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Humans don't have a monopoly on being smart: many other animals, including birds, can solve problems and even make and use tools.

But does it always pay for animals to be brainy or are there hidden costs?

A recent study of great tits, published in Current Biology, gives an insight into  the trade-offs between problem-solving abilities and other traits. The work was conducted by Ella Cole of Oxford University's Department of Zoology and Julie Morand-Ferron and led by John Quinn. I asked Ella about birds, brains, and strategies…

OxSciBlog: What makes great tits good for studying problem-solving?
Ella Cole: Great tits are well-known for their ability to problem-solve in order to find food, ranking among the top 20 most innovative avian species. This ability to solve novel problems or find new food sources may be one reason why great tits are able to survive in such a variety of different habitats.

In our work with the tits, we try to establish whether good and poor problem solvers differ in how they forage in the wild and how successful they are at reproducing. Our problem solving trials are carried out in captivity under standardised conditions. We therefore need to test large numbers of individuals as we cannot be certain how many birds we will be able to find again once they are released back into the wild.

Great tits are an excellent study species because they can be caught in large numbers, easily adapt to captive conditions and  take to nest boxes allowing us to monitor their foraging behaviour and breeding success in the wild.

OSB: What links did you find between problem-solving and successfully raising offspring?
EC: We found that females that could problem-solve in captivity laid more eggs than their non-solving counterparts when released back into the wild. If their nests did not fail, these solvers also fledged more chicks than non-solvers.

Even though the quality of food fed to chicks did not differ between solvers and non-solvers, solvers had much smaller foraging ranges and foraged for less time each day than non-solvers, suggesting they may be generally more efficient at finding food.

Interestingly though, female problem-solvers were more likely to desert their chicks than non-solving females, leading to no overall fitness difference between solvers and non-solvers. These findings provide the first convincing evidence that problem-solving abilities may influence reproductive success in wild populations.

OSB: What do your results tell us about the costs of being smart?
EC: Our finders suggest there may be costs as well as benefits to being smart. We find that problem solvers are more likely to desert their nests, which is a common adaptive behaviour amongst birds in response to unfavourable conditions.

Although their offspring will die, deserters can preserve their resources for themselves and therefore breed again when conditions may be more favourable. We show that desertion in our population may be a direct response to trapping by field workers – a procedure that is carried out in order to establish the identities of breeding birds (via reading their unique leg bands).

It is likely therefore that solvers may be more sensitive to human interference at the nest (which they are likely to perceive as a predation attempt), indicating that they are generally more cautious or anxious than non-solvers.

Why might 'being smart' not always be the best strategy?
EC: Being smart is costly. In humans, for example, the brain only accounts for 2% of an adult’s body weight, but it consumes about 20% of the resting metabolic rate [Clarke and L. Sokoloff 1999].

As resources are limited in nature, energy spent on the brain must be diverted from something else such as maximising body size and strength. Therefore although in some environments it will pay to be brainy, in others animals may benefit instead by investing resources in being good at competing or fleeing predators.

Whether being smart is favoured by selection is therefore likely to depend on the specific selective pressures acting in a given environment.  In a previous study we showed that problem solver great tits are poorer at competing for limited food resources than non-solvers, and in the current study we find that solvers may also be more timid. These correlations provide support for the idea that trade-offs may exist between problem-solving ability and other traits linked to fitness, and therefore that being smart may not always be the best strategy.

What further studies are needed to explore the link between 'smarts' and 'success' in great tits?
EC: Our paper provides an important first step to understanding how selection may act on individual variation in cognitive performance in animal populations. However, more work is needed to understand exactly how being a good problem solver helps animals do well in the wild: for example, are they better at finding novel food sources when most needed, or are they quicker generally at learning to cope with challenges in their environment?

Another useful area of research will be to further explore the costs of being smart. In our paper we show that solvers are more sensitive to disturbance at the nest than non-solvers, leading to high nest failure, but whether they also show a stronger response to natural predation attempts remains to be tested.

Finally, it will also be very interesting and informative to explore how different types of cognitive traits (such as learning ability) relate to fitness, and to test the prediction that the costs of being smart will lead to high cognitive performance only being favoured in environments that are especially cognitively demanding.

At ESO's Very Large Telescope (VLT) in Chile they are about to fit a new instrument that can record the light from 24 galaxies simultaneously.

KMOS has 24 robotic arms tipped with gold-plated mirrors that can be trained on a different galaxy – each arm has almost 200 facets making them rather like an insect's compound eye. Light from these mirrors is channelled into 3 spectrographs and 'multiplexed' – combined into a single signal.

The 3 spectrographs were designed, manufactured, and assembled at Oxford University before being shipped out to Chile via STFC's UK Astronomy Technology Centre in Edinburgh.

