Will we ever ‘cure’ Mental Illness?


Jonathan Cooke

People do not wake up one day realising that they have a mental illness; that their view of the world is clouded by a poorly defined alteration of their brain chemistry. It can take days, months or even years before a person comes to terms with that what they are experiencing is not ‘normal’. Even at that time, they may not immediately seek medical advice, to some seeking such advice is an admission of weakness; an inability to deal with what everyone else is dealing with.

That is not to say that people cannot recover from mental illness. The flood in the pharmaceutical industry of different pills and tablets that are prescribed to people to help their conditions would lend credibility to the theory that these conditions can be coped with. However medication doesn’t work for some, and for others it can make the situation even worse than before. Pills are not a one-stop solution, they do not suddenly fix your brain chemistry overnight. Even SSRIs (selective serotonin uptake inhibitors) only help to limit the amount of serotonin your body absorbs, it doesn’t alter the amount your body produces.

The negative reactions to these tablets betrays a much more important point: the debate over the cause of mental illness is still hotly debated. There is undeniably a natural-genetic component to their disorder. However does this make the development of mental illness inevitable? Or does it merely increase the chance of mental illness arising in a person and its environment that provides the trigger?

In addition, there are other ‘cures’ that over the years have been used to try and treat ‘mental illness’ over the years. It was not that long ago that electro-convulsive therapy (ECT) was prescribed as the most efficient therapy when trying to treat anything that was considered a mental illness. Whilst its efficiency at treating some conditions has been noted in the literature, very few therapies have generated such a heated debate, perhaps due to how the treatment is perceived. After all, no-one is likely to warmly receive the idea of having an electric current shot through their brain.

The evolving definition of what and what isn’t a mental illness should give pause to the idea of a cure. It wasn’t until 1987 that homosexuality was removed from textbooks which listed psychiatric disorders and being transgender is soon to be removed as well, replaced with the more accurate but no less weighted term ‘gender dysphoria’. Societies needing a cure for conditions which it doesn’t understand is perhaps its greatest failing. If we don’t understand or accept something, it is that something which is regarded as being in the wrong and having to change rather than our attitude towards it. It is therefore the reaction that these marginalized minorities receive that is probably the root cause of their higher than average rates of depression and suicide, rather than who they are themselves.

What use is a cure if it does not cure the stigma that comes with a mental illness. A book by Nunally J (1981) looked at the semantics that people typically associate with people that have a mental illness. Respondents, when describing a mentally ill man, were most likely to use semantics like “dangerous, dirty, unpredictable and worthless”.

That may have been several decades ago and times have changed; there are more public advocates of mental health awareness and the advent of the internet has allowed people to find others experiencing similar symptoms, helping them to forge support networks. However, to those unaware of those advocates or support networks, what are they greeted with? Most shows on ‘mainstream’ media that try to portray mental illness inevitably demonize characters on TV shows with mental health illnesses as either violent or unlikeable.

Full disclosure, I have not watched either 13 Reasons Why or To the bone, arguably the two biggest attempts to portray characters with mental illnesses recently. However, both were widely criticized, by the depression and anorexic communities respectively, for their inadequate portrayal of the issues that they raised. It would be naïve to suggest that a people are not heavily influenced by what they watch on television. In a paper in 1978, it was shown that people who watch a lot of crime-related television and police dramas are more likely to vastly overestimate their chances of being a victim of crime, as well as overestimate how many police officers and judges there are. (Gerloner et al. 1978)

These criticisms are not based on wild speculation either; Granello & Pauley (2000) demonstrated that portrayals of mentally ill characters on TV and film are typically made out to be “violent and unpredictable”. This is not just negative for those who wish to identify with a character on TV that represents them, but also for the general public. With the ever emerging evidence that genetics play a part in the development of mental illness, such demonization of the mentally ill allow the rest of the public to separate the mentally ill into a ‘other’ group of people, different and unique to them.

This separation of the population into ‘normal’ and ‘other’ leads to a disassociation and an inability to understand that mental illness is a sliding scale of grey with no two conditions exactly alike. My depression and anxiety do affect me, but they affect others differently to me. There are similarities, but also differences. It is this nuance that is missing in our discourse when we discuss mental illness in the media and with the public.

