ExpeRimental; Rosetta; MOOCs

The Hubble Constant The Hubble constant is the current expansion rate of the universe but it seems to have changed over time. Hiranya Peiris, Professor of Astrophysics from University College London and Adam Riess, Professor of Physics and Astronomy from Johns Hopkins University, are both using different methods to obtain a value for the Hubble constant. But there is a discrepancy in their values. It used to be that the error bars on the two values overlapped, and so cosmologists thought they would converge as the experiments got more precise. But instead, as the error bars have shrunk, the discrepancy is getting more serious, and something must be wrong. They chat to Adam about potential reasons for this difference in calculations and what it could mean for our cosmological model of the universe. Is new physics required to evolve the description of the age of the universe as we know it to be more accurate? A synthetic E. Coli genome Jason Chin and Colleagues at the Laboratory of Molecular Biology in Cambridge have published this week in the Journal Nature their latest work to completely synthesise a new genome of an E. coli bacteria. Not only was the genome designed and manufactured by human means, it was also recoded in a way not used by nature, involving some 18000 edits. In natural DNA, several different codes can do the same job. As Roland Pease reports, the new genome instead uses fewer of these duplicates, demonstrating all sorts of possibilities for future designs of synthetic cells.Von Humboldt Friedrich Wilhelm Heinrich Alexander von Humboldt was a celebrated Prussian geographer, naturalist and explorer. He influenced Darwin and was the first person to describe human-induced climate change, based on his observations from his travels. Yet he has slipped into relative obscurity, at least in the English-speaking world.Andrea Wulf is an acclaimed author who has previously written about Alexander von Humboldt and is now back with another book about the explorer: The Adventures of Alexander von Humboldt. It’s a graphic novel (illustrated by Lillian Melcher) that celebrates the 250th anniversary of Humboldt’s birth and depicts his adventures on his 5 year expedition through South America. Adam Rutherford chats to Andrea about her book, why she chose to make it a graphic novel and how Humboldt’s views on the environment can be interpreted today.Producer: Alex Mansfield

16 Touko 201934min

A damning House of Lords' report into the provision of forensic science in England and Wales makes for uncomfortable reading for some but is broadly welcomed by those in the field. Prof. Niamh Nic Daeid, one of many who gave evidence to the Science and Technology Committee, gives her reaction and suggests how a combination of unsatisfactory regulation, profit and austerity pressures in a uniquely commercialised sector, and some surprising gaps in the science knowledge base has lead to a sorry situation. Spring has sprung and it's probably not too late to get the tomato plants in, but should you water them little and often, or more but less often? Madeleine Finlay reports from Wisley, where The Royal Horticultural Society's Janet Manning has set up a new experiment this year to answer that question. Janet is the first Garden Water Scientist at the RHS, and hopes to demonstrate that giving plants less frequent, but more generous, bouts of hydration encourages deeper root growth, building in resilience for those periods when water is harder to come by whilst also allowing gardeners ultimately to use less.Do you have a fabella? Or maybe two fabellae? Michael Berthaume, "Anthroengineer" at Imperial College London tells us about a curiously under-studied bone that some people have in their knees. Present in certain primates and quadruped mammals, but thought to have disappeared from human anatomy, it seems to have made a bit of a comeback in certain populations around the world over the last century or so. Quite why, quite how, and quite what it's for, seems something of a mystery.

