Why do dogs wag their tails? A new insight.

Observe the majestic pug his natural habitat, the flower garden.
Observe the majestic pug in his natural habitat, the flower garden.

If there are two things that pique my interest in life, it’s Biology and dogs (specifically pugs). So imagine my delight when I saw that there was an actual research paper in Current Biology all about dogs [1]. The study showed that dogs can communicate their emotions with other canines through tail wagging. It has already been shown that tail wagging to the left is linked to anxiety while wagging to the right is linked with more positive emotions [2]. What this new study showed was that dogs can actually respond to the left- or right-tail wagging of other pooches. It is thought that this behaviour is linked to the processing of different social queues in different sides of the brain [1,2].

This is a pretty relaxed Basset Hound.
This is a pretty relaxed Basset Hound.

In this study dogs were shown movies of other dogs wagging their tails more to the left or more to the right and the viewing dogs’ heart rate and behavioural reactions were recorded. The same experiment was also repeated with a silhouette of another dog, to reduce other social queues like facial expression. The results showed that the heart rates of dogs shown left-wagging went up, a sign of anxiety, while dogs shown right-wagging had a lower heart rate and relaxed behaviour.

Interestingly, when the canines were shown a movie of a still dog they had higher levels of anxiety than when shown a movie of a right-wagging dog. The authors proposed this may be due to confusion as the dogs tried to work out what the dog in the movie was doing or that this might be linked with human responses to neutral faces: in experiments where people were shown faces with neutral expressions they tended to assign negative emotions to them [3]. Perhaps like the humans, these were pessimistic pooches.

PutamenThese results are interesting in terms of understanding the nuances in social communication between dogs but also hint at something relatable to other animals. They also  support the notion that processing of certain social situations can favour one side of the brain over the other. This may well help us understand our own brains better and aid research into how the brain responds to different emotions. All I know is, there should be more serious scientific studies that have this in the supplementary figures…

http://www.sciencedirect.com/science/article/pii/S0960982213011433

 

References

[1] Marcello Siniscalchi, Rita Lusito, Giorgio Vallortigara, Angelo Quaranta, Seeing Left- or Right-Asymmetric Tail Wagging Produces Different Emotional Responses in Dogs, Current Biology, 2013.

[2] Claire L. Roether, Lars Omlor, Martin A. Giese, Lateral asymmetry of bodily emotion expression, Current Biology, Volume 18, Issue 8, 22, 2008.

[3] Eun Lee, Jee In Kang, Il Ho Park, Jae-Jin Kim, Suk Kyoon An, Is a neutral face really evaluated as being emotionally neutral?, Psychiatry research, volume 157 issue 1, 2008.

By Liz Granger
@Bio_Fluff

Humans – Why Are We So Gross?

Our bodies, all in all, are pretty impressive. We’ve got big brains, mighty muscles and intricate insides. Human bodies are remarkable, finely tuned machines. Unfortunately these machines have a lot of by-products. We make sick, snot, pus and poop. There are no two ways about it, these things are pretty disgusting. But what are they, what are they made from and why have our bodies evolved to make so much unpleasant stuff?

Read on if you have a strong stomach and you’re not currently eating. This isn’t one for the squeamish.

What is Sick Made Out Of?

VomittingSick is just undigested food and liquid from your stomach mixed with gastric acid. The gastric acid is what makes throwing up hurt. It is a mix of HCl and KCl that the stomach uses to kill microbes present in food and has a low pH (around pH1). Food is churned around in the stomach for a bit with a few digestive enzymes and the gastric acid. Once the food is nice and slurry-like it passes into the intestines for absorption.  When you’re sick, whatever hasn’t made it to the intestine does a reverse anti-gravity manoeuvre and comes back up. Lovely stuff.

 

What is Snot Made Out Of?

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Image Taken from: http://www.flickr.com/people/17642817@N00

Snot is infected mucus. Mucus is constantly secreted by the delightfully named Goblet cells that adorn your airways. Mucus is largely made out of proteins with massive chains of sugar attached. These molecules cling on to water, which gives mucus its slimy consistency. Most of the time mucus is a good thing, trapping dust and microbes. The cells of the airways are covered in hair-like structures that can then waft the dust-microbe-mucus combo out of the airways and down into the stomach where it can be digested.

This all goes a bit awry during a cold when the cells in your airways get infected with cold viruses and the mucus becomes snot. Your immune system declares war on the virus but unfortunately during the battles, there are a few casualties to your own cells. Some of these are white blood cells that can explode to release chemicals, which kill invading nasties. One of the thing that spills out of these exploding cells is a green coloured anti-bacterial enzyme called MPO. So green snot isn’t so bad, it just means your white blood cells are doing their job and fighting infection.

