Melatonin, serotonin and whale kebabs.

Destination Iceland

Straight to the science

In  July 2009 I had the pleasure of visiting Iceland – in between disruptive volcanic explosions.

I had never been so far north on this planet before. I was exited to experience excessively long days (22/24 h of daylight), geothermal hot springs, and elves… Okay, maybe not elves – but if you were to find elves anywhere in the world it would be Iceland!

I was also keen to learn the correct pronunciation of Eyjafjallajökull – the annoying Icelandic volcano not just stuffing-up commercial flighs, but making life difficult for news readers across the globe.

So, my good friend Saerah and I hired a car and set-out on a 2 week adventure. Iceland is stunning. From the black sands of Vik to the glacial highs of Vatnajökull, to the vast lowlands that still look like molten lava,  this country is like no place I’ve ever been before. It was also empty – does no one live here?!

Our first stop was Reykjavik, the country’s capital, a quaint and colourful port town. For summer, it was cold, the temperature rarely rising above 10 degrees. However, the excessive day length made it all worthwhile. Before going to Iceland I was worried that I would not sleep, that I would have to block out the light from by bedroom – I purchased an eye mask in preparation! What I didn’t think about was how the light would make me feel. I was energized and happy, and when I went to bed I had no trouble sleeping: content and tired from a long day of play.

I felt exactly the opposite to the way I did in Sheffield, UK, during winter where the nights were endless. I went to work it was dark. I got home it was dark. I’d never felt such depression (plus, I was in Sheffield!).

The science of daylight and happiness

I knew this probably had something to do with melatonin – a hormone excreted by the Pineal Gland in mammals, the amount released into the blood stream increased at night and decrease during the day. It helps animals fall into a circadian rhythm (a 24-hour cycle that regulates biological and physiological processes within the body).

What I didn’t know was the relationship between melatonin and serotonin – a signaling hormone commonly associated with happiness and well being. Melatonin is made out of serotonin, so the more melatonin our bodies make at night, the less serotonin there is remaining. Because I was experiencing very little ‘night’ in Iceland I have a feeling that my serotonin levels were sky high. Woot woot!

This may be why I didn’t even question trying whale meat – despite my disgust in the overall process of whaling. I had decided that I couldn’t knock something until I’d tried it… thank you serotonin for providing me with an unbiased point of scientific clarity (perhaps all scientists should take a hit before designing experiments). Needless to say, I didn’t like whale meat at all. It was bitter and irony, and tasted like mean slaughter practices. My serotonin levels dropped.

Speaking of serotonin levels dropping, one would assume that rates of depression are very high in Iceland during winter with the lack of sunlight and the high conversion of serotonin to melatonin. Referred to as Seasonal Affective Disorder (SAD: possibly my most favorite aptly named acronym of all times), this is the medical label given to depression that is the result of seasonal change (melatonin and serotonin). Surprisingly, in contrast to other populations of similar latitude, the Icelandic people have a very low level of SAD – thought to be the result of an unknown genetic factor. Another example of evolution?

Having seen the Icelandic Eurovision entry for 2011 (below), I believe this people are indeed low on SAD. Their national entry is rather jovial, especially considering they are singing in memorandum of their dead friend.

Oh, and in case you’re wondering, I got some of the locals to teach me how to pronounce Eyjafjallajökull. It goes a little something like this:


Moisturizer, aliens and willy-willies.

Destination Australia

Straight to the science

In August 2011 I found myself in Central Australia. The purpose: not leaving inspiration to chance! You see, I am part of a travelling circus, a science circus, and we traverse the country delivering scientific theory, and slinkys, to rural and remote Australian kids.

This year, we were bound for Alice Springs – a part of this country that I was eager to experience. I spent my weekdays touring local schools and aboriginal communities, exploring the properties of slime, bubbles and balance. During my spare time I took much pleasure in jogging on red dirt tracks, scaling rocky outcrops and using my pervy (telefocal) lense to take intimate photos of unsuspecting native animals (below). I also became obsessed with moisturizing, the arid desert clime removing water from everywhere – including your person!