9 Touko 201928min

In 2018, the International Association of Athletics Federations (IAAF) introduced new eligibility regulations for female athletes with differences in sex development (DSDs). These regulations are based on the contention that women with high levels of endogenous testosterone and androgen sensitivity have a performance advantage over their peers. South African middle distance runner, Mokgadi Caster Semenya, who won two Olympic gold medals in 2012 and 2016, and Athletics South Africa, are contesting the legality of these new regulations. The basis of their objection, at the Court of Arbitration for Sport, is that there is a lack of scientific evidence showing that endogenous testosterone concentrations substantially enhance sports performance. Caster, who is DSD herself, has lost her case and Adam turns to expert in sport, exercise and genomics at Manchester Metropolitan University, Dr. Alun Williams to explain the implications.Less than a decade ago, an entirely new branch of the ancient human tree was discovered. These new hominins were named the Denisovans, after the Denisova cave in the Altai Mountains in Siberia where fragments of finger bone and teeth were discovered, and genetic sequencing of a finger bone revealed that they were a new hominin group, an extinct sister group to Neanderthals. This exciting find contained a tantalising puzzle. Traces of Denisovan DNA are found in modern-day population groups like Sherpas, Tibetans and some other neighbouring populations and this includes genetic variants which help them to survive at high altitudes where the oxygen levels are low. The original Denisovan cave is only around 700 metres, so why would such an adaptation be necessary at these altitudes? This week a new paper in Nature slots a big piece into the puzzle. Teams from the Institute of Tibetan Plateau Research and the Max Planck Institute for Evolutionary Biology have found another Denisovan fossil – this time a mandible, a lower jawbone, still containing teeth – from the vast Tibetan plateau in China. At 2.3 Km above sea level, it’s very high and the air is thin, and 160,000 years ago, which is when the fossil has been dated to, it would have been a very challenging place to live indeed. In fact this jawbone is the earliest known hominin fossil found on this enormous plateau. Adam calls in Professor Fred Spoor, from the Centre for Human Evolution Research at the Natural History Museum in London, to examine the facts and to see if we can work out how far and wide these hominins travelled.Producer: Fiona Roberts

2 Touko 201927min

Patients who suffer neurological impairments preventing them from speaking potentially face a severely limited existence. Being able to express yourself in real time is a large part of our identity. In the journal Nature this week, scientists from the University of California, San Francisco, report a new technique for synthesising speech based on measurements of neural signals taken from the brain. Author Dr Gopala Anumanchipalli tells Adam about how this proof of principle could one day form the basis for a speech prosthesis for patients who have lost the ability to converse. Around the world this weekend (April 26th-29th 2019) people are being encouraged to participate in the City Nature Challenge, a global effort to catalogue urban wildlife using a free mobile app. Reporter Geoff Marsh travelled to the California Academy of Sciences, home of the initiative, to meet those behind it and how we might all take part.The third act in our drama is a chat with journalist and writer Will Storr about his new book - the Science of Storytelling - which explores the structure of stories with relation to our evolution and brain structure. Primeval instincts of expectation, subversion and causation intertwine with camp-fire sagas from the beginning of conversation. What can this science of storytelling contribute to the art of telling stories about science? A ripping yarn indeed.Producer: Alex Mansfield

25 Huhti 201928min

The horror of the blazing Notre-Dame cathedral in Paris has been slightly quenched by the fact that so much of the French landmark has been saved. But what was it about the structure of the roof, with some the beams dating from the 13th century, that meant it burned like a well-stacked bonfire? Guillermo Rein is Professor of Fire Science at Imperial College London , and he explains to Adam Rutherford how wood burns and how it was the intricate mixture of large and small beams, and very poor fire protection measures that made the iconic roof, so vulnerable.An experiment to see whether isolated dead pig brains could be preserved at the cellular level in order to study post mortem brains, had a surprising outcome. The BrainEx technology of perfusing the brains with chemicals that should have just halted the rapid degradation of cellular structure in the brain, that occurs soon after death, actually caused them to start firing neurons, reacting to drugs and generally behaving as if they were alive. Although, it has to be stressed, there was no whole-brain connectivity or consciousness achieved, it does raise ethical questions about death, if this method was to be developed for use in humans. Bioethicist at Kings College London, Silvia Camporesi explores the facts that reveal that death is a process rather than a single event and what this might mean for patients that are diagnosed as brain dead.Where is the Martian methane? This is the question Mannish Patel at the Open University has been left pondering after the ExoMars Trace Gas Orbiter came up empty handed in detecting the gas on Mars. Methane could be a signature of past of present life on the Red Planet, it's been measured by NASA's Curiosity rover and by telescopes on Earth, but the far more sensitive and specialised TGO has so far failed to detect the gas. It could be because methane levels in the thin Martian atmosphere is a seasonal event, we'll just have to ait for an entire Martian year of surveys to be able to solve this mystery.Our faces are incredibly important in our lives, we feed through them, they are the conduit for our sensory interaction with the universe, via smell, hearing and vision; we speak, and we convey the subtlest emotions with a raised eyebrow, a wry smile, a clenched jaw or eyes wide open. It is the central importance of these features that has meant we’ve been intensively studying the evolution of the face for decades, to work out why we look the way we do, and how much of our looks reflects adaptations that enhanced our survival, and how much is just down to quirks of evolution. Anatomist, Paul O’Higgins from York University is interested in how all that has influenced our faces. Producer: Fiona Roberts