What is Pus Made Out Of?

pus 2Pus isn’t too dissimilar to snot as it’s made out of a lot of debris from battles between the immune system and infection. Pus is essentially the remnants of all the white blood cells that have rushed to a site of infection and died fighting the invading microbes. Pus isn’t harmful, it’s a sign your body has been fighting infection the way it should and eventually the body will clear pus from sites that were infected. If pus doesn’t clear, it may be a sign your body is struggling to fight an infection.

What is Poop Made Out Of?

Yep, the grossest of all gross things. We all know what poop is, but what is it actually made from? Well, unsurprisingly undigested food makes up a large proportion. Dietary fibre – the stuff that keeps you regular – is the stuff you can’t digest and gives your poop a bit of form. So that’s good. There’s also a LOT of bacteria in there, which along with methane, causes the smell. It’s brown because of bile, which is a yellowing-green substance secreted by the gallbladder to help digest fat. When bile passes through the digestive system it changes colour and turns brown. The gallbladder is situated inside the liver, so if the liver gets swollen and inflamed it can block the bile duct and this results in poop that is white as a sheet. So if your poop looks like it’s seen a ghost, I suggest you see a doctor.

So there you have it – that is why human beings are gross.  It’s quite possible we’ve evolved to find these things disgusting as a way to avoid illness and infections.  Whatever the reason we find them off-putting, they are all just part of being human.

Congratulations if you made it the whole way through the post – you’re made of strong stuff.

Post by Liz Granger

Twitter: @Bio_Fluff

Basic Research – What’s the Point?

I am what is known in the research trade as a ‘basic’ researcher. It’s not that my work is simple. What basic research means is that the work doesn’t have any immediate real world application.

In some people’s eyes that means it’s not useful, or ‘research for the sake of research’. In my opinion it’s pretty exciting – I look at how and more importantly why things move around inside cells. Intrigued? Read about it here.

These scientists might be doing basic research, just don't ask what's in the tube.
These scientists might be doing basic research, just don’t ask what’s in the tube.

Some research has direct applications – researching new drugs, new technology, the effect of various factors on health and the environment, you know – ‘useful stuff’. The thing about all of that research is that it has its foundations deeply rooted in knowledge gained from basic research.

Now don’t get me wrong I like the stuff that comes out of ‘useful’ research. I’m keen to find out how many rashers of bacon I can chow down on before I’ll get cancer. If I get ill I’d definitely want a new drug that could treat me. I’m eager to find out how much we’re screwing up the planet. Research that translates to the real world is awesome. I just think basic research should get more credit, or at least less flack, for contributing to science and our understanding of how things work.

Most importantly, basic research deserves to get funding. Not just because it’s interesting, but because we don’t know what useful things may come out of it one day in the future. If BuzzFeed has taught me anything, it’s that a point is always made best in the form of a list. So here are my ‘Top 3 Basic Research to Real World Breakthroughs ’. Catchy name, no?

1.       The Structure of DNA

DNA_double_helix_45Raging misogyny and racism aside, if Watson and Crick hadn’t taken Roselyn Franklin’s data without her permission* and worked out the structure of DNA…well someone would have probably worked it out eventually. But that doesn’t take away from their combined genius in solving the structure. They also did ground breaking work to discover how genes in DNA are made into protein. Intellectually speaking they were/are pure brilliance.

Now, this may all seem applicable to the real world in the first instance but when you think about it, Watson and Crick wanted to know the structure of DNA and how it worked purely for the knowledge. When they made this humanity-changing intellectual breakthrough, they had no idea that one day our knowledge of DNA would lead to huge leaps forward in medical diagnosis and treatment, or for that matter the ‘Who’s the daddy?’ paternity tests of Jeremy Kyle. The latter is more important. Obviously.

2.       The discovery of cellulose.

800px-Plastic_objectsCellulose; everyone’s favourite plant based, un-digestible polysaccharide. I’d guess when Anselme Payen discovered this polymer in 1838 he was just really psyched to find out more about the molecules in plants. I’d certainly be surprised if he envisioned that one day cellulose would pave the way for polymer science and one of our greatest inventions – plastic. Don’t think plastic is terrific? Look around you– how much stuff is made out of plastic? Plastic has made manufacturing easy. The discovery of cellulose as a natural polymer aided polymer research in years to come, most notably the Nobel Prize winning work of Hermann Staudinger. In turn, understanding polymers provided a means to produce many different and useful types of plastic that we can use to make stuff cheaply and easily.

