A Bad Case of the Zombies: Could a virus really cause World War Z?

A zombie playing the sousaphone. I wanted one playing the trombone because of the tenuous trombone/bone/zombie connection. Ho hum.

The other day I went to see the film, World War Z. It was fine and thus ends my review of my enjoyment of it. Anyway, the real World War Z will of course be between those who pronounce it “zed” and those who pronounce it “zee”. World War Z is based on the 2006 novel by Max Brooks (a follow-up to his 2003 book, The Zombie Survival Guide). Both books are excellent and if you’re not too bored of zombie-based fiction then you should read them. I say this because there seems to have been a recent upsurge on things about zombies of some kind. The zombies are everywhere, which I suppose is ironic. The film stars Bradley Pitt as a retired United Nations employee who must travel the world to find a way to stop a zombie-like pandemic.

In the film being a zombie (Zombieism? Esprit de corpse? Zombosis?) appears to be caused by a viral infection, primarily caught by being bitten by a zombie. Those who are bitten appear to die within about 30 seconds and then reanimate with slightly cloudy eyes. They then become very aggressive and begin to chase down victims to bite them and spread the infection. They do not appear to eat their victims; rather keep on going just generally being runny and a bit bitey. I say runny as in they run a lot rather than hinting at any advanced state of decomposition. Although eventually the zombies do appear to go a bit rotten.

I accept that all this doesn’t have to be dead-on realistic (ahem) but there are a few problems with the concept. It’s assumed that the mass zombification is caused by a viral pandemic. Yet time from being bitten to turning into a zombie appears to be too rapid for this to be the case. It would take a bit longer for whatever virus it is to circulate, invade cells, hijack their genetic machinery and start producing copies of the virus and manifest symptoms. Especially given that the virus appears to completely take over the host’s central nervous system and musculature while leaving the rest of them deceased. Like a more infectious version of Britain’s Got Talent.

While viruses certainly can be deadly they generally need the thing they’re in to be alive to make more virus and spread them. This might be by sneezing in their co-worker’s face, not washing their hands, licking fruit bowls etc. The zombie virus doesn’t appear to need this. It kills the host and still somehow has them running around. Where is the host’s energy coming from? Could the humans all just hide and wait for the zombies to fall apart? Granted this would make the film quite dull. Nobody wants to watch a film where people eat sandwiches in a bunker waiting for their enemy to decompose. Although Panic Room is OK.

The idea however that an infection can control its host’s behaviour to help its spread is well established in nature. For example, malaria is an infectious disease spread by mosquitoes, caused by one of five species of the Apicomplexan parasite, Plasmodium. Most deaths from malaria are caused by Plasmodium falciparum. It really is an awful disease with the WHO estimating that in 2010 there were 219 million cases of malaria resulting in 660,000 deaths. As I’ve hinted, Plasmodium can change the behaviour of mosquitoes to spread itself faster and wider.

The common Plasmodium Puppet. Also known as the mosquito.

Once in a mosquito, Plasmodium needs time to move to the mosquito’s gut to mate and reproduce to form ookinetes. These are a sort of mobile egg. The story of Plasmodium really ruins Humpty Dumpty. Ookinetes develop into sporozoites (Literally: “animal seed”. Don’t go planting your hamsters though!) and travel to the mosquito’s salivary gland. Prior to this it doesn’t do the Plasmodium much good for the mosquito to bite someone with the risk the mosquito might get killed during the attempt. So Plasmodium tries to alter the mosquito’s behaviour to prevent this. For a mosquito to get your blood it has to drive its proboscis through your skin and find a blood vessel. The longer this takes the greater its chances of being noticed and squashed. Like if McDonalds killed you if you queued too long rather than years later of heart disease. If a mosquito finds it too difficult to draw blood they’ll quickly give up.  A mosquito with ookinetes in it will abandon biting quicker than an uninfected one.

However once the sporozoites reach the mosquito’s mouth, it benefits Plasmodium for the mosquito to bite as much as possible.  The Plasmodium at this stage appears to make the mosquito “hungrier”, causing it to drink more blood and visit more hosts to get it. In these ways and more Plasmodium is manipulating its hosts behaviour to reproduce itself and spread more easily.

