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In the event of a zombie apocalypse, making your way to the Rocky Mountains in the US might be your best bet for survival.

A team of scientists at Cornell University have simulated a zombie outbreak in the US as a novel approach to studying infectious disease.

Using statistical mechanics, the team led by Alex Alemi simulated millions of interactions between zombies and humans to predict the pace at which a fictional zombie virus might spread.

'We build up to a full scale simulation of an outbreak in the United States, and discover that for realistic parameters, we are largely doomed,' said the researchers in their paper.

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Densely populated cities would fall to a zombie outbreak in a matter of days, according to a simulation built by researchers at Cornell University as a fun way to approach statistical mechanics and disease modelling (scene from film 28 Days Later pictured)  

While the study focuses on an imaginary disease, the techniques used are useful in modelling the spread of real infectious diseases.

Cities like Los Angeles and San Francisco would become overrun with zombies within days, with less densely populated rural areas lasting a few weeks.

But it would takes months for the infected to reach the northern Rockies, making the mountains an ideal hiding place to escape the undead hordes. 

'At their heart, the simulations are akin to modeling chemical reactions taking place between different elements and, in this case, we have four states a person can be in—human, infected, zombie, or dead zombie—with approximately 300 million people,' Alemi told Phys.org.

Run to the hills: it would take months for the infected zombies to reach the Rocky Mountains in the western United States, making the mountain range the best place to escape to. The model simulated millions of interractions between infected zombies and humans

The simulation has built in randomness: interactions between zombies and humans can go either way.

Sometimes the zombie bites the human victim, infecting them, and sometimes the human is victorious, living to fight another day.

In this way, each interaction is treated like a radioactive decay, allowing the researchers to calculate the rate of spread throughout the United states where each event - for example the fall of a city - can affect the rate of spread.

In fictional accounts, 'if there is a zombie outbreak, it is usually assumed to affect all areas at the same time, and some months after the outbreak you're left with small pockets of survivors,' explains Alemi. 'But in our attempt to model zombies somewhat realistically, it doesn't seem like this is how it would actually go down.'

'Given the dynamics of the disease, once the zombies invade more sparsely populated areas, the whole outbreak slows down—there are fewer humans to bite, so you start creating zombies at a slower rate,' said Alemi.

If the model was applied to the UK, the Scottish highlands might be the best equivalent to the Northern Rockies with a very low population density and similar terrain.

Nightmare: If the model was applied to the UK, the Scottish highlands might be the best analogue to the Northern Rockies with a low population density and similar terrain (scene from the Walking Dead pictured)

SIX TIPS TO SURVIVE THE ZOMBIE APOCALYPSE 

Don't fight: Zombies wouldn't have the neural responses to care about pain, so unless you could shoot to kill, it would be best to run for it.

Keep quiet: Zombies with CDHD would have very little memory and poor concentration, so if you hid, something else would likely capture their attention, keeping you safe.

Distract them: Damage to zombies' posterior parietal cortex would mean that they couldn't concentrate and would be at the mercy of whatever grabs their attention. Try fireworks for a quick getaway.

Copy to survive! Zombies wouldn't be able to recognise faces so they identify each other by movements and sounds. 'If confronted with a herd of the undead with no clear avenue of escape, do what Shaun and his friends did in "Shaun of the dead" – act like a zombie, the experts said

Out-run them: This only would only work with CDHD-1 zombies, who would only be able to lumber along clumsily.

Don't try reason: 'CDHD presents with a massive dysfunction of the language circuits in the brain. This means that zombies can't understand what you're saying, nor can they talk back,' the neuroscientists warn. Their 'fight' reaction would dominate, leaving you pleading with an angry hungry zombie.

Mimic them: Zombies wouldn't be able to recognise faces so they identify each other by movements and sounds. 'If confronted with a herd of the undead with no clear avenue of escape, do what Shaun and his friends did in "Shaun of the dead" – act like a zombie. Do it with enough accuracy and you can wander through the herd undetected,' Professors Verstynen and Voytek say.

Using fictional diseases like a zombie outbreak can be a fun introduction to the complicated maths of disease modelling, according to Alemi.

If given more time, Alemi said the team would add more complicated social dynamics, including air travel, evacuations and advance warnings, giving the humans a better chance to prepare. 

The group will present their findings at the 2015 American Physical Society March Meeting, on Thursday, March 5 in San Antonio, Texas.

The simulation was inspired by the graphic novel World War Z - which the 2013 movie starring Brad Pitt was based on - during a graduate statistical mechanics class at Cornell University.

The ultimate weapon for the Zombie Apocalypse (related)

ZOMBIISM IN NATURE: BRAIN CONTROL IN ANTS AND HUMANS

If you suppose that zombies are created by a supernatural version of mother nature, it appears she is very clever, because the specific brain changes mean that the consciousness and free will of zombies would be highjacked, but their brain functions needed to hunt, would be preserved.

'Random brain damage does not result in brain damage,' the authors say. 'This means the infection spares the neural tissue that's needed for spreading the infection,' when one zombie bites or eats another human.

'Areas necessary for anger, hunger, smelling, seeing, biting and other basic movements remain intact, while obliterating the areas that produce complex thoughts, make proactive decisions or consciously form and recall memories.'

Zombiism can be seen in the natural world: A fungus called Cordyceps takes over the minds of insects. It controls the mind of its host ant, before killing it and releasing spores through its body (pictured)

While such behaviour is theoretical in humans, there are plenty of examples of zombiism in the animal kingdom.

A fungus called Cordyceps takes over the minds of insects. It starts life as a spore that lands on an ant, which slowly stops performing its usual role in a colony, so it's thrown out by more diligent worker ants.

The fungus takes control of the ganglion cells that make up the insect's brain, forcing it to bite down hard on a leaf with its mandibles. At this point, Cordyceps kills its host, causing a stalk to erupt through the ant's head and release more zombie spores to secure the fungus' grisly existence.

Similarly, a tiny thorny-headed worm of the phylum Ancantho cephalia, burrows into the brain of a tiny crustacean, Gammarus lacustris, to take control of its nervous system. It forces the crab to swim towards the ocean's surface where it will be attacked by predators.

In humans, tapeworms can make its way into the brain to change our behaviour, but a microbe called Toxo plasma gondii (T.gondii) goes a step further.

Found in cat faeces, it can infect humans and stop them fearing risky behaviour, with tragic results.