3.       Radioactivity

Radioactivity_symbolMarie Curie. She was one seriously cool lady. Alongside her also very cool husband, Pierre, she discovered radioactivity.  After years of toil they purified and discovered polonium and radium. The research was unquestionably driven by the desire to simply understand what radioactivity was. The work has been instrumental in helping us understand basic physics at an atomic and sub-atomic level. Despite this, the research Marie and Pierre did has given rise to many real world changes including nuclear energy, medical treatments such as radiotherapy to treat cancer, alongside uses in sterilisation of food and other fields of research.

So there you have it, my ‘Top 3 Basic Research to Real World Breakthroughs ’. But there have been way more. What have I missed out? What would go on your list? Let us know in the comments below.

Post by: Liz Granger

Twitter: @Bio_Fluff

*This is only one side of the story. Read more about the dynamic between Rosalind Franklin, her colleagues and Watson and Crick, here and here.

Fighting jet lag – a simple case of wearing more layers?

Pioneering research has found that one of the best ways to beat jet lag may be by wearing more layers, sitting by a fire and having plenty of cups of tea. Scientists have found that our biological clocks are driven not only by light, but also by our body heat.

fireImagine you’ve been on a relaxing holiday. You’ve done nothing more than catch some sun, top up your tan, and sip cocktails on the beach. Why, despite the relaxing nature of your holiday do you return feeling more tired and fatigued than when you went? It is all to do with jet lag.

After a long-haul flight that crosses over many time zones, you can feel excessively tired and nauseous, with poor concentration and memory. Usually the more time zones you cross, the more severe these symptoms.  It also takes longer to recover, the longer the flight.

So why do we get jet lag?

We suffer from jet lag because of disruptions to our internal body clock which regulates things called circadian rhythms. These rhythms control many of our bodily functions and behaviours such as body temperature, appetite, hormone release and sleep patterns. They are controlled by a part of the brain called the SCN – the suprachiasmatic nucleus, located just above the roof of our mouths.

Circadian_rhythm_labeledOur body clock is synchronised to our environment using light signals, which signal to our brain what time of day it is.  During long haul travel, the cells in the brain’s ‘body clock’ become confused by the change in the light and act out of sync with each other. This is the point where we experience symptoms associated with jet lag.

Scientists have known about jet lag for a long time, but we know little about how to treat it successfully.  If you look on the internet you can find numerous sites giving tips on how to beat jet lag- or at least improve the symptoms. From my own experience, every time I’ve travelled to America and tried some of these, they have rarely touched the surface.

If you want to avoid jet lag the advice is to establish a new routine so that you eat and sleep according to the time zone you’re in, avoid napping during the day, and making sure you get as much natural light as possible. Research has shown that experiencing light during the evening causes a delay in our body clock meaning our bodies rhythms move later in the day. If we are exposed to light during the early morning, our clock becomes advanced and our rhythms start earlier in the day.

This stuff is all pretty old news. The link between the circadian clock and temperature is, on the other hand, altogether remarkable.  Scientists have found lots of evidence that point towards our biological clocks being driven by our body heat. Fruit flies exposed to drastic changes in temperatures exhibited changes to their body clock. They found that cells in the back of the brain called ‘dorsal clock cells’ were important in synchronising the body clock at warmer temperatures. Cells at the front of the brain -‘ventral clock cells’, synchronised the clock at cooler temperatures.

These findings may be key in helping us defeat jet lag by easing our body clock back into its status quo. It may be as simple as piling on layers of chunky jumpers, scarves and hats if you come from somewhere blisteringly hot, to be plunged into a cold climate. Vice versa, stripping down to as little clothing as possible may help battle jet lag if returning from somewhere cold. It’s all about easing our bodies back into its normal routine; not plunging straight into the deep end.

Post by: Samantha Lawrence

The Science of Sleep – You snooze you lose?

My top ten favourite things to do are as follows:

1) Eatsleep and food
2) Sleep
3) Snack
4) Snooze
5) Lunch
6) Nap
7) Chow down
8) Dream
9) Pig out
10) Have a kip.

Now, I know why I like to eat – food tastes good. Also, if we’re going to be all ‘sciencey’ about it, humans have evolved to enjoy eating as we need the nutrition to survive. But why do we sleep? The answer is no one really knows. However, anyone who has ever pulled an ‘all nighter’, suffered insomnia or done a PhD can tell you sleep is certainly necessary. A lack of sleep leads to difficulty concentrating, an inability to focus and a lack of motivation which gets progressively worse the less sleep you get. And the only way to rectify this? To get some sleep.