Some species of tapeworm live in the three-spined stickleback but also spend part of their lifecycle in the birds that eat these fish. The tapeworms can alter the behaviour of the fish making it more likely they’re caught and eaten. As you’d expect, sticklebacks try to keep away from heron. They stay away from the surface and if a heron appears they dart away. Sticklebacks infected with tapeworm appear to become more fearless, staying near the surface to feed even if a heron is about. These are more likely to be eaten and the tapeworm gets where it wants to go; into the heron.

Similarly, Toxoplasma gondii, a protozoan of “don’t go near the litter tray if you’re pregnant” fame, needs to move between rats and cats and back again to complete its lifecycle.  A healthy, uninfected rat will normally become anxious when it smells cat urine staying away from where they smelled it.  They will literally piss off. Rats infected with Toxoplasma however do not become anxious when they catch the scent of a cat, do not avoid it and increase their chances of becoming dinner.

Toxoplasma also appears to alter the psychology of humans it infects. Men infected with Toxoplasma become less willing to follow rules and less worried about being punished for breaking these rules. Women infected with Toxoplasma become more outgoing. Toxoplasma: the party protozoa! I probably shouldn’t get into marketing. It is not fully known how this occurs although there is some evidence that Toxoplasma increases production of the neurotransmitter dopamine and in males, increases testosterone levels.  It should be noted that this evidence is largely from rats. A lot of evidence is.

Afraid? Are you a man or a mouse? Or are you infected with Toxoplasma?

All of our examples have been parasites, but the infection is World War Z is cited as a virus, which I guess technically can be seen as a parasite. Can a virus alter its host’s behaviour to aid its spread? You bet your hot butter on toast it can! The baculovirus, infects the caterpillars of the European gypsy moth and causes them to climb to the tree-tops. Once there they die and liquefy, releasing thousands of viral particles to rain down and infect more unfortunate caterpillars. In this way Lymantria dispar forces the caterpillar to turn itself into a piñata and explode itself, raining down sweets i.e. a nasty virus, on other unsuspecting future piñata-pillars.

Rabies is another viral disease that manipulates its hosts’ behaviour. Rabies causes acute encephalitis in warm-blooded animals, including humans. More than 55,000 people, mostly in Africa and Asia, die from rabies every year. There are three stages of rabies progression. The first is characterised by behavioural changes and is known as the prodromal stage. The second is the excitative stage. This stage is also known as “furious rabies” as the infected animal is exceptionally aggressive, hyper-reactive and will bite with little provocation. The virus is present in the nerves and saliva and as such the route of infection is usually, but not always, by a bite. With the encephalitis induced aggression and biting, the virus’ manipulation to aid its spread becomes clear. The third stage is the paralytic stage (due to motor neuron damage) which is followed by death.

The excitative stage of rabies is the example we’ve seen that is most similar to our zombie virus and in fact in the film the zombie pandemic (a good name for a band) is initially mistaken for an outbreak of rabies. So could a virus cause the changes seen in World War Z and cause a zombie pandemic with Brad Pitt staring concerned across various international scenes? Probably not, but parasites and viruses can certainly manipulate their hosts behaviour in a variety of subtle and not-so-subtle ways. Although ultimately it might be preferable to have your emotions and behaviour manipulated by watching a film. Panic Room is OK.

On The Origin Of Species: The Musical

The curtains go up. On the Origin of Species, published on 24 November 1859 by Charles Darwin is considered (correctly I would argue) to be the foundation of evolutionary biology. Its original full title was On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life which was later changed around 1872 to the shorter, The Origin of Species. It was perhaps felt that “the preservation of favoured races” sounded dubiously racist when in fact this wasn’t what the title was referring to at all. Of course the last thing anybody would do is falsely co-opt evolutionary theory to promote their own despicable and prejudice agenda. Right?