Some people get better without a recognized ‘cure’. They open up, discuss their problems and find they are not quite as alone as they thought they were. There is power in the ability to talk with your fellows about how you are feeling. But how can they hope to ever feel they are better if society refuses to acknowledge that someone can recover from mental illness without the need for a specially crafted ‘happy pill’ that solves all their problems? Curing mental illness is a lofty and admirable goal; but my training is not in that area and so it would be unwarranted of me to posit that such a cure is achievable.

Cures begin by having an accurate picture of what we are trying to cure. We could not cure the plague by ‘bleeding’ the badness away. To help those with mental illness, we have to understand that many of the common mental illnesses, depression/anxiety, are exacerbated by the society in which we live. Therefore, should not the conversation be about curing society and not those that live within it?

Brain Altering Parasites


Jonathan Cooke

Fans of The Last of Us might be familiar with brain-altering parasites. These little critters and fungi are slowly creeping into the popular imagination thanks in part to media using them as the instigator of the ever-popular zombie apocalypse genre. The ‘bad guy’ of choice in The Last of Us is the parasite Cordyceps; a fungus that is represented by multiple species which ‘zombify’ their hosts, turning them into vessels for their reproduction.

Fortunately for you, Cordyceps; or more precisely Ophiocordyceps only prey on tiny insects found on the forest floor. In fact, they are quite an effective pest control, helping to keep insect populations in check.

Generally, whether or not the parasite kills their host, it will manipulate the host into a situation that is more advantageous for the parasite. For instance, if the current host is merely an intermediary for the parasite can reach their final host they will manipulate the current host’s behaviour to make it more likely they will come into contact with the final host.

Such parasites include the protozoan Toxoplasma gondii; which infect rodents, but reproduce in cats, alter the behaviour of their rodent hosts. Several behavioural experiments have found that rats infected by the parasite are much more likely to take risks than their non-infected counter-parts. This leaves them more susceptible to eaten by their feline predators, thereby continuing the parasites lifecycle.

These behavioural changes are usually brought about by manipulating the hosts brain chemistry, either increasing or decreasing the brains response to signals it is receiving. In the case of the rodents, T.gondii ‘makes’ encourages risk-taking behaviour by ignoring environmental stimuli that work to make them dive for cover, such as the scent of cats. In several experiments that exposed rats to the smell of various different organisms, rats infected with T.gondii tended to frequent areas that smelled of cats and were not scared of cats when they were in the area. This is part of the parasite’s ‘extended phenotype’; where the behaviour of the host changes to maximise the survival chances of the parasites genes.

Again and again these manipulations have been observed in the animal kingdom (although for the most part the actual mechanisms are not fully understood, I should know, I wrote my dissertation on it) but what if they do affect humans?

Are humans manipulated in the same way that others are, to benefit those organisms that are so much smaller than us?

Humans are parasitized by many different organisms, tapeworms being a well-known example. However, most parasites we know steal nutrients from the food we eat, or feed off us directly, like ticks. In both cases, they don’t kill us, and don’t need to do something as energy consuming as manipulating their host’s behaviour.

Manipulating your host’s behaviour typically indicates that you want your host to move somewhere or do something that would be out of the ordinary for them; but is advantageous for you as the parasite, e.g. in the case with Cordyceps, which want their spores to be better distributed, or you want your host to be eaten, such as with T.gondii.

Neither of those strategies would be viable in humans. We don’t tend to get eaten by other organisms until we die naturally and unless the parasite only breeds around beach resorts in Tenerife, there’s not much point in changing our behaviour.

So, what if it’s accidental? What if we get infected by something were not supposed to? How might a parasite, not realising its reached a reproductive dead-end, affect us? Well ever since humanity has been looking after our feline friends we’ve run the risk of accidental infection by T.gondii, although no one is quite clear as what this infection might do to us. Infection rates vary widely across the country and for the vast majority of the population infection is completely asymptomatic, though infection can also trigger toxoplasmosis which can have lethal consequences.

Some observational evidence from studies, seem to suggest that infection has a demonstrable effect on the behaviour of those who have picked up the parasite, although the consequences do differ between males and females. Women seemingly become more intelligent, affectionate, and more likely to follow rules, whilst men tend to mellow out, becoming more loyal and mild-tempered when compared against other males.

