thinking but there is some good news from the north pole we'll hear more. mental illness which genes are linked to schizophrenia a large scale study aims to find out. and beavers have been called nature's engineers but not everyone likes what they built. welcome to tomorrow today the science show on d w. is this really ice it is under polarized light ice shimmers in a rainbow of colors. and this is where it comes from the arctic whether sea ice has been declining for decades. and international research group spent a year studying it to get a better understanding of climate change and its impact. think.

we'll take winter is a black void in 2 senses 1st it's dark thanks to months of poland nights in which the sun no longer rises over the horizon plus there's a huge data hole we know precious little about winter in the area around the north pole which plays a major role for our climate and is itself changing the ice has been receding for decades now what explains this climate change sure but how exactly does that affect this northern most part of the planet because if so how is the sea ice changing how does it grow in the winter and how does it melt in the summer. and hottest is a sea ice geophysicist in the alfred v. in the institute in gemini he sees the arctic winter as the key factor. that the ice forms in the winter and indoors through the summer. or. it has to consider. rable influence on the summer and therefore on the entire climate system

1st. but to really study during winter you need to be at one with the ice an international research team made that very commitment since last october the poor lash down research ship has been drifting across the arctic ocean trapped in the pack ice. it's the center of the largest arctic research expedition ever lasting one full year. when it's colder than minus 30 or even down to minus 60 with the wind chill factor it's very hard to work and also very dangerous you have to cover up your entire body. most christian hoss and his team use the winter months to investigate the sea ice on a quest for answers to the big question why is it shrinking. their work involved extracting ice cores measuring the temperature and movement of the ice and cutting

samples into thin slices their mission as such is not one of discovery but a data gathering to compile a detailed biography of the ice but they have made one major discovery during a dive by the trusty robot submarine. but of what it was something i'd been hoping and searching for what i didn't know was what it would actually look like. just below the ice in the sea water the robots came across glistening cloud like masses comprised of ultra thin plates of ice known as plate let ice. plate lead ice is very macroscopic you can see it there sheets of thin ice as big as your hand. they get stuck frozen onto the underside of sea ice and in various orientations. as the robot submarines. swims around in the

dark it's lamps reveal all these things glittering in the distance. going through as it gets closer you can see that there are ice crystals. it's a phenomenon already familiar from antarctica and one that the researches have now been able to observe for the 1st time in the arctic. platelet ice can only form when the sea water beneath the ice has a temperature colder than 0 degrees celsius this super cooling leads to the water freezing and forming plate tectonics as seen on the ropes and gauges that the research is lower in the countless cavities or cause emerge between the plate let's create what's called the poorest layer. it's a habitat not just for microorganisms and algae but also for zone as a kind of tiny crustaceans such as krill coppa pods and amphipods we saw ample pods

moving around the plate laid eyes looking for algae to eat and they are also protected there from bigger animals from fish in particular arctic cod that would happily eat them or humans with. a newly discovered layer of arctic ice and one more that needs more in-depth analysis while the expedition across the arctic ocean continues christian haas is now back on land together with untold terabytes of data now waiting to be deciphered but his team do have at least preliminary insights into the big question of how the ice in the arctic is changing but. it was very interesting to see that when we came onto the ice flow in october the ice was only 30 to 50 centimeters thick. and over the course of the winter over the following 5 or 6 months it grew to almost 2 metres and that miss that is it almost. drupal that's

a very important discovery. until now research is new only even the surface of the ice has been shrinking as seen by satellite suspiciously well during the summer over the last 4 decades that surfaces almost tom fitton size. satellites cannot measure however is the thickness of the ice. what we've now seen is that at the start of the season at the end of the summer. the ice was much thinner than it had been 30 years ago the last time we measured ice in the syberia an arctic. ocean artist. what surprised us is how thick the ice became. by the end of winter it was not much different from the way it had been back then. as we have established that changes are greatest during the summer not only in terms of the extent of the ice but also to its fitness and that the ice recovers relatively well in winter. and then the fact that the ice is so since by the end of the

summer actually helps to ensure that it recovers significantly in thickness jew in the winter i just don't know as for adults when the ice is thin and the ocean loses heat faster and more easily and that leads to the creation of more ice. as a consequence by the end of winter the ice is again about as thick as it was 30 years ago. but there's a lawmaking news to new surveys predict that the arctic ocean is likely to see ice free some a spike 2050. at the alfred vega institute's ice cold lab in a half and the temperature is held at a steady minus 25 degrees celsius the facility is home to various some poles from the arctic expedition such as these thin slices of ice cores which turned into crystals on deposit your rice light. we cut these thin slices of ice cores to see how the ice had grown whether the growth process was slow and under

calm conditions which would create these long colomba crystals. or if there had been strong waves in turbulence in the water. system then only these small round grainy crystals develop across time and record for christian house expects the arctic ocean to become more turbulent making it impossible for long column shaped ice crystals to form properly that will bring changes to the arctic ocean granular ice could then become more prevalent another insight into the workings of the arctic the prime cause the tiny crystals remind us that large structures are made up of small parts on the earth or the universe on the one hand and 2 atoms on the other everything is important and has a role to play a tiny and fascinating world that is a crucial element in the still mighty pack ice that covers the arctic.