Darwin’s book introduced the scientific theory of natural selection. I am aware of the excellent work of Alfred Russell Wallace and you should definitely watch Bill Bailey’s brilliant TV series on the topic. However I’ve probably got enough work on my hands tenuously claiming that one set of original prose about natural selection should be a musical, without throwing Wallace into the mix. Notable in that it was not written specifically for a scientifically literate audience, The Origin of Species methodically and eloquently sets out the evidence and arguments for  the theory that the diversity of life on Earth arose by common descent through a branching pattern of evolution.  All any book by Dan Brown can say is that it’s thoroughly absorbent. It is not too much of a leap to say that modern evolutionary theory is the unifying concept of the life science and that little in biology makes sense without it. It’s a good theory.

Is the theory of evolution so good however that it can’t be improved by singing? Musical theatre as an art form combines songs, spoken dialogue, acting, and dance to communicate a story and its emotional content. It’s a bit popular. 12.27 million tickets were purchased for Broadway musical shows in 2007-2008. In 2007 total ticket revenues in Central London in the major commercial and grant-aided theatres were £469.7 million. Musicals are not just popular in theatre. Les Misérables, as a film aided by the singing of Anne Hathaway and Hugh Jackman while Russell Crowe was also there won 3 Oscars and earned £8.1 million in its opening weekend in the UK.

Just because something is popular though doesn’t make it good, he typed realising he’d already used his Dan Brown reference. Popular UK sitcom My Family anyone? Things could always do with a bit of added science and I would definitely watch a musical about evolution. Additionally there is some evidence that music can aid with learning as well as being useful in studying the brain’s natural plasticity. The Origin of Species: The Musical then seems like an ideal form of science entertainment. Primarily though I just thought it would be a fun idea to think and write about. So without much further ado, introducing The Origin of Species: The Musical!

Introduction

The introduction mainly establishes Darwin’s credentials as a naturalist.

Song: Naturalist In The UK

I am a scientist
I am a naturalist
I know what moths I want and
I know how to get them
I wanna catch butterfly.

Chapter 1

Primarily deals with animal husbandry, plant breeding and selective breeding.  Darwin describes the astonishing diversity of pigeon breeds given that that they all descend from a single species of rock pigeon.

Song: Crazy Little Things Called Doves

These things, called doves, explained, no religion,
These things called doves , descend, from a rock pigeon,
Selective breeding!
To get these little things called doves.

Chapter 2 and 3

Darwin argues the arbitrary distinction between species and varieties with species merely being distinctive and well-established varieties. He then explores how varieties become separate species and introduces the concept of natural selection.

Song: Taxonomy And Variety

Taxonomy and Variety, work together, to help describe species
Side by side for example, defining different types of trees.

Chapter 4

Darwin further describes natural selection through the relationships of all living beings and the physical conditions of their environment.  He also proposes sexual selection to explain sexually dimorphic features such as lion manes, peacock tails and some bird song.

Song: Girls Just Want To Have Good Genes

I’m at home, make myself look fine
Mother nature says when you gonna pick a genetic line?
Oh mother dear I’ll pick the best suited ones
And girls they want to have good genes
And men just want to have good genes.

Chapter 5

Here Darwin discusses the effects of use, disuse and inheritance.

Song: Lamarck The Disproved Theory Sings

With untested thought proclaim:
Use it or lose it is the game.
Lamarck the disproved theory sings
This kind of inheritance isn’t a thing.

 Chapter 6

Darwin discusses the existence of intermediate forms and then whether natural selection could produce complex specialised structures. (It can.)

Song: Stuck In The Middle With Gills

Water to the left of me, land to the right
Here I am, stuck in the middle with gills.

Chapter 7

This chapter covers the evolution of instincts using experimental evidence from ants and honey bees.

Song: Ain’t No Hexagons

Ain’t no hexagons with bees gone
Ain’t no swarm with bees away
Ain’t no hexagons with bees gone
They don’t make that honeycomb
Anytime bees go away.

Chapter 8

In this chapter Darwin addresses the idea that species have special characteristics which prevent hybrids from being fertile and preserve separate species.

Song: Bonnie Facts Of Stock Breeding

Oh you’ll take the hybrid and I’ll take the within-species breed
And I’ll preserve the genome before you.