The only trait that those who are infected share across both genders is a higher level of neuroticism, being more likely to blame themselves for problems in their lives and to have a high sense of insecurity.

However, these correlations are just that – correlations. No work has been done to prove that T.gondii is what is causing these behavioural changes in people – if they are changes at all.

Perhaps the reverse is happening; those of us with these traits are more prone to getting infected. Very little work – for obvious ethical reasons – has been done to see T.gondii interacts with the human body. However, perhaps we can take small pleasure in the idea that it is going to be convincing us to get eaten by lions anytime soon.

Behaviour altering parasites is a new, emerging field in biology; its effects are rarely documented and even more rarely understood in how they work. For many years, however, there has been a fundamental view that humans are not affected by such parasites and that we are apart from the animal kingdom in this regard.

Perhaps it’s time we address this view?

Are Aliens Out to Get Us?

Jonathan Cooke

For a species that is so often looking up to the stars thinking ‘are we alone?’, we tend to populate our fictional universes with less than benevolent compatriot species. Look at some of the more popular science fiction movies and stories to be released in the last century. War of the Worlds, Alien and even the recently released Life all approach the question of extraterrestrial life the same way: it’s out there, and it’s out to get us.

Since it is such a speculative field, there is virtually no consensus on how we might react upon first contact, simply because we don’t know what sort of aliens will turn up. The developing view is that, if there is other life in the universe it’s likely to be microbial in nature. If there is anything that the much-lauded tardigrades have taught us, it is that microbial life will find a way to survive. Therefore, most space-based programs are focused on the detection of this so called primitive life (Is it fair to call it primitive when they can do some pretty amazing things?).

Most missions have focussed on our closest sister, Mars, and its dry riverbeds that provide some tantalising bits of evidence that all might not be dead on the red planet. Methane is unusually high in the Martian atmosphere. As a gas that is highly reactive and therefore tends to disappear without regular top ups, this is indicative that something is replenishing it. Methane in our own atmosphere is typically produced from biotic sources; meaning that, from our experience, traces of methane might be indicative of life.

Of course, alternative theories exist for the presence of methane, including geological sources of the gas. But what if our rovers were to discover bacteria living on the surface of the red planet? What would we do with it? Well it wouldn’t be coming to our planet anytime soon –  none of the rovers currently on the planet are equipped for that sort of mission. Even then, the samples would have to be tested and tested again to ensure that they aren’t just contaminants from Earth. They’re unlikely to alive by the time they reach Earth under strict contamination procedures. So, don’t worry, no Martian plague will be giving you the sniffles.

Alien View From The Moon Earth

Image Credit: Max Pixel

Anywhere else we are currently scouting for life would face similar contamination issues. Europa for instance, one of Jupiter’s larger moons, is being targeted as our next life-seeking venture to the stars. With an ocean thought to be buried underneath its permanent ice-sheet casing, many scientists believe that ocean temperatures may just be warm enough to support the development of life, if again, simple in nature.

So that basically covers what’s known; in our solar system –  at least there won’t be any tripods bursting out the ground anytime soon to exterminate us and Tom Cruise! But what about farther afield? Well, many radio telescopes are turned to the farthest reaches of our galaxies; and news publishers love a good story of astronomers finding ‘habitable’ exoplanets. If you pay attention to the Drake equation, there should be 1,000 to 100,000 intelligent civilizations in our galaxy. So why haven’t we heard from our cosmic neighbours.

There are many reasons that we might not have heard from them, and many reasons we should be thankful for that. If we’ve learnt anything from our own behaviour on Earth, the less technologically advanced society rarely survives first contact with a more advanced society. The most glaring example of this is the fate of the Native Americans in the wake of Europeans discovering the New World.

This is the cautionary tale that Stephen Hawking told in 2010 when questioned about our first meeting with E.T. On the other hand, many scientists question the validity of Hawking’s reasoning. As mentioned above, many are more worried about what the aliens bring with them accidentally rather than deliberately. As illustrated in H. G. Wells’ famous novel The War of the Worlds, contact with a previously unencountered pathogen can be devastating to any organism. Whether it was the Mayans and typhoid and influenza, to African swine fever in the American pork industry, foreign pathogens tend to wipe out whole communities before any resistance can develop. Just ask the abandoned Mayan cities of the Amazon.