what is right why i'm very glad i'm do you have a science question you've always wanted answered we're happy to help out send it in and if we answer it on the show you'll get a little surprise as a thank you come on just awesome. more stories from the world of science go to our website or find us on twitter d w underscore science. money mark must some that wants to know want our genes. genes are found in most of the cells in our body. a gene is made up of d.n.a. found in structures called chromosomes and the cell nucleus. one important thing genes do is provide instructions for building up all the various parts of our body. genes also underlie our body

processes and to a large degree they determine what we look like. the human genome that is the entire set of our genes has been sequenced. we have more than 20000 protein coding jeems. a lot of research is going into finding out what our genes actually do. for example are there specific ones that determine how long we live. a helper in that particular quest is the naked mole rat this remarkable rodent is long lived and remains fit and healthy into old age its genome is well understood. as to us one field of research is the role of genes in our ability to taste things and to find something yummy and others nest. it turns out that's not just a cultural matter but also a genetic one. a technology

called crisper it's genes it modifies the cells genome by removing or adding bits of d.n.a. . this enables it to turn genes on or off in plants and in animals including humans . society will have to think hard about the implications of science is growing ability to engineer our genes. just hearing voices. visual hallucinations. delusions. schizophrenia is a mental disorder associated with changes in perception thoughts mood and behavior it can be hereditary so what genes are associated with the disease. the psychiatric clinic at berlin's university hospital. a study here involves

healthy test subjects providing some life or samples containing their genetic material and stupid to suffer from schizophrenia. geneticists. is looking for genes that may play a role in the disease. a minor presume lesion of my personal hope is to shed light on to the darkness of psychiatric. knowledge so to speak. to. people who suffer from schizophrenia may hear voices and be paranoid. it's unclear what's really happening inside their brains which is why treatment options have hardly changed in decades. but schizophrenia is known to be highly heritable a factor that geneticists now want to unravel. there conducting large scale genome wide association studies with tens of thousands of test subjects including those in

berlin. each individual's genetic material is examined for components that may be different for each person called single nucleotide polymorphisms or snips. the schizophrenia patient snips are then compared with those of all the healthy test subjects using statistical calculations. certain snips are clearly more common among schizo phrenic looking at the genetic makeup in its entirety the especially common snips stand out like skyscrapers a comparison of $35000.00 schizo phrenic with $47000.00 healthy subjects revealed 108 snips associated with the disease. the researchers call the confusingly complex genetic landscape a manhattan plant due to its resemblance to new york's famous skyline. the snips identified the prominent skyscrapers constitute

a vital clue they point the way to the genes that may play a role in schizophrenia. and is also what we were a little bit afraid of that it's not just one gene that makes a person sick guns feel for sheet it's really many different genes that when combined. and create a person's individual risk says arkansas. and there are hundreds the researchers analyzed every single gene they've just discovered genes that influence the transmission of signals within the brain stefan hca presents the results at the european schizophrenia congress in berlin. i also want to show some other regions. among the hundreds of genes is one that is affected by the medicines currently being used it's good so for any a treatment a match that has researchers hoping for other positive results were decided owns

this so this shows us that one central gene can be enough to immensely improve treatment of others because it's just a question of finding it is not normal. this is crazy it's like taking a step on the moon but it's still a long way off because we know that developing medicines takes decades. and. a mammoth undertaking which is why hundreds of researchers have teamed up via the psychiatric genomics consortium including stefan. with the help of large scale genomic studies they're also researching other psychiatric disorders many of which now have a manhattan plant like the one for schizophrenia they provide a guide towards the relevant genes. but entirely different fields of application are also hidden within the genetic landscapes. the most hotly debated is the potential for polio to be used in diagnostics for instance or to predict the

risk of disease does that mean a person's genetic material could be a predictor. each individual's genetic material can be examined for d.n.a. sequence variations associated with the disease the number and nature of snips found can be used to calculate a personal policy. such as for schizophrenia. in some cases an individual's risk of succumbing to the disease can already be estimated but to pick up a pandora's box with problems. isn't sick. and you tell them risk values for a disease that person may never develop. and would have enormous consequences for the person themselves of course as well as their family their