Chapter 9 and 10

Here we get a bit of rock and look at how the geological record appears to show forms of life suddenly arising, without the multiple transitional fossils expected from gradual changes. Darwin then easily explains this by exploring the science and relative rarity of fossilisation.

Song: You Are Not A Stone

But you are not a stone
You just decayed to goo
Conditions didn’t apply
For you to mineralise
So you are not a stone.

Chapter 11 and 12

The biogeographical evidence is explored and Darwin notes the importance of barriers to migration in the formation of species.

Song: Island In The Sea

Island in the sea
That is where we are
Something between
Half our species gone
Go on breed with me
We’ll start to adapt
And given some mutations, ah-ha
We’ll begin our speciation, ah-ha.

Chapter 13

Darwin observes that classification depends on grouping based on degrees of similarity.

Song: I Believe I Can Classify

I believe I can classify
Pick matching wings and classify
Using nature’s morphology,
To recognise homology.

Conclusion

At last we have the big finale where Darwin reviews the previous chapter and expresses his hope that evolutionary theory might produce revolutionary changes in many fields of natural history. It did.

There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

Now to get some musical skill, incorporate the differences between different editions of the book and write this!

Genetic Engineering: Build-a-Pope

“I’ll give you two reasons why this is a bad idea.”

I don’t know if you heard but recently Pope Benedict XVI resigned citing reasons of being old and declining health. Whatever the minimum levels of health required for popeing are, Pope Benedict no longer feels he has them. He is stepping down to allow a younger more dynamic Pope to replace him. But who will this new Pope be? As with all talent competitions there are some names already being mentioned as frontrunners. Names being mentioned include Cardinal Angelo Scola, Cardinal Arinze of Nigeria and that fox Cardinal from Dogtanian and the Muskehounds. One of those may not be correct. Additionally comedian Richard Herring has previously offered his services and more recently Dean Burnett in his popular Brain Flapping science comedy blog for The Guardian reckons he’d be a good choice. I have a slightly different suggestion. Build a Pope.

                Being the head of the Catholic Church has some pretty specific demands and it must be difficult for one human to fulfil them all while appearing wise and good. Cynics would say that most don’t try. In this age of scientific advancement I say we don’t have to put up with that. There is a shop whereby if you want a special bear or stuffed animal for someone and you want to build this bear from scratch then you can go to this shop and build a bear to your exacting specifications. I forget the name of the shop. These days we can incorporate the DNA of one species into another for useful effect. I say that rather than choose a likely flawed, elderly human for the job we pick which qualities we desire from other animal species and construct a better Pope that will last for years to come. That the Catholic Church don’t approve of genetic engineering, that this act of science is not technically possible in the form that I’m proposing it and that this is obviously a flippant excuse to make some badly thought out jokes while listing some facts about the natural world should be no barrier.

Shepherd

To Catholics the Pope is the successor to Saint Peter. According to Roman Catholics, Jesus (you’ve probably heard of him) named St Peter and subsequent Popes, as the “shepherd” and “rock” of the Catholic Church. I don’t know what a Venn diagram of shepherds and rocks would be of (except that the intersection would contain the Pope) but I do know that a rock doesn’t have DNA. As such we must select a shepherd from nature to construct our ideal Pope.

There is a type of ant which farms and herds aphids. Sadly Jesus did not name St Peter the “aphid herd” of the Catholic Church. As such I have chosen the Border Collie in its capacity as a dog selectively bred in the English-Scottish border region for herding livestock, especially sheep, to contribute to our Pope.

The part-Border Collie Pope may have to change his costume somewhat as there is some superstition about collies. Handlers avoid mostly white dogs due to the idea that sheep will not respect a predominantly white dog. And you know you’re in trouble when you’ve lost a sheep’s respect. Hopefully the church will be able to accommodate random, seemingly superstitious demands.

Ultimately the ability of the Border Collie to take direction when herding via voice and whistled commands as well as its herding instinct would certainly help the Pope in his shepherding duty. I don’t know who would be giving the voice and whistle commands. God probably.