Of course, other questions arise which are a bit harder to answer. What if the alien civilization is warlike? What if their ethics system is not comparable to ours? What if, and this has been considered, we are the ‘life, but not as we know it’ variety in the universe? Many astrobiologists have postulated that silicon based lifeforms may exist (we are carbon based), so what if we’re just too alien for them to visit?

An even sadder alternative is that we are truly alone, that alien life is non-existent, (considered highly unlikely) or that we are one of the first intelligent civilizations to evolve in the galaxy. Perhaps intelligent life is the exception rather than the rule. The Fermi paradox points to how extremely unlikely our own path to survival was. Maybe many creatures on that road seemly get snuffed out by Natural Selection before that point.

In any case, what keeps many scientists up at night is not thoughts of alien invasions, but thoughts of alien illnesses. Perhaps what we should be preparing for, and indeed looking for, is what makes little green men feel ill.

The Science of Crowds

Jonathan Cooke

If you’re a Premier League Football team, you must follow a simple formula for winning the title. First, you win at home against other teams. Then, against lower league opposition you win at their ground as well.

The ability of a crowd to motivate players has long been established as a factor that rival managers consider when they visit a home ground. The fan base is often described as a ‘12th man’, spurring their team on to do incredible things. But do crowds really have that effect? And can crowds have more palpable effects on the world than simply winning football games?

crowd pixnio.jpg

Image Credit: Pixnio

The concept of ‘crowd wisdom’ can be traced all the way back to Aristotle, but the most quoted example comes from 1906 and Francis Galton, a famous statistician. He observed that the median and mean guesses of a crowd that were attempting to guess the weight of a cow came astonishingly close to the actual value –  within 1%.  

It doesn’t really matter whether your crowd is made up of Nobel Prize winners or the people from your local pub (who may or may not be prize winners). Imagine you are asking several people how many jellybeans are in a jar. You’ll get a few people overestimating and you’ll get a few people underestimating. Whilst you would imagine this would skew the results away from the actual number of jellybeans, it doesn’t really. In fact, you tend to get a similar number of each type (overestimates and underestimates) of poor guess, so they cancel each other out when it comes to working out your average.

To put it another way, as an individual you may never win a ‘guess how many of x is in this jar’, but get a big enough crowd together and you’ll get an average which is close to the actual answer.

It’s for this exact reason that the votes of Dixville Notch in New Hampshire U.S.A are broadcast ahead of the rest of the country. Prior to the 2016 election, this small village had successfully predicted the eventual winner of the presidential election eight out of fourteen times the results were broadcast, (to those interested, they didn’t predict Donald Trump, but then again who did?) and is generally seen as a predictor of how the rest of election will go.

Collectively pooling our intelligence has helped us in many numerous ways. Wikipedia is the greatest example of them all. An encyclopaedia that is generated, and edited, by an internet population of 3.2 billion people. Now of course, as your professor will tell you, never source directly from Wikipedia. Many pages, particularly small ones that are very specific and dull to the clear majority of the population, are trustworthy; they are maintained only by those who care about it.

Popular pages, on the other hand, such as those of celebrities or politicians, are regularly accessed and edited by individuals with agendas, or just those who want a laugh. In doing so, they can rapidly spread false information which quickly becomes group intelligence, which can have disastrous consequences.

“Crowd crushes” were for a long time seen as the main result of large crowds working towards a singular goal (indeed, for a long time, crowds have been seen as being more stupid than individuals). A crowd can act as a ‘wave’, which can ebb and flow and is a danger to itself. It’s been observed that if you put more than 7 people within a square meter, then when you apply force to them then they’ll act as more of a wave than individuals. This can result in people literally being crushed to death as the pressure of crowds forces the air out of their lungs, or industrial strength fencing being bent by the sheer weight being put on them.

Thankfully, modern studies of crowd behaviour focus on modelling natural patterns when groups of people walk in a similar direction. For instance, much like geese, it’s been observed that when a group of people, three or larger, walk in a similar direction then they’ll naturally form a V-shaped formation, which forces crowds to part around them and facilitates faster movement. This information is being used to better coordinate fire exits.

The key ingredient for crowd intelligence to work is that all decisions taken by the individuals must be independent of one another. To take the jellybean example, the best way to ensure you get a more accurate estimate is to hide participant’s answers from one another. Individuals when given more information tended to group towards a similar set of answers, which means you get a narrower range of answers, but the accuracy can get worse.