friends their associates. says legal issues and it raises insurance issues. apart from that putting the likelihood of developing the disease into numbers is restricted to the genetic element only. a person lives and what happens in their life cannot be predicted environmental factors play a role sometimes a major one in the development of psychiatric illness. experts. risks are not suited to predicting risk or aiding in diagnosis but they can be useful. or it already does have a very large influence is in research. team divides the test subjects into groups according to the subjects. and then they observe how the group with the especially high schizophrenia scores develops the researchers are

a long way from totally understanding the complex genetics of psychiatric diseases but they are making progress. in a moment we'll be taking a look at me well but you votes we're pretty impressive small but mighty well not all that small we can reach a length of 135 centimeters and y. up to 36 kilos. plus our fur is unusually thick you few months have up to $600.00 hairs per square centimeter of skin we have up to $23000.00 top that. take other stuff of legends. we use them to build gigantic structures like this a dam 850 metres long so big it's visible from outer space no wonder you call us

busy. we might be rodents but we're also ecosystem engineers geniuses though not all humans agree. most people tend to think of beavers as a nuisance as pasts but it turns out that beavers very beneficial to the ecosystem . here in the river valley of southern germany water buffalo are helping keep these fields healthy organic farmer mathias license is bringing them in for the. oh come on sweetie come on. the water buffalo will spend the winter months at the family's farm. soviet state so. during the summer the water buffalo had some company here beavers. hot shot a wildlife biologist is often killed in when beavers looked like they might come into conflict with farmers or other local residents this past summer the beavers

built a dam along the edge of the meadow. the other country god has been working herd that's pretty fresh out there raising the dam for the winter. the obviously high for just a few yeah we're really glad to be there built this big dam along a pasture this year because as you see that allows the water to flow into the grazing areas this is a year old to deflect if you hear i didn't serve us a little bit too much then just our water buffalo need watering in wallowing holes to regulate their body temperature during the hot summer. only to be activated without the beavers activity here we'd have to either get water for the animals from outside or take them off the pasture did so with that. but not everyone is such a fan of the dams the beef is build. a little bit give him a bomb in the rates of return to see confluence when be busy build their dams are places that people are also using. this dam for example it's created this wet area

which can be used by other animals. and there's a path is no longer obsess about it so wet that anyone driving on it would get bogged down so the entire valley several hectares of land is no longer accessible for human use and he say that beavers set up shop because they like eating the corn from that field they also use the corn stalks to build their dam but that block the drainage and so now the areas under water this is what you tend to see when humans use land that is too close to water was. along this stretch of land adjacent to the east river the local villages aren't bothered by the dams it's a good spot to study the long term effects of beef or activity could cut salmon knows the area like the back of his house. decision here. we've been studying this habitat for 25 years so the winter is an especially good time to see what's been happening. often dumb the vegetation has receded and you can see the dam better and

move along here more easily without. the nearby university of applied sciences carries out a lot of research projects here the 1st signs of beaver activity were detected here in 1909 and researches have been monitoring the area ever since. just this used to be a relatively narrow stream with pastures to the right and left of that a small stream the landscape is totally changed in that the 1st choose forces that are less than 80 centimeters deep to build that dams the water behind the down that rises creating the beaver pond. sint or to keeps flowing into the bondage eventually bursts its banks those streams of water branch out eventually a complex ecosystem emerges with patches of standing water as well as small streams

some moving slowly others small quickly. we start to grow along the pond so much trees die off and a marshland emerges nearby this gives rise to a vibrant most say a very tough attacks. this year will go be firstly it's fascinating to see how such a small animal can shape and transform an area if you believe versus built a dam here that's more than. 120 meters long and several generations of them kept doing it and it's all in your chosen. news the small streams to circumvent the dam on to study carried out by the university of exeter showed that the dams actually improved the water quality. that's because the dams act as natural filters removing suspended solids phosphates and nitrogen from the water downstream from

a beaver dam the water contains about 70 percent fewer suspended solids 30 percent less nitrogen and 80 percent less phosphate on average than the water on the other side of the barrier. the sediment is deposited upstream of the dam where it's used by plants such as reeds which an average by the phosphate and nitrogen. the reed filled marshland the various will show ecosystems and the decaying would provide a rich habitat for many animals some quite uncommon situation you can really see how life has returned to the area here starting with the dragonflies before we only had a few dragon fly species but now the experts have found 30 different species of them here then there are the amphibian and bird species which are now flourishing. just how to really potency that. many long term studies

confirm that beavers boost the diversity of species in their habitats the busy creatures on pests atoll but valuable allies in the fight to preserve our rapidly dwindling biodiversity. that's all for this way kong tomorrow today nice that you could join us next time we'll have more exciting stories from the fields of science and technology until then good bye.

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