Fisher

                One of the many pieces of jewellery the Pope has, presumably to consolidate his position in the rap community is the Ring of the Fisherman. The ring features St Peter casting his fishing net and symbolises the role of the apostles in being “fishers of men.” So as well as herding people the Pope has to be good at fishing for them. Many animals in nature are adept at catching fish because of not wanting to starve. I have opted to include the behaviour of the humpback whale to add this capability to our design-a-Pope.

The diet of the humpback whale consists mainly of krill and small fish. One feeding method used to catch small fish includes the amazing bubble net feeding technique. To accomplish this a group of whales swim in a decreasing circle while simultaneously blowing bubbles to encircle a school of fish. As the ring of bubbles shrinks the fish are confined to an ever-narrowing cylinder of bubbles. The whales then swim upwards through the cylindrical bubble net with their mouths open to swallow the trapped fish. This incredible act of cooperation could be an excellent addition to the make-up of our Pope. Also the image of a Pope encircling the Vatican, blowing bubbles to keep the visitors in for mass is a fantastic one.

Father

The word “Pope” is from the Latin for “father”. While the Pope himself is not literally going to be a father for obvious reasons, it would seem prudent to include some parenting tendencies so our Pope feels the need to look after his church.

To meet this need I shall include the parenting trait of the male Darwin’s frog. The Darwin’s frog is native to the forest streams of Chile and Argentina. The female of the species lays the eggs and the male guards them until they hatch approximately two weeks later. The male then takes the developing young to carry in his vocal pouch. Once the tadpoles have developed sufficiently they hop out of the adult’s mouth and swim away. It’s probably asking for trouble to ask the Pope to carry young folk around in his mouth but the example in nature is an interesting one and having the DNA of Darwin’s frog may make our Pope more open to the teaching of science or at least the concept of evolution.

Longevity

Popes don’t tend to last that long in general with the average reign being about 7 years. This is probably because when they become Pope the gentlemen in question already tend to be quite advanced in years. We won’t really have that problem as we are constructing our own Pope but it would still seem sensible to have one that will last a good long while. The bristlecone pines are the oldest single living organisms known. The oldest known living organism (which is non-clonal) is a bristlecone pine tree nicknamed “Methuselah” in California, USA. Methuselah has been aged by measuring core samples (in 1957) to be just under 5,000 years old. If we include this tendency for longevity in our Pope we should be getting good value for money.

Asexual/Radiation Resistant

Catholic priests aren’t allowed to have sex and the Pope is no different. Given the tendency of humans for religious wars and the terrifying prospect of nuclear weaponry it seems sensible to have a Pope that can survive high levels of radiation. Luckily there is a species we can incorporate into our Pope which can provide both these ideals.  The rotifers make up a phylum of microscopic and near-microscopic animals.  They are common in freshwater environments with some species surviving in saltwater. Bdelloid rotifers have reproduced without sex for many millions of years. So our part bdelloid Pope won’t miss it. There are no male bdelloid rotifers and females reproduce by parthenogenesis. Technically this would make our Pope female which isn’t permitted in Catholic dogma. However our Pope is a genetic combination of various species which is also previously unknown in this religion so hopefully we can get past this minor issue and move with the times. Also should the time come for us to need a new Pope we could just get ours to reproduce parthogenically. After all the Catholic Church were quite keen on that one virgin birth that time.

Bdelloid rotifers are also extraordinarily resistant to damage from ionizing radiation. Which is handy. Perhaps it can become a plot point if our Pope is included in the next Dan Brown novel.

Morality/Religion

                Perhaps I’ve been remiss in not focussing on the religion or morality of our new Pope.  It’s certainly difficult to find examples of religion in nature. B.F Skinner claimed to have found the route of superstitious behaviour in his behavioural experiments with pigeons but that isn’t (quite) the same thing. As such I guess we should have human DNA in the mix and hope that religion and more importantly human morality becomes a force for good in our Pope. In the very least the Pope is known as the Primate of Italy and humans are definitely primates.

Suggestions

Perhaps you’d like to contribute to this frivolous and illogical exercise. What species do you think we should use when we build a Pope? Don’t worry, it’s almost definitely not going to actually happen. They’ll probably just go with some Cardinal. Like always.