The stock market crash of 2008 was largely down to this problem. Many banks followed the example of a few, loaning out unsecure loans and mortgages, falsely believing that because others hadn’t failed, neither would they. This incorrect consensus amongst banks meant none saw the inevitable crash coming and so therefore were unable to respond to it.

‘The wisdom of the crowds’ is routinely used by politicians and those who do not wish to listen to experts on subjects. Whilst crowds can be smart, they are only useful for numerical decisions that have one simple answer. However, studying crowds and crowd behaviour will allow us to ensure the safety of every individual caught within the group-think.


Slaying Stress with Science

Jonathan Cooke

We’ve all done it. From first years going through their first bout of January exams, to third years who just want to get it over with, we’ve all left revision a bit late now and again. We’ve all looked outside the windows of the IC at 3am and wondered why we waited until the day before to start writing the essay that counts for 50% of the module. It’s natural to feel stressed in these situations, and there are lots of ways to alleviate that feeling. But, do any of these methods have any scientific proof?


Image Credit: Wikimedia

Have a Plan

It may seem simple, but making a plan for how you are going to tackle a deadline or exam can be very beneficial. A Harvard study published in 2011 that surveyed 3,000 adults found that the simplest and most effective way to combat stress was to plan out how you were going to tackle the problem and get the hardest part of the process out of the way first, allowing you to do the easier things later.

So, if you’re struggling with that essay, focus on writing it first, get a first draft sorted out weeks before the deadline. This affords you time to do the easier things, such as referencing and checking spelling/grammar at a much more leisurely pace. If you’re revising for an exam, get the harder stuff out of the way. Pick the topic that bores you the most and revise that first, that way, as you get closer to the exam you get to revise the stuff that interests you more.

Getting the hard things out of the way and crafting a to do list for what you want to get done in the week are really simply ways to space your workload out and keep stress levels down.

Take a Break

Spacing your work out not only gives you more time to work on it, it gives you more opportunities to procrastinate. Even the best of us are guilty of it, we go on YouTube and promise ourselves we’ll only watch one video, then suddenly it’s the next day and you’re watching a chimpanzee riding a segway (this, if anyone is interested, is my favourite procrastination link).

You might feel guilty for filling your time up so wastefully, but in reality procrastination is helpful way for your brain to alleviate stress. Many us enjoy watching videos that are completely separate from our degree area; cat videos, for instance, number up to 2 million on YouTube alone and have on average 12,000 views on each one, which is more than any other category of video!

Listening to music, watching your favourite YouTuber or just having a good laugh all have been shown to help release endorphins, which help combat the stress you might be feeling. Of course this must be done in moderation or you wouldn’t get any work done, but allowing yourself a break every so often from work allows you to de-stress and approach your work fresh.

Go Outside

A lot of recent work suggests that going outside for a walk not only helps to alleviate stress but can improve your overall well-being. A study published in the Landscape and Urban Planning journal found that people who live nearer greener pastures and open fields tend to feel less stress than those that don’t. Why? Getting out into the fresh air and sunlight helps them to relax and feel more at ease with their surroundings.

Additionally, living near such greenery necessitated a moderate amount of light exercise. Exercise has long been shown to help people keep a positive mood than those who don’t exercise, as recognized by the World Health Organization in 2011.

Now, this by no means you have to start hitting the gym; it isn’t for everyone. But if you’re feeling a little burnt out from work, get outside for a bit: go for a 15 minute walk (take a coat if it’s raining) and give yourself time to relax.

Whilst we hope the methods mentioned here are useful in the goal of combatting stress, for some of our readers they might not. If that is the case, and you feel that you are struggling to cope, we here at PH7 would like to point you to a few resources that are available to help you focus:

The University of Sheffield offers a wide array of techniques which can found on their webpage here: https://www.sheffield.ac.uk/ssid/well-connected/academic-pressures/stressed/managing-exam-anxiety

Additionally, the University Counselling Service offers 30 minute triage appointments, which allow you to discuss your stress with a trained counsellor and work out what is best for you: http://www.sheffield.ac.uk/ssid/counselling

Nightline is also a fantastic resource that has trained volunteers that are available to listen to you, no matter how large or small the problem from 8pm to 8am every night. Tel: 0114 222 8787

Bringing Lost Coral Back to Life

Jonathan Cooke

If you weren’t aware of just how badly coral reefs have been faring due to global warming, it was announced in late November that just over two-thirds of the Great Barrier Reef has been killed off due to warming seas. That is over 435 miles of coral that has died, three times the distance between Sheffield and London. Coral reefs account for the largest areas of biodiversity in the ocean and are considered some of the most diverse habitats on the globe.