So many aspects of Central Australia  fascinated me – the extreme plants that survived with too much sunlight and not enough water (I can’t even keep a cactus alive at home); the traditional indigenous culture; the dried-up river beds. However, by far my most interesting Centralian find was the town of Wycliffe Well: UFO capital of Australia.

I didn’t event know Australia had a UFO capital, but there it was, in all its glory – three petrol pumps, a caravan park and excessive amounts of stereotypical alien paraphernalia. I thought to myself, wow, aliens sure know how to choose their holiday destinations: bugger Tokyo or the Great Barrier Reef, or Milford Sound, let’s stop into the middle of nowhere on the Asia-Pacific leg of our tour!

It then struck me that lots of UFO sightings seem to happen in the middle of deserts – or at least this is what X-Files has led me to believe. Do aliens like dry heat? Or, does dry heat do something to cause a UFO-spotting psychosis? Unfortunately, I couldn’t find any peer-reviewed research into this – clearly a gap in our knowledge that a PhD student needs to get onto. Its important.

Aliens aside, the dry desert heat causes a more, uhm, real atmospheric phenomenon to take place – the willy-willy. Now, I know what you’re thinking – that Kiri, using any chance she can to mention “willies”. Fair call.

But, before you judge, let us take a peak at several willy-willy images I captured during my travels.

Experiencing these meteorological events was much like that movie Twister, only with less Helen Hunt, and more stars.

As I was staring at the desert landscape, scattered with willy-willies left, right and center (I was a lucky girl that day), it occurred to me that I never see these in Canberra. But why?

The science of willy-willies

Luckily, I was not the first to ponder the cause of willy-willy formation, unlike the psychosis of UFO sightings. In fact, a team of researchers at the Monash University School of Geography and Environmental Sciences had done the same. Their observation of  557 willy-willies, made over a 20 day census period, showed that willy-willy frequency varies according wind speed and something called “temperature lapse rate”  which is essentially how much the temperature decreases in the air from the ground up.

The ground cover was also important – when surface cover was less dense, this produced more willy-willies (which doesn’t explain why we don’t see these more in Canberra, what with all the space).

Willy-willy formation was found to be restricted to wind speeds between 1.5 and 7.5 meters per second. To put this in perspective, the average wind speeds in Canberra are 1.3-2.2 meters per second. This leaves “temperature lapse rate” as the crucial player in the willy-willy game – the scientists at Monash measuring the essential willy-willy initiation rate to be  0.9 °C per meter. Canberra’s average lapse rate is 0.006 °C per meter, and that my friends is why there are no willy-willies in our nations capital.

For a slide-show summery of what causes willy-willies please see below.

Joshua trees, moths, and plant sex.

Destination United States of America

Straight to the science

In January 2009 I attended a reproductive biology conference in San Diego, USA. I flew across from Hannover, Germany, where I had been plugging away at the ol’ Ph.D.

I had a poster to present at the conference on quantitative mRNA expression in embryos from blah blah blah , but the main purpose of the trip was to play back-up to my friend and colleague, Simon, who was presenting a paper we had co-authored (and by that I mean he wrote it, and used my minimal input to produce a great publication with my name on it). Si had not been well, so in the event that he should pass-out prior to show time I was in the wing.

Yet despite our diligent foresight, Simon stayed upright and nailed the presentation. In the meantime, I sat back and maintained a state of slight inebriation – it’s what Tiggers/ PhD students do best.

Having contributed little to this conference, I needed an adventure, and Sea World was too expensive. My German college, Ulrike, felt the same way. We hired a car and drove from San Diego to LA. As we cut through the isolating and stunning Yucca Valley, it was here that I learned of the Joshua Tree (Yucca brevifolia).

Pictured above, this ridiculous plant stands out against the vast planes of the Palm Desert. Once described as “the most repulsive tree in the vegetable Kingdom,” by American explorer John C. Fremont, this is surprisingly not the Joshua Tree’s claim to fame.