18 Huhti 201933min

"We have now seen the unseeable" according to scientists who are part of the Event Horizon Telescope group. The international team has released a picture of the first black hole. Data gathered from an array of over 8 radio telescopes has been crunched to create a picture of the super-hot plasma surrounding the black hole M87. It shows extremely excited photons on the brink of being swallowed up by the supermassive black hole, 500 million trillion km away. Marnie Chesterton, asks UCL cosmologist Andrew Pontzen what the glowing doughnut-shaped image can tell us about the laws of gravity and relativity.A new species of hominin has been discovered in caves at the northernmost tip of the Philippines, on the island of Luzon. The discoverers have called this creature Homo luzonensis, and it's thought to be 50,000 years or older. The teeth, hand and foot bones suggest it could have been a mixture of early modern humans - Homo sapiens- and older ancestors like the Australopithecines. Cambridge University's Leverhulme Professor of Human Evolution, Robert Foley suggests some caution with calling this a new species, and explains how populations of hominins isolated on islands could evolve to be different by a mechanism called genetic drift.The world is facing an antimicrobial crisis. The global fight against infections is looking worrying as more and more strains of bacteria emerge which are resistant to our stocks of antibiotics. Marnie visits to Tblisi, in Georgia to meet scientists who are looking at a different way to fight infections, collecting and using the microscopic phage viruses which infect the bacteria which infect us. Another way to try and beat antibiotic resistance was the focus for Susan Rosenberg at the Baylor College of Medicine in Houston Texas, when she thought it might be clever to try and stop microbes evolving resistance to antibiotics . She discovered that when microbial cells are stressed, a number of them actually start to mutate at a greater rate. This means they stand a greater chance of mutating into a form that has some resistance to our drugs. But by learning about the finer details of this mechanism, and finding a drug that can halt it. She and her team hope to skew the evolutionary arms race between microbes and antibiotics and our immune systems in our favour.Producer: Fiona Roberts