Image Credit: Wikimedia

Losing these areas of biodiversity is a disaster for many marine species. Coral reefs act as both a nursery and a shelter for smaller fish, helping to shield them from the ocean’s larger predators. Indeed, many species are specialized to living on or around reefs, creatures such as everyone’s favourite clownfish, Nemo. Without their symbiotic partners, the anemones, these clownfish face likely extinction.

The main problem facing coral reefs is that the rate at which they are dying is massively outpacing the rate at which they grow. The gradual heating up of our oceans is intolerable to many species and causes them to instinctively eject the algae, or zooxanthellae, with which they have formed symbiotic relationships. These algae are responsible for the brilliant and vivid colours we are so familiar with, and provide the coral with nutrients, via photosynthesis, which are key to their survival.

‘Coral bleaching’ is the direct result of the ejection of these algae and whilst it does not spell the immediate death of the coral itself, it leaves them considerably more stressed and prone to suffer from disease. As such, mass coral bleaching is seen as a warning sign of coral’s imminent death.

Can anything be done to counteract such effects however? Well that really depends on which reef we are talking about. Most coral species are ‘endemic’, typically found within one particular reef system. You are unlikely to find many shared species between the Great Barrier Reef and the Florida Keys reef, for example. This means our approach to fixing the reefs must be adapted in each instance to better tackle the issues each coral species faces.

However, some techniques can be transplanted. Ruth Gates, a biologist over in Hawaii institute of Marine Biology, has become somewhat of a coral gardener, growing and cultivating baby corals in controlled environments away from the sea. Since polyps (organisms that build the reefs) grow at tediously slow rate, growing mere millimetres over the course of years, we must find another, quicker way to replace the destroyed coral. It turns out that breaking the polyps up increases the rate at which they grow, as they work quickly to replace the damage.

This finding has fuelled our ability to seed the water with millions upon millions of ‘microfragments’, which can be planted on the surface of dead or dying coral and use this as a structure from which to grow. This technique works for other types of reefs as well; in Britain, many have been using the shells of farmed oysters as bases for young oysters to grow from.  Having a rooted skeleton saves the new coral the energy it would expend rooting itself to the ground, which it can then invest in growth.

Planting juvenile corals is not the only method of reseeding an area and it does have its difficulties. Growing coral takes a long time as previously mentioned; you could be waiting almost half a decade before the corals are ready to be seeded. Even then there’s no guarantee they will survive. Instead, some scientists have taken to using larvae to try and reseed corals.

Coral larvae is free-floating in nature due to their method of reproduction. Adult corals simply release either eggs or sperm into the sea at one or two points throughout the year in mass spawning events. Most coral species do this at the same time, which could lead to some confusing parentage! The eggs are then fertilized in the water column and the larvae develop there until they are big enough to anchor themselves to the seabed. Now, for a sedentary animal this makes sense; releasing your children to be carried by the current limits the chances they will settle down next to you and compete for resources.

However, this method would be ineffective for reseeding efforts as you never know how many would actually settle. To combat this, the teams trapped the coral larvae underneath mesh enclosures so that they would stay at the sites that needed to be rebuilt. Whilst many of the coral settlers will die, enough will survive to sexual maturity to begin the next lifecycle of the reef; in the world of coral breeding, it’s a numbers game.

Now, these methods are all well and good but they miss one key problem: all these corals will be brother and sister. They’ll share all the same strengths, but also all the same weaknesses. As such, any environmental triggers that induce bleaching will cause them all to bleach, landing us back where we started. However, by collecting larvae from nearby surviving reefs, as well as breeding different genetic varieties of coral, we can make sure that we build a genetically diverse reef that can survive into the future.  

