Discovery

From the plumbing of ancient Rome, to lead acid batteries, paint, petrol and a dangerous legacy, the metal lead has seen a myriad of uses and abuses over thousands of years. In bullets, and poisons it has killed us both quickly and slowly, and yet its malleability, low melting point and resistance to corrosion make it a fantastic material for all kinds of containers and water proofing. And it is key to one of the most commonly used, and ignored, devices on the planet, the car battery.

However it's only recently that the serious impact of lead poisoning on the development of children's brains has come to light.

Photo: BBC Copyright

Zoologist and founder of the Sloth Appreciation Society, Lucy Cooke, unleashes her inner sloth to discover why being lazy could actually be the ultimate evolutionary strategy.

The explorers of the New World described sloths as ‘the lowest form of existence’, but sloths are actually some of the most enduring of all tropical mammals. They make up one third of the mammalian biomass in rainforests and have survived some 64 million years - outliving far flashier animals like sabre tooth tigers.

The secret to the sloth’s success is their slothful nature and their suite of energy-saving adaptations. In fact slothfulness is such a successful strategy, that there are examples all over the animal kingdom, including, surprisingly, worker ants. Recent studies in humans have shown the many health benefits of adopting a slower pace of life. Sleep itself is universal amongst the animal kingdom. All animals do it, but why remains a mystery. What is clear though, is that unleashing your inner couch potato is no bad thing, be you sloth or human.

Lucy discovers the genius behind the sloths laid back attitude and fights the corner for laziness.

Producer: Alexandra Feachem

Picture: A young two-toed sloth sits in a bucket, September 2017. Credit: Klaus-Dietmar Gabbert / AFP / Getty Images

Does knowing that someone is inflicting pain on you deliberately make the pain worse? Professor Irene Tracey meets survivors of torture and examines the dark side of pain.

Producer: Geraldine Fitzgerald

(Photo: A woman mourns during the funeral procession of Abdulrassul Hujairi. Credit: Joseph Eid/AFP)

What if your brain could naturally control pain? Professor Irene Tracey and her colleagues are trying to unlock the natural mechanisms in the brain that limit the amount of pain we feel.

We hear about how children learning judo are taught special techniques and from ex-marine Chris Shirley who ran a marathon carrying a 45kg rucksack and could ignore the pain of the blisters and torn shoulder muscles.

Picture: The statue of the Virgin Mary, Credit: Francisco Leong/AFP/Getty Images

Producer Geraldine Fitzgerald

Scientists reveal why we feel pain and the consequences of life without pain. One way to understand the experience of pain is to look at unusual situations which give clues to our everyday agony.

Phantom limb pain was described in ancient times but only after WWI did it gain acceptance in modern medicine. For those living with it, it can be a painful reminder of a lost limb. New studies are now unravelling why the brain generates this often unpleasant experience and how the messages can be used positively.

Its only since the 1980s that doctors agreed that babies are able to feel pain but we still don’t know how the developing brain processes information and how premature babies can be protected from the many invasive tests they have to go through. New research aims to provide appropriate pain relief that could have long term consequences.

Picture: Nerve cells, computer artwork, Credit: Science Photo Library

Mystery still surrounds the experience of pain. It is highly subjective but why do some people feel more pain than others and why does the brain appear to switch off under anaesthesia so we are unaware of the surgeon’s scalpel? Professor Irene Tracey uses brain scanners to ask if we can actually see pain in the brain. On air we hear for the first time the results of the latest research into diabetes and nerve pain. Promising new techniques means scientists are able to see regions in the brain which effectively turn up the pain in some people and not others.

Anaesthetics prevent pain during surgery but how the brain disengages is only just beginning to be understood, which could in the future lead to personalised doses of anaesthetics leading to faster recovery times.

Picture: Graphic of neurons firing in the of the neural network within the Brain, Credit: Science Photo Library

In Bristol in 1799, a young man started to experiment with newly discovered gases, looking for a cure for tuberculosis. Humphry Davy, aged 20, nearly killed himself inhaling carbon monoxide. Nitrous oxide was next. It was highly pleasurable, ‘particularly in the chest and extremities’ and he began to dance around his laboratory ‘like a madman’, before passing out. By day, he gave the gas to patients, carefully noting their reactions. In the evenings, he invited his friends over to have a laugh (with assistants on standby to revive them with oxygen, as needed).

Picture: Humphry Davy and Anaesthesia, Credit: Science Photo Library

Philip Ball reveals the dramatic tale of Lise Meitner, the humanitarian physicist of Jewish descent, who unlocked the science of the atom bomb after a terrifying escape from Hitler's Germany. One of the most brilliant nuclear scientists working in Germany her flight from terror cost Hitler’s regime dearly.

In the early 20th Century it was barely possible for women to work in science at all and yet Einstein once called Meitner Germany’s own Marie Curie. It was Meitner’s insight that began the nuclear age and her story remains ever relevant, as the threat of nuclear conflict lies once again over the world.

Philip Ball talks to historian Dr Patricia Fara about Lise Meitner and her research and to Patricia Lewis of the International Campaign to Abolish Nuclear Weapons or ICAN, based in Geneva, which this year was awarded the Nobel Peace prize for its work in trying to reverse nuclear proliferation, about Meitner’s legacy today.

Picture: Lise Meitner, Credit: Central Press/Getty Images

Roland Pease tells the story of how fifty years ago geologists finally became convinced that the earth’s crust is made up of shifting plates. The idea of mobile continents, continental drift, had been talked about, for example because it looked like Africa and South America had once been joined, and were now separated by the Atlantic. But given the solidity of rocks and the vastness of continents, that idea made no sense. Until plate tectonics, as it became known, gave it a scientific basis and rebuilt it into a mechanism that explained earthquakes, mountain belts, chains of volcanic islands and many other geological phenomena. Roland Pease talks to many of the key researchers in the story, now in their 70s and 80s, and finds out how their work transformed our understanding of the earth.

Picture: Tectonic plates of planet earth - map with names of major and minor plates, Credit: PeterHermesFurian

Presenter: Roland Pease

Maria Merian was born in 1647. At the time of her birth, Shakespeare had been dead for 30 years; Galileo had only just stood trial for arguing that the Earth moved around the Sun. And yet, here in Germany, was a child who would become an important but oft-forgotten figure of science.

Aged 13, she mapped out metamorphosis, catching caterpillars from her garden and painting them in exquisite detail. At that point, most believed that caterpillars spontaneously generated from cabbages and maggots materialised from rotten meat. She later voyaged to Suriname in South America to pursue pupae further, discovering not just new species but also the conditions needed for their survival.

Some call her the first field ecologist; others admire her for her eloquent brushwork. However, her studies will help today’s biologists plot which insects lived where. These data are invaluable because this could help scientists predict what species will survive climate change.

Naomi Alderman discusses the life and legacy of Maria Merian with biologist and historian Kay Etheridge from Gettysburg College, Pennsylvania and biologist Kathy Willis from Kew Gardens.

Picture: Belly-ache bush (Jatropha gossypifolia) with metamorphosis of a giant sphinx moth (Cocytius antaeus), created by Maria Sibylla Merian and Joseph Mulder, Credit: GRI Digital Collections

Producer: Graihagh Jackson