In fact Bono, the lead singer of U2,  had obviously been charmed in a similar fashion to myself by this desert tree – so much so that he named U2’s fifth album after it (pictured right; Joshua Tree not shown here). As I do not have a fifth album, or a first for that matter, I’ll just have to blog about this bad boy… the tree, not Bono (you can find his official  blog at

Now, you need to understand that I’m not a plant person, so that mere fact that I even noticed something that doesn’t have 4 legs, a tail, and does poopie, means it must be interesting.

A little scientific literature search peaked my interest in the ol’ Yucca brevifolia even further. These trees not only survive a harsh desert lifestyle of extreme temperatures and scarce water, they also survive through the ages – some specimens thought to be up to 1000 years old.

However, its their sex life that I’m most interested in, you know, as a reproductive biologist.

The sex life of Joshua Trees 

The Joshua Tree was given it’s name by Mormon immigrants making their way across the Colorado River. To them, the tree looked like the biblical character Joshua, his hands stretched out in prayer, guiding the pioneers westward.

This tree may now be guiding Westerners towards pioneering research.

Let’s now talk about sex – the final promise in the title of this post – as the way Joshua Trees ‘do it’ is one of the most interesting things I’ve learned about this desert plant.

Joshua trees rely on moths to pollinate their flowers, and there are 2 different moths at hand to do the job: Tegeticula synthetica Riley and T. antithetica Pellmyr. Let’s call them moth A and moth B to keep things simple.

These moths (both A and B) are referred to as ‘pollen vectors’ as they transport pollen from one tree to another, using the plants flowers to complete their life cycle.

Depending on whether moth A or B do the dirty with a tree affects the overall floral and vegetative morphology (the way the leaves and flowers look) of the resulting offspring tree. In fact, there appears to be a direct relationship between the length of the moth’s ovipositor (the organ she uses to lay/ inject her eggs into the plant) and the part of the flower where she inserts said ovipositor. A classic example of where size does matter…

Let’s assume that moth A has a relatively long ovipositor and tries to pollinate the ‘wrong’ tree (with a small flower), it will damage the plants ‘bits’ by over penetrating it, resulting in null fertilisation.

Let’s assume moth B has a relatively short ovipositor and tries to pollinate the ‘wrong’ tree (with a big flower),  its ovipositor won’t penetrate the flower deep enough to fertilise.

Whether it was moth A or B that helped fertilise and produce the next generation of Joshua Tree then affects what moth will be able to pollinate it. Imagine if this was the case with humans – your parents would have determined who you could and could not reproduce with.

The Joshua Tree’s relationship with its moth (be it A or B) a classic case of co-evolution – two organisms evolving together for some greater purpose. However, what that purpose is in this example is yet to be explained.

For more on how trees ‘do it’ and co-evolution you can listen to Thomas Wallenius from the ANU talking about his PhD research:

Altitude sickness, garlic soup and mountain ponies.

Destination Nepal 

Straight to the science

In July 2010 I took a trip to Nepal. I had just submitted my Ph.D. and having used so much brain for this last feat, I wanted nothing more than a physical challenge. I wanted brawn.

It took very little convincing to get my friend Katie to come along. Like me, Katie has a thirst for travel, and gin. We decided on an 11 day trek along the Annapurna Circuit where we would climb steadily from 1000 – 5000 m in altitude.

Having both travelled to mountainous regions before – Katie in South America, and myself in Pakistan – the last thing we worried about was altitude sickness. A classic case of Hubris.

Our holiday started well. We somehow identified our local guide in the busy market place, much like a blind date. Our guide, a 20-something engineering student provided his service at a comparatively low cost to other guides, we would find out why a little later down the track, but for now his dashing good looks dashed any practical questions that we may have had at the time.

Days 1-5 were truly spectacular. Nothing could dampen our spirits, not even relentless rain that left our boots and socks and everything in our packs saturated each evening; or the uninviting toilets that provided little comfort for the diarrhoea-ridden Westerner; or the endless bowls of garlic soup that our guide force-fed us to warn off high altitude sickness (and vampires, and anything with a nose). Nope, nothing could bring us down, except somewhat ironically 2500m of altitude.