11 Huhti 201938min

About 66 million years ago an asteroid at least 6 miles wide crashed into the Earth, in the shallow sea that is now the Yucatan Peninsular in Mexico. It gouged the Chicxulub crater 18 miles deep; threw 25 trillion tonnes of debris into the atmosphere, much of which was hotter than the Sun, created huge seismic waves and massive tsunamis churning the Gulf of Mexico, tearing up coastlines and peeling up 100’s of metres of rock. 75% of the Earth’s forest burned. Debris was thrown out across the Solar System and North America was showered by a fan of glassy molten rock droplets. This geological event marked the end of the Cretaceous period and the start of the Palaeogene. Most people accept that this massive event caused the last great extinction, the end of the dinosaurs and a period of intense cold. Many fossil finds back this theory up. But very little fossil evidence showing the impact of the actual event has been found. Until now. Hundreds of miles from Chicxulub in a fossil site called Tanis, in North Dakota, part of the vast Hell Creek formation, is a fossil find that depicts the turmoil 10's of minutes after the asteroid hit. Marine and freshwater fish are found tangled together with these glassy droplets crammed in their gills, Charred trees are mixed up with hundreds of mangled animal bones, amber perfectly preserving drops of what was molten Earth. It's got palaeontologists including Professor Phil Manning at Manchester University very excited.The gravitational wave detectors LIGO and VIRGO have been recently upgraded and made more sensitive to the miniscule signals that denote ripples in gravity - gravitational waves. Professor Sheila Rowan of the University of Glasgow explains to Gareth Mitchell that she hopes that with this third run of the detectors, they will be finding not just one or two signals that provide evidence of massive events in our universe, but hundreds, maybe even thousands.In the quest to understand how corals are affected by rising sea temperatures we need to understand the symbiotic relationship they have with dinoflagellates, the single-celled algae that live in, and use photosynthesis to make food for the coral. When coral gets too hot and undergoes 'bleaching', this is the algae leaving the coral. Yixian Zheng at the Carnegie Institution of Washington takes Roland Pease on a tour of her coral tanks and explains that she's hunting for a model coral organism to study this process at the genetic and molecular level.A crime has been committed in the studio. Gareth's tea has been drunk and his biscuits have been nibbled. Luckily evidence was left at the scene of the crime - a shoeprint with distinctive wear patterns. One quick phone call and the director of the Leverhulme Research Centre for Forensic Science at the University of Dundee, Professor Niamh Nic Daeid is on the case. She's asking the public to help build up a database of footwear prints. The project is the largest ever study into the variation in footwear marks made by the same shoes across different surfaces and activities so that the variation observed can be used to explore links between the shoe and the mark it makes. In order to do this, she's asking thousands of individuals to take part in a large-scale citizen science project by taking pictures of their footwear and the marks they make. This will help the Dundee team build a substantial database for use in their research to aid the scientific validation of footwear marks as evidence for use in the criminal justice system.Producer (and biscuit thief) - Fiona Roberts

4 Huhti 201939min

One of the longest running insect pollinator surveys in the world, shows that a few generalist pollinators are on the increase, whereas specialist insects are declining. Using data collected by volunteers across Great Britain to map the spatial loss of pollinator insect species, the study by the CEH (Centre for Ecology and Hydrology) measured 353 wild bee and hoverfly species across the country. The results showed that on average, each 1km2 survey patch lost an average of 11 species from 1980-2013. CEH's Professor Helen Roy and Dr Claire Carvell explain to Marnie Chesterton how volunteers can take part in the next survey.Want to know where a whale has been? Just ask the barnacles on its head! Barnacles hitchhike on whales, and they’ve been doing this for millions of years. When barnacles grow they add to their carbonate shells using compounds from their surroundings. As the whales migrate, the barnacles take up compounds from the different oceanic locations. A bit like filling in a travel diary, or collecting passport stamps. If you can decipher the chemical code laid down in the barnacle shells, you can work out where the whale has been on its oceanic migrations. This is what researcher Larry Taylor, at University of California Berkeley, has been doing and he says that the information can even be found in fossilised whales (and barnacles.)The patterns signals in our brain make when we are falling asleep are quite hard to study. But thanks to a few people who manage to fall asleep in an FMRi scanner, we now know there are multiple stages of sleep. Professor Morton Kringlebach, a professor of neuroscience at the University of Oxford likens the pattern of brain activity, as it enters the various sleep stages, to the choreography of a dance. His friend, Dr. Milton Mermikides at the University of Surrey, goes one further. As a composer and academic expert in jazz, he thought the pattern of brain activity was like chord changes in jazz music. So he put the sleepy brain to music. Marnie listens to the soporific tones and asks if people with disordered sleep, such as insomnia or restless leg syndrome would make different music?Producer: Fiona Roberts

28 Maalis 201927min