Rebuilding the reefs we have destroyed will by no means be an easy task, but it is one we must accomplish. The Great Barrier Reef existed for almost half a million years before we arrived; it is our duty to ensure it is there after we are gone.

The Real Horrors of the Animal Kingdom

Jonathan Cooke

If don’t like Halloween much, with the plethora of ghouls and zombies prowling the streets in search of sweets, be thankful you don’t live in the undergrowth. Many of the creepy tales and monsters we create are nothing compared to the nightmarish ways some organisms live their lives. This Halloween, let’s take a look at the creepy world of the animal kingdom.


Image Credit: David P. Hughes, Maj-Britt Pontoppidan/Wikimedia Commons

Whilst they may not be crawling out of graves to feast on the brains of the living, some organisms have found a way to use the dead bodies of others for their own ends. Some, such as the fungus, Ophiocordyceps Unilateralis (or cordyceps, for short), hijack living organisms too. Cordyceps infects and controls living ants, forcing them to climb into the canopy and clamp down on the underside of a leaf. There, the fungus sprouts its fruiting body from the back of the ants head; ready to release its spores down onto even more unsuspecting ants.

Other parasites use their host’s bodies against them, increasing their own chance of getting eaten. Take the case of Toxoplasma gondii, a parasite that infects rats, but can only successfully reproduce in cats. Now, the obvious problem is how to get the rat into the cat; rats having a highly evolved sense of predators, deliberately avoiding areas that are heavily populated with cats. T.gondii gets around this by effectively disabling the rats’ fear of cat scent, making them more adventurous and likely to get themselves eaten.

In what is quite a macabre display, the bone house wasp has an interesting taste in interior design. Like many of its parasitoid wasp brethren, this wasp gives its young a tasty snack to munch on as they develop from larvae. The only caveat is that their prey is still typically alive whilst they are being eaten. If you are unlucky enough to be the chosen baby-snack, the wasp will typically inject you with a heavy dose of neurotoxin to paralyse, but not kill, you. They will then drag you back to their nest and lay several eggs inside you, which will then hatch and consume you from the inside out.

Not exactly a glamorous fate, but this is where the bone house wasp takes it to a bit of an extreme. See, the mother isn’t exactly attentive, rather leaving her young to their own devices once she’s finished laying. This does raise the risk of her young getting eaten, and she didn’t go through the hassle of dragging a tarantula home for that to happen. Instead, mother wasp goes and rounds up a bunch of ants and meshes their corpses together to line the entrance of the nest. As she typically selects the soldier ants of aggressive species to be part of her avant garde wallpaper, its speculated the pheromones given off by the ants dissuades potential predators from looking in the nest for a snack.

Vampires are usually a low-key costume for those of us who haven’t had time to build a fully functioning Iron Man suit, but some organisms have become highly specialised blood drinkers. The main problem with blood drinking (also known as Hematophagy) is the high levels of iron found within it. In such quantities, blood is actually highly toxic, unless you have the mechanisms to cope with it. In vampire bats, for example, a specialised tract has evolved in the digestive system to filter out any excess iron.

Unlike Dracula however, these bats typically feast on large, bovine species and tend not to kill their food source, only drinking what they need to survive. Human bloodsuckers are more miniature, and are a lot more deadly. Mosquitoes are the bane of many peoples summer holidays, and for good reason. Whilst the males of the most species exclusively feed on pollen; the females are blood-suckers, and can’t even lay eggs unless they have sufficiently gorged themselves.

The problem with mosquitoes is that they are excellent vectors for all sorts of horrible diseases. Malaria, dengue fever, HIV: all of these are transmitted by mosquitoes, delivered straight into our bloodstreams due to their dietary habits.

Much like the grim reaper, some animals have entered our folklore as harbingers of death. The aptly named deathwatch beetle acquired its name thanks to its feeding habits as a larva. In the past, people would tend to die at home, with loved ones watching over them. In this silence, many would hear a tapping noise coming from the walls and suspect the dead were coming to collect their family member. In reality, this tapping noise was caused by the larvae of the deathwatch beetles, chewing through the wooden walls, which doesn’t exactly sound reassuring.

On the 31st October, we humans like to embrace our spooky side, going out of our way to scare ourselves with stories of monsters and ghosts. However, this Halloween consider this: the natural world is much darker, and much scarier, than anything we could dream up.


Happy Halloween.