugh>, habitat destruction, habitat fragmentation, direct persecution in some cases intensification of agriculture. Local persecution, the consumption of bats as well. You know, a good source of protein. A kilo and a half of fruit bat is really quite valuable to eat for people. Direct persecution not so much these days is there's more understanding and people understand the value of bats and their essential contribution to diverse ecosystems, but also the production of food, et cetera.
Will - With all that being said, with the importance on so many levels of bats and the vulnerabilities they face, what can be done globally. And for you personally, what are the Wildlife Trusts doing to help preserve bats?
Iain - Well, I think one of the key things is spreading the information. Letting people and the public know that bats are really valuable and shouldn't be thought of as vermin or disgusting, and really are essential for the future of so many ecosystems throughout the globe. Another one is the understanding on a sort of political level. The more people that support organisations such as the Wildlife Trusts or any other conservation organisation around the globe, there will be some interest in preserving bats and the more people that can support those charities, the greater the chance that bats can survive. There are various bats specific charities that could be supported and if you're fortunate enough to own a better piece of land or a garden or whatever, doing things in your garden can help bats as well. Increasing the number of insects in your garden will help bats to feed. Put a water feature in a pond, it doesn't have to be very big. Leave a bit of your grass long and probably actually eat organic vegetables and organic food as well. You know, the use of pesticide has caused the crash in so many species of insect that has an impact on bats. The other thing that could be done is go out and enjoy bats and do things with bats. There are many bat walks and bat tours that go on. The Cambridge Wildlife Trusts do a bat punt safari. So if you happen to be in Cambridge between May and September, come along on a Friday and Saturday night and come on the river and you'll be surrounded by bats.