The symptoms came on slowly. Despite walking for 10 hours a day, our appetites began to fade. By day 6 we had vetoed garlic soup, much to our guide’s disappointment – he was now running around trying to find yak cheese and crackers – the only thing his increasingly precious Western gals would stomach.

Then the headaches set-in, accompanied by a strange insomnia and mood swings that saw Katie and I walking hundreds of meters apart, the Himalayas had suddenly become too small for the both of us.

By day 7, about 3000m, I started to level out. My head gently throbbed along with my iPod, but in a constant and familiar way. Katie on the other hand had taken a turn for the worse. By the time we reached 3500m it was clear we had a problem. Katie was vomiting uncontrollably. Her headache had worsened and was causing double vision and blind spots. An extreme fatigue, and dehydration, meant she could no longer move easily.

It now became apparent why our guide came cheap – he had no experience with white girls and mountains. As lovingly as he tried to resolve the situation, it was obvious that this had not happened to him before. As the sun sank, so did the realisation that we had to get Katie off this damn mountain – I knew this only by having read the Dangers and Annoyances section of my sodden Lonely Planet. The only cure for altitude sickness was to remove the altitude.

However, with Katie unable to walk getting off this hill was going to be an issue. There were no roads, cars, motorbikes, planes or anything with an engine on this side of the Annapurna. We needed a horse, and fast.

Twenty minutes of negotiation, 2 cups of bitter tea and a Nepalese years salary, and we had a horse. We stacked Katie and her pack on the horse. I gently rocked her – she seemed stable, and in a position that allowed the occasional vom without chocking (thank you Surf Lifesaving Australia for making me aware of the importance of clear airways). We set off as the sun set, retracing the days work. I walked behind Katie and her flatulent horse, using a $5 head torch to illuminate the Himalayas.

Six hours later, approaching midnight, we had descended to around 2700m and Katie had made a miraculously recovered. All her symptoms had vanished. She looked remarkably fresh, ready to go again. How did this altitude sickness thing work?

The science of high altitude sickness 

So, here’s the thing – no one really knows how altitude sickness disrupts normal bodily function, resulting in the symptoms experienced by Katie. However, several theories are starting to be explored in more depth. What is known is that reduced oxygen levels at high altitude results in hypoxia – a dangerous condition where the body is deprived of adequate oxygen for normal function. It is hypoxia that causes altitude sickness – but how? And, why does it only effect some people? Surly our local guide uses oxygen the same way we do?

It has been suggested that hypoxia disrupts the blood brain barrier, a specialised part of our anatomy that controls what goes in and out of the brain via the blood. This disruption causes the brain to swell, and hey presto – the next thing you know you need a horse! Well, some people need a horse, others seem more biologically equipped to deal with the change. A defensive anti-inflammatory response has been measured in people that are resistant to altitude sickness, as has a change in the permeability of the blood brain barrier (becoming less permeable in altitude sickness resistant individuals).

At this point I know what you are thinking: “how do I know if I will need a horse the next time I attempted to conquer Everest?” Well, I’m happy to report that scientists have been thinking the same thing, sort of. In fact, a paper published last month (August, 2011) looked at biological markers that may help us predict the likelihood of developing altitude sickness. If your lactic acid levels reach a certain threshold (>2 mmol/L) or your oxygen saturation levels decrease by more that 10% after a 6 min walk, then start saving for that horse. The core reason for altitude sickness lies in our genetic code.

Alternatively, you could dose yourself with dexamethasone, a common altitude sickness preventative drug that promotes the anti-inflammatory effect that fights altitude sickness, or acetazolamide a drug that acidifies the blood, driving ventilation that increases oxygen saturation of the blood.

To get a better idea about the effects of altitude, I spoke with Prof Chris Gore from the Australian Institute of Sport. Chris is using the effects of altitude to improve athlete performance (part 1 of interview). However, his insights into the physiological effects of altitude also help explain Katie’s response to altitude (part 2 of interview).

Interview with Chris Gore Part 1: Altitude and Athletes

Interview with Chris Gore Part 2: Altitude and Katie