Becky Ripley and Emily Knight dig deep into the underground web of plant roots and mycorrhizal fungi networks. Here lies a 400 million year old market economy, founded on the trading of resources. Nutrients are traded for carbon. Carbon is traded for nutrients. And the exchange rate between the two is constantly in flux, to level supply with demand. This highly-evolved symbiosis between plant and fungi is crucial to the survival of over 80% of all terrestrial plants. And it also acts as a...

Becky Ripley and Emily Knight explore whether we can ever know what others know, and how we figure out if they're telling fibs. Beneath the surface of the ocean, darting around in the dappled sunlight of the reef, you can find some of nature's most prolific liars. The cephalopods. Squid, octopus and cuttlefish; filthy con artists, the lot of them. They communicate with each other, and with both predators and prey, using dazzling patterns of shifting colour and texture on the surface of their...

Becky Ripley and Emily Knight tackle a topic we love to fight about: parenting. How should we raise our kids? How much love is too much? Good parenting begins at home. And 'home', in this case, is a decomposing mouse corpse, rolled into a ball and buried 5 inches beneath the soil of the forest floor. Naturally. This is the home of one of nature's most diligent little parents, the black and orange Gravedigger, or Burying Beetle. The two parents team up to feed, nurture and care for their grubs...

Becky Ripley and Emily Knight explore the art and science of medicine: What makes you sick? What makes you well again? And how on earth do we (and animals) tell the difference? Deep in the rainforest of Sumatra, one clever orangutan called Rakus has pretty much got it figured out. Astonished researchers spotted him making and then applying a sophisticated plant-based medicinal paste to a painful wound. It was anti-bacterial, anti-fungal, and it numbed his pain, helping him to heal in record...

Becky Ripley and Emily Knight dive into the watery world of rainbowfish to confront the age-old myth that fish have bad memories. In actual fact, they are much more intelligent than we like to think, with an incredible capacity for learning and memory, as seen in almost all fish species. Their ability to remember complex things over a long period of time means they can build social relationships, navigate huge distances, and even form cultures, as knowledge is passed down over generations....

Becky Ripley and Emily Knight return in the series that turns to the natural world to try and make sense of what it means to be human. The new series is available from 29 July

Becky Ripley and Emily Knight tackle a serious question. One of supreme scientific importance: do animals get wasted? From drunk moose stuck in trees, to wasted wallabies asleep in opium fields, to dippy dolphins puffing on toxic pufferfish; stories abound about animals who seem to be using their free time to get sloshed. But do these stories, delightful as they are, stand up to scrutiny? In the natural world, when your survival relies on keeping your wits about you, what could be the...

Becky Ripley and Emily Knight find out what it takes to learn the language of your people, with the help of some extremely chatty little birds. The song of the zebra finch has been compared to a 90's dial-up modem running triple-speed, or an alien fax machine. But to a female zebra finch, it's a song of irresistible seduction. The males learn their song in a very similar way to the way we learn language, and it all starts with the babies. Through babbling, then copying, then innovating...

Becky Ripley and Emily Knight investigate physical fitness in the animal kingdom, and ask why animals never seem to have to go to the gym. Consider the Barnacle Goose, getting ready for one of the most phenomenal physical challenges of the animal world: the annual migration. They leave their sedentary summer life, floating about eating reeds, and take off to fly 2,700 miles. And what do they do to prepare for this incredible feat? Absolutely nothing. They just sit around, eating as much as...

Becky Ripley and Emily Knight dive into the underwater world of killer whales, where tight-knit family pods are led by the eldest post-reproductive matriarch, to better understand why we have a menopause. Matriarchal killer whales usually stop being able to reproduce in their thirties or forties, but continue to live for decades longer. This phenomenon of having a long post-reproductive life is known only to exist in 5 species: killer whales, narwhals, beluga whales, short-finned pilot...

Becky Ripley and Emily Knight look to the giggles and guffaws of the animal kingdom to ask where human laughter has come from. At least 65 species have been identified as making 'play vocalisations', a sort of animal version of laughter, according to a recent UCLA paper studying animals at play. Rats giggle in ultrasound, elephants have a play-specific trumpet, and kia parrots cackle from the treetops. These sounds are auditory cues that have come from breathing during play, and they signal...

Two adventurers delve deep into the myth, legend and reality of the mysterious creature that’s said to roam the Himalayas. This documentary series from BBC Radio 4 follows amateur yeti enthusiasts Andrew Benfield and Richard Horsey as they travel across the mountain range searching for evidence that the yeti might actually exist. Available on BBC Sounds now.

