Saturday, 28 January 2012

Clocks make you fit, evolutionarily speaking

Yesterday I attended the Bitesize lunchtime lectures at UCL and once again really enjoyed both the talks. Andy Beale gave a great introduction to the body clock field and his own research using a blind cavefish to investigate the evolutionary importance of body clocks.

This was Andy's first public engagement lecture at UCL. His intro "why we should care about body clocks" had photos of Andy himself sleeping (sleep-wake cycle), in a plane (jet lag), and drinking alcohol at lunchtime (which will get you more drunk than in the evening). The audience were laughing and certainly engaged.

Andy uses jet lag as an example of how we can disrupt our body clock (C) Andrew Beale, 2012

Andy gave examples of many other species that have body clocks, from the parasite that causes malaria, to the sleeping lion. Andy's interest in body clocks stems from his interest in evolution, what is so advantageous about having a body clock that it would be found so universally in so many diverse creatures? Does the early bird catch the worm?

Evolution is driven by natural selection, Darwin's "survival of the fittest", and in this instance it can be concluded that "clocks make you more fit". Being able to predict the sunrise and sunset might make you more likely to catch your prey/avoid your predator, and therefore your likelihood of survival.

Andy is researching a cave-dwelling fish from Mexico, that has been isolated in caves for more than a million years, with no access to sunlight, and no knowledge of "time of day". Have these cavefish kept a body clock, which would be redundant in their natural environment?

One unusual advantage of these Mexican cavefish is in the surrounding rivers another surface-dwelling river fish can be found, which do see daylight. These sighted river fish have the same ancestor as the cave fish (before they went into the caves) so make a vital comparison.

A blind Mexican cavefish next to two river fish. They have the same common ancestor and apart from a lack of eyes and skin colour are still remarkably similar so can be used to study evolution. Credit to Richard Borowsky
A lot of Andy's research has looked at gene expression. To convey what this means he used an excellent analogy. If we think of DNA as book, and genes as words, gene expression is like speaking the words aloud.

Andy's results from the cavefish show that when put on an artificial day in the lab aquaria with light and dark cycles, their genes act like the river fish, with a body clock. However, when in constant darkness, like in the cave, they lose their rhythmicity, they are not using their clock. His conclusions so far suggest that despite cavefish keeping their clock, in their normal environment the clock is not active.

Questions from the audience asked whether there were any animals that were found in the wild kept in constant lightness. Andy had mentioned that at the poles animals might be exposed to constant light for certain periods of the year, but not throughout the year. Andy theorized that it might be possible on another planet, and that would be interesting to look at.

I look forward to seeing some of Andy's work on blind cavefish published. It looks like I have a tough act to follow for my talk on "Shedding light on Body Clocks and the Brain" on 23rd March.

Saturday, 21 January 2012

UCL researchers are mapping our happiness across the week

This week I went to the first of this term's UCL Bitesize lunchtime lectures, where early career researchers at UCL talk about their work. I particularly enjoyed the second talk by George MacKerron, inventor of the mappiness iPhone app. His research question is to understand how the environment influences our happiness (green fields vs city skyscrapers), but I was especially delighted when he also showed how his data is beginning to say when we are most happy.

The mappiness app can be downloaded for free for iPhone users from the app store

My previous post was about how researchers are using twitter to determine when we are happy - MacKerron's app goes one step further to answer when and where are we happy. Subscribers get random beeps throughout the day asking them about the feelings on a sliding scale, how happy/relaxed/awake they are. They also put in a small bit of info on their current activities. The GPS on the phone can tell the researchers where they are.

His app has some of the same limitations as using twitter: people have to have access to the internet at the specific time, so grumpy tube passengers at rush hour in London are not having their feelings aired. Also, he is only sampling iPhone users, who might already be happier than the rest of us (Declaration of Interest - I'm an android user myself).

However, his app does overcome some of the limitations of using twitter feeds. App users are not publicly publishing their opinions, so there is potential they will be more honest. They are also being asked specific questions at random times throughout the day when they are happy, whereas twitter users might only be able to tweet at certain times.

MacKerran has had a great success in collecting a vast amount of data using this app. His original goal was to get around 300 participants, but with a great app and a bit of media coverage he is now collecting data from over 40,000 participants.

So what results has he been able to crunch out of this enormous data set? Apparently, Monday isn't the worse day of the week, we are on average fractionally more miserable on a Tuesday. So all the hype about Blue Monday last week being the most miserable day of the year turns out to be just hype. There are plenty of other more miserable Mondays, and Tuesdays, in the year.

Mappiness shows that Blue Monday isn't as bad as it's hyped up to be. Link here

Like the twitter studies, MacKerran's results show we are happier on the weekends. However, conversely with the twitter study, his results show that we start the day a bit grumpy and trend towards getting happier as the day goes on (data not yet published). The difference in results could be down to a number of things, including the type of app users, and that the app is limited to UK users.

I really enjoyed MacKerran's talk and I'm looking forward to seeing his work published. It's great to see how technology can increase our understanding of body clocks, and it would be good to see more apps (for android users too) developed for this.

I would recommend the Bitesize lectures if you are in London on a Friday lunchtime wondering what there is to do for free. This term's schedule is here. Of particular note there will be two talks on body clocks, this Friday Andrew Beale is talking about blind cave fish, and later on in March 23rd I will be giving my first public lecture on using light to effect your body clock.