It’s tempting to assume that we sleep to save energy, but this isn’t really the case. In fact we don’t save that much energy sleeping compared to just laying still. However, one thing we do know is that sleep is actually vital for the brain. That would explain the difficulty concentrating when you don’t get enough of it.

dog sleepingThere are two main types of sleep: rapid eye movement (REM), which is when we have our most unusual disjointed dreams and non-rapid eye movement sleep (NREM) which usually brings fewer, more mundane, dreams. Unsurprisingly you can tell when someone is in REM sleep because their eyes dart around, whilst the eyes are relatively still in NREM sleep. Throughout the night we cycle in and out of these sleep stages (around 2-4 cycles every night), with the vast majority of sleep comprised of NREM. Scientists can monitor what stage of sleep people are in by looking at their brain wave (EEG) activity.

Yes, apparently brain waves are an actual thing. I’m not trying to be funny here – I genuinely had no idea these were real until earlier this week. I thought it was a saying like ‘being on the same wavelength’. Who knew? Everybody else in the world it would seem.

When brain cells want to communicate with each other they use electro-chemical signals which can be detected by neighbouring cells. Brain waves are simply the combined ‘firing’ of groups of brain cells. This collective ‘firing’ creates a voltage change large enough to be detected by electrodes placed on the scalp and this is the basis of the EEG. Peaks of synchronised firing are generally followed by periods of silence before moving to another peak, forming rippling electrical waves – brain waves.

During REM sleep brain waves are low amplitude, which means fewer cells are synchronised therefore producing a smaller signal. Waves which do occur in REM are also fast, meaning the cells are firing off electrical pulses more frequently. This pattern is very similar to the EEG signal seen when we’re awake.

Fun fact about REM: Species of animals with larger brains seem to require a higher percentage of REM sleep compared to NREM sleep. With tit-bits like that you’re sure to have as many friends as me! Two’s a lot right?

Anyway, REM is thought to be important for forming new spatial memories (like remembering how to get to that new bakery in town which sells those gorgeous pastries). Scientists also think that REM sleep may be required for the development of new brain cells in the memory forming region of the brain (the hippocampus). This is one of the processes which may be necessary for laying down new memories. woman sleepinh

NREM sleep can be broken down into three stages. During the first stage, a state somewhere between sleep and wakefulness, brain wave activity starts to slow and switches to the high amplitude slow waves which characterise NREM sleep. During the second stage ‘spindles’ can appear. These are groups of large amplitude, irregular spikes in the EEG. It is thought that this high-amplitude activity represents periods when large areas of the brain are synchronised. This may be the perfect time for memories to be transferred between brain regions and may facilitate the incorporation of new memories into older existing ones. Interestingly schizophrenics show less spindle activity, but like many aspects of sleep, it isn’t really clear why. In the final stage, the brain has fully switched into slow wave. It is thought that during this stage new memories form. Slow wave activity is linked with the ability of brain cells to make new connections and ‘prune’ out old ones.

There is so much that absolutely no one understands when it comes to sleep. All in all I think this makes this topic incredibly interesting and, yeah I’m just going to say it – exciting. Ultimately though I’m quite happy that scientific research has unquestionably disproved the phrase ‘you snooze, you lose’.

Post by: Liz Granger

Twitter: @Bio_Fluff

References

Roth TC 2nd, Rattenborg NC, Pravosudov VV. (2010) The ecological relevance of sleep: the trade-off between sleep, memory and energy conservation. Philos Trans R Soc Lond B Biol Sci 27;365(1542):945-59.

Fogel S, Martin N, Lafortune M, Barakat M, Debas K, Laventure S, Latreille V, Gagnon JF, Doyon J, Carrier J (2012). NREM Sleep Oscillations and Brain Plasticity in Aging. Front Neuro, 3:176

Saletin, J.M.; Goldstein, A.N.; Walker, M.P (2011). The Role of Sleep in Directed Forgetting and Remembering of Human memories. Cerebral Cortex21, 2534–2541

Ferrarelli, F.; Huber, R.; Peterson, M.J.; Massimini, M.; Murphy, M.; Riedner, B.A.; Watson, A.; Bria, P.; Tononi, G. (2007). Reduced Sleep Spindle Activity in Schizophrenia Patients. The American Journal of Psychiatry164, A62