Rhythm is everywhere in the biological world. The rhythm of heartbeat, the rhythm of breathing, the rhythm of gait and walking. In fact, in 'The Descent of Man', Charles Darwin wrote that the perception of rhythm is "probably common to all animals and no doubt depends on the common physiological nature of their nervous system.” And yet, recent studies have shown that even our closest living relatives, the great apes, can't seem to keep a beat. Becky Ripley and Emily Knight investigate. Enter...

Becky Ripley and Emily Knight look to the freeze-thaw abilities of the North American wood frog to ask whether we can freeze ourselves in order to return to a future world... Early March is breeding season for the North American wood frog. They are frisky because they’ve just thawed out having spent the winter not just in hibernation, but frozen at -18°C. How do they do it, and still survive? And what can we learn from their frozen ways? Enter the growing field in medicine called...

You may think 'culture' is one of those peculiar things unique to humans, like dancing to pop music or yelling at the TV. But you'd be wrong. Animals may not flock to the Opera, but they absolutely do have 'culture'; habits; traditions; ways of doing things that are passed down from one generation to the next. Animal culture has been studied in fish, mammals and even insects, and one of the longest-running studies is on a bird you might have spotted flitting around your garden, the humble...

We've all seen the Attenborough documentaries, full of the hurrying and scurrying of life on earth, the drama constantly unfolding. The natural world is a BUSY place... Or is it? The surprising truth is, away from the cameras, most animals spend most of the time doing absolutely nothing at all. It's not just the sleepy sloths and the cat-napping cats, even the critters with reputations for being the most industrious animals on the planet have an astonishing amount of down-time. Peer into the...

Becky Ripley and Emily Knight ask whether giving legal rights to things like rivers and forests changes how we think about the world that lives around us. The Whanganui River, in New Zealand, is a legal person in the eyes of the law. It is legally defined as a living whole, from the mountains to the sea, and two local Maori tribe members speak on its behalf as its legal representatives. Other nations have had similar thinking: the Amazon rainforest in Columbia, one of the Great Lakes in the...

Why are some sounds more frightening than others? Are there evolutionary origins behind the things we find scary? And is there anything more blood-curdling than a full throated scream? Becky Ripley and Emily Knight tune in to the sounds that send the shivers down our spines, via a frightened Marmot in the Rocky Mountains of Colorado, and a brand new kind of musical instrument known as the 'apprehension engine'. Beware listeners, you may be in for a fright.... Featuring professor Daniel...

As our global society becomes ever more mobile, with people migrating across borders and making new homes among strangers, how do we figure out how to fit in? Trust is the glue that holds society together, but trust - as we all know - must be earned. Becky Ripley and Emily Knight take a trip to the African savanna, to see what a mob of dwarf mongooses can teach us about migration, integration, and making friends across cultural divides. Featuring behavioural biologist professor Andy...

Why do we want the things we want? What really drives us? And how in control of our instincts are we? All questions you might ask the humble cuckoo. This dastardly bird - a 'brood parasite' - famously leaves its eggs in another bird's nest and flies off, never to be seen again. The enormous chick hatches, kills all its nest-mates, then runs its adoptive parents ragged with round-the-clock feedings. But why on earth do the poor host-parents fall for the con? To find the answer, Becky Ripley...

Becky Ripley and Emily Knight get to grips with fatherhood in the animal kingdom by way of the largest land animal on earth, a fully grown bull elephant. Like the majority of mammals, male elephants aren't directly involved in raising the youngsters - that's left to the matriarchal herd composed of grandmothers, mothers and daughters. But you'd be wrong to think that means they don't have an influence. Via an extraordinary physiological phenomenon unique to elephants, known as 'musth',...

What is this thing we call "consciousness"? It feels like a non-physical thing that somehow exists as a separate entity to our physical body. We might think of it as being located up in our brain where our internal chatter is generated, but the 'mind' still somehow feels separate to the 'brain'. Then along comes an octopus to complicate the matter. Octopuses clearly have consciousness and high intelligence. But the last common ancestor between us and them is a flatworm that trawled the sea...

Sex is simple. Or so we're taught; animals can be male or female. But even the briefest glance at the animal kingdom tells us that this simply isn't true. Some creatures have only one sex; some have three; some have none at all. Some animals are two sexes at the same time; some flip flop between them when the time is right. When evolution came to solve the problem of procreation, she did it in a myriad of mind-blowing ways. When it comes to humans, it's even more complicated - we have this...

Becky Ripley and Emily Knight celebrate the intelligence of a brainless slime mould. As single-cell protists, with no brain and no nervous system, slime moulds do not 'think' in human terms, but they can calculate and navigate complex systems with incredible efficiency and objectivity. With some help from a few oat flakes, because slime mould loves oats. One species in particular, Physarum Polycephalum, has proven itself to outwit us time and time again, from solving complex urban transport...