Working at infrared wavelengths, KMOS will probe a crucial time in the evolution of galaxies: around 10 billion years ago when star formation was at its height and the black holes believed to nestle in the centres of most galaxies were also highly active.

'Not only will KMOS accelerate the study of high redshift galaxies through the multiplex advantage, it will also provide a much more detailed view, allowing us to study gas flows and star forming regions in each individual galaxy,' Roger Davies, who led work at Oxford on the KMOS spectrographs, explains. 'We expect that these will reveal the connection between the evolution of the stars in galaxies and central black hole.'

The Oxford team are particularly interested in looking at galaxies in rich clusters: swarms of galaxies that occupy a compact volume and so live in a dense environment at a common distance.

In the nearby Universe these cosmic laboratories host large populations of structureless galaxies that appear to have completed almost all their star formation. 'KMOS will help us to identify the physical processes that give rise to this particular population of galaxies in clusters,' Roger tells me.

Over the last decade the spectrometers for KMOS were designed and constructed in Oxford University's Department of Physics. An experienced team of Ian Lewis, Matthias Tecza and Niranjan Thatte, as well as Davies, have established a strong track record for Oxford in instruments of this kind having built instruments for the the Mt Palomar 5m and the Japanese Subaru 8m telescope in recent years.

Building KMOS was a huge technical challenge: 'The whole interior of the instrument is cryogenic – cooled to 100 Kelvin [-173 Celsius] – so the spectrographs have to work at these extreme temperatures,' Ian Lewis tells me. The Oxford team worked closely with colleagues at the Rutherford Appleton Laboratory on the optical design of KMOS, whilst the Thin Film Facility gave it its golden glow – gold-plating all the mirrors for the device.

KMOS can detect emissions from gas at very early times in the history of the Universe that is normally invisible in images of the sky. The light from gas at high redshift can be concentrated in emission at a single wavelength, when an image is recorded over a broad range of wavelengths this light can be swamped and not detectable above the background glow. Because KMOS spreads the light out in wavelength over an area of sky, it can potentially detect the sharp emission lines from the most distant gas known, 'This could be one of the most exciting results from KMOS,' Roger adds.

The instrument is a collaboration of six institutions in Germany and the UK, including STFC's UK Astronomy Technology Centre, Durham University, Oxford University and RAL Space at STFC's Rutherford Appleton Laboratory.

Studying land-based birds is tough enough, but studying seabirds that spend much of their time over, on, or under water presents a new set of challenges.

In this week’s Journal of the Royal Society: Interface, a team led by Oxford University scientists describes how new technologies and techniques made it possible to follow an important British seabird, the Manx Shearwater.

I asked lead author Ben Dean of Oxford University’s Department of Zoology about the study and how the team’s findings might help in efforts to conserve shearwaters and other seabirds…

OxSciBlog: What are the challenges of studying shearwaters?
Ben Dean: Manx Shearwaters are elusive seabirds. They visit their breeding colonies only at night and nest underground in burrows where they rear single large chicks. The rest of the time they spend foraging at sea, often travelling hundreds of kilometres in search of food.

Studies at the colony have taught us much about their breeding and parental behaviour, while ship-based surveys have given us an understanding of the overall at-sea distribution of the species, yet we still know relatively little about patterns of behaviour at sea.

Understanding the at-sea behaviour of seabirds such as shearwaters is important because of their vulnerability to changes in the marine environment and their status as indicators of ocean health. But because of their elusive life-style and relatively small size, following individual birds from known colonies and recording detailed behavioural data is difficult.

OSB: What technologies did you use to investigate their behaviour?
BD: Advances in miniature data logging technology have revolutionised the remote observation of long-distance movements in seabirds. We deployed three types of miniature bio-logger simultaneously, each collecting different types of behavioural data:

Global Positioning System (GPS) loggers recorded the routes and movement speeds of foraging birds, saltwater immersion loggers recorded the proportion of time spent on and off the sea, and time-depth recorders logged each dive made in pursuit of prey.

Handling the increasingly complex datasets generated by these technologies is in itself challenging and so we employed a machine learning method to build a detailed picture of the at-sea behaviour and then applied what we had learnt to a large dataset in which we had tracked the movements of shearwaters from different colonies over three years.

OSB: How do your results add to what we already knew?
BD: First, we were able to show where and when shearwaters from different colonies engaged in three principal activities at sea: resting on the surface, commuting flight between colonies and foraging areas, and foraging behaviour. This type of information is of high value in conservation planning, particularly with respect to interactions between particular threats and those behaviours that increase risk: for example roosting and surface pollution, commuting flight and wind turbines, or foraging and fisheries.

Second we were able to reveal details of the foraging behaviour of this species, which primarily involves tortuous searching flights over relatively restricted search areas interspersed with frequent landings and take offs and diving in pursuit of prey.

Third we showed that birds from two different colonies in the Irish Sea foraged in local waters that were exclusive, but that birds from both colonies overlapped in one key area: the western Irish Sea and the Irish Sea Front.

Birds breeding at the colony furthest from the front spent more of their time at sea engaged in commuting flight and less time engaged in foraging activity than birds breeding close to the front. This suggests that birds breeding far from this important foraging area must work harder to locate prey, presumably at a greater cost to their own body condition.

OSB: What further research is needed to discover more about the lifestyle of Shearwaters/other seabirds?
BD: Further studies combining detailed data from multiple loggers will allow us to investigate how shearwaters respond to oceanographic features such as fronts, or prey distributions and to understand the kinds of decisions they make when searching for food.

Given that these birds cover such large distances during foraging trips, the analysis of GPS tracks to investigate the mechanisms of navigation and the learning of locations and routes is also likely to uncover interesting facets of seabird behaviour.

The future of seabird research almost certainly lies in multidisciplinary approaches that combine classical field biology with bio-logging, computational biology, molecular and chemical techniques. Such approaches will increasingly reveal ever more fascinating aspects of the elusive lifestyles of seabirds.

Meet Ossie: a friendly green popsicle who has already been fired through the LHC and frozen to absolute zero in a bid to explain cutting edge science.

In his latest adventure the star of the Oxford Sparks portal ends up getting a close encounter with a broken heart and finds out about the potentially dire consequences of one genetic mistake.

'Genetics has come such a long way, it really does impact on the way we look after patients already and will do so more and more,' said Hugh Watkins, the lead scientific advisor on this new animation.

'But it's the 'simple' end of the genetic spectrum, where a single genetic change causes an inherited condition that runs in a family, where we've made most headway so far. And the condition covered, hypertrophic cardiomyopathy, is one of the most common and important of these.'

Hugh says that, as part of explaining where the latest Oxford research has got to in investigating such conditions, he told 'some stories (one involving a forklift!) to illustrate the way it impacts on patients,' and that this tale made it into the finished animation.

He adds: 'I like the way that the animation and script make an inherently scary condition, and a serious science story, fun.'

Look hard enough, string theory says, and at a scale so small that atoms loom as large as entire continents do to us you would see that every particle in the universe is just the product of vibrating strings.

It's a powerful idea that could help to explain everything from black holes to hidden dimensions, and lead to a new understanding of gravity.

But string theory is also enigmatic and baffling, describing a realm that is, with current technology, too small for us to explore directly.

A new website, Why String Theory?, aims to tell the story of the theory's past, present, and (possible) future in a way that anyone can understand.

'We all instinctively want to explore the world around us. String theory gives us a chance to uncover the most fundamental laws of nature. So much of fundamental physics nowadays is completely inaccessible… We wanted to rectify this, conveying the excitement of contemporary research,' Edward Hughes, a Cambridge University undergraduate and member of the team behind the website, tells me.

'I'm still on the fence as to whether I think string theory is the right direction, but there are certainly elements of it that are very simple and appealing,' says team member Charlotte Mason, an Oxford University undergraduate. 'The idea that the myriad of particles in the universe could arise from different vibrational patterns of tiny strings is a very elegant explanation. Though the mathematics beyond that is often not so elegant!'

Joseph Conlon of Oxford University, another member of the team, explains that part of the theory's appeal lies in 'string miracles', these are 'calculations that look like they are going to fail and show that the theory is inconsistent, but then something comes in and suddenly saves the day. Once you see this happening several times you realise that the theory has a very deep structure and your understanding of it only scratches the surface.'

String theory is not the only approach that it is hoped might one day encompass the behaviour of everything from galaxies to sub-atomic particles, but it does appear to offer some tantalising insights. One of these concerns some of the universe's most mysterious objects: black holes.

'Objects in string theory called branes can be used to count the number of possible ways you can make a black hole,' Joseph tells me. 'For certain types of black holes this agrees with a famous calculation of Stephen Hawking of the entropy of the black hole.

'Entropy is a measure of how many ways there is of making something. Hawking used clever arguments to say what the answer must be. In string theory you can count the number of ways explicitly and find that it agrees with Hawking's answer.

'String theory can help solve problems with quantising gravity by treating particles as strings rather than points. This smears out interactions and makes infinite quantities finite.'

But, however powerful its insights, there is a problem: so far no one has been able to prove that those tiny vibrating strings the theory depends on actually exist. Joseph admits that they will be hard to find: it will, he thinks, take a major technological advance, a brilliant insight, or wonderful luck to turn up the right kind of evidence.

Yet string theory has a habit of turning up surprises, as Joseph says: 'Working on it is also good for humility, you are perennially aware that the theory is smarter than you.'