Physical World

Sloths are the slowest mammals on earth. They can hardly see. They live in rainforests among jaguars, pumas, and countless other predators. Yet they survive. And they do it by being so incredibly slow, and living a life covered in algae. In this episode, we hang with a sloth in the jungle of Costa Rica as he spends a month digesting one single leaf, and we see the symbiosis and collaboration that surrounds him.

Dogs are a familiar and comforting part of many of our lives. In this episode, we take a walk with a pet xoloitzcuintli, or Mexican hairless dog, as he greets his blocks by smell. Along the way, we learn the backstory of squirrels in U.S. cities and observe the very smart and clean neighborhood raccoon.

Elephants are the largest land animals in the world. They are also intensely social and have advanced long-term memories. In this episode, a parade of Asian elephants makes its way through the Sri Lankan forest to a lake for drinks and mud baths, stopping periodically for group naps. The female leading the parade uses infrasonic rumbles—inaudible to humans, but traveling as far as two miles along the surface of the Earth as seismic waves—to invite friends and family around the forest to join her at the reservoir.

Dung beetles might sound dirty, but the ancient Egyptians believed their god took the form of a dung beetle to roll the morning sun across the sky every day. In this episode, we roll with dung beetles around the world as they push their precious dung—often in balls many times larger than they are—over Florida pastures, Armenian highlands, and the vast South African savanna.

In 2014, after losing several friends and relatives to cancer, an unassuming insurance underwriter in Hoosick Falls, New York, began to suspect that the local water supply was polluted. When he tested his tap water, he discovered dangerous levels of forever chemicals. This set off a chain of events that led to 100 million Americans learning their drinking water was tainted. Although the discovery came as a shock to most, the U.S. government and the manufacturers of these toxic chemicals had known about their hazards for decades.

Humpback whales are among the most intelligent animals on Earth. Some scientists believe they might even surpass humans in self-awareness, empathy, and communication skills. In this episode, we swim with a whale as he teams up with other humpbacks to use bubbles to catch fish, rescues a sea lion, and puts his own spin on melodies sung by whales across the Pacific Ocean. This is the world in its natural state, defined by seasons, routines, and cycles. By the time this whale is ready to close one eye and go to sleep, you will be too.

Brown bears lead deeply cyclical lives. They need to gain sometimes hundreds of pounds during the warmer months to prepare for winter hibernation, a lifestyle that brings them into frequent contact with many other species’ cycles. In this episode, we meander through the Alaska peninsula with a bear and her cubs as she teaches them to hunt salmon at the falls, dig for clams along the coastal mudflats, and use the regional rubbing tree.

Platypuses are mammals unlike any other on earth. They lay eggs, ooze milk through their skin, and can sense electricity. In this episode, we travel with a platypus as he moves through his nightly routine on the island of Tasmania. He uses electroreceptors to hunt underwater and does a synchronized swimming courtship ritual with his mate, who then digs a burrow 40 feet deep into the riverbank to nest.

The sun sinks over the Rio Grande, the mountains around it glow orange, and the world slows down. The Mexican free-tailed bats inside the Jornada Cave are just starting to stretch and murmur. In this episode, we visit the nursery where all the baby bats stay together, and we accompany a new mother as she journeys into the sky with the rest of her crew for a night of hunting bugs via echolocation.

Fennec foxes’ ears can be up to half as long as their bodies. They use them to track movement across the Sahara Desert, including under the sand. In this episode, we follow a fox as he meanders home to his family through the sand dunes as they slowly shift with the wind.

Alexander von Humboldt (1769-1859) was an intrepid explorer and the most famous scientist of his age. His restless life was packed with adventure and discovery, whether climbing the highest volcanoes in the world or racing through anthrax-infested Siberia. He came up with a radical vision of nature, that it was a complex and interconnected global force and did not exist for man's use alone. Ironically, his ideas have become so accepted and widespread that he has been nearly forgotten.

Crows have long been the subject of folklore, likely because they’re strikingly similar to humans, leading lives rich in personality, intelligence, and relationships. In this episode, we fly the streets of Seattle with a crow as she grooms her mate, delivers what appears to be a gift, and finally commutes miles away from her territory to gather and chat with thousands of other crows before it’s time to roost for the night.

It can come in waves - like tidal waves. It changes societies. It disrupts life. It ends lives. As far back as 3000 B.C.E. (the Bronze Age), plagues have stricken mankind. COVID-19 is just the latest example, but history shows that life continues. It shows that knowledge and social cooperation can save lives. Viruses are neither alive nor dead and are the closest thing we have to zombies. Their only known function is to replicate themselves, which can have devastating consequences on their hosts.

In the tradition of Jared Diamond and Jacques Barzun, prize-winning historian Anthony Pagden presents a sweeping history of the long struggle between East and West, from the Greeks to the present day.

The relationship between East and West has always been one of turmoil. In this historical tour de force, a renowned historian leads us from the world of classical antiquity, through the Dark Ages, to the Crusades, Europe's resurgence, and the dominance of the Ottoman Empire, which almost shattered Europe entirely. Pagden travels from Napoleon in Egypt to Europe's carving up of the finally moribund Ottomans - creating the modern Middle East along the way - and on to the present struggles in Iraq.

In Four Lost Cities, acclaimed science journalist Annalee Newitz takes listeners on an entertaining and mind-bending adventure into the deep history of urban life. Investigating across the centuries and around the world, Newitz explores the rise and fall of four ancient cities, each the center of a sophisticated civilization: the Neolithic site of Çatalhöyük in Central Turkey, the Roman vacation town of Pompeii in Italy, the medieval megacity of Angkor in Cambodia, and the indigenous metropolis Cahokia, which stood beside the Mississippi River where East St. Louis is today.

The Emperor of All Maladies reveals the many faces of an iconic, shape-shifting disease that is the defining plague of our generation. The story of cancer is a story of human ingenuity, resilience, and perseverance but also of hubris, arrogance, paternalism, and misperception, all leveraged against a disease that, just three decades ago, was thought to be easily vanquished in an all-out "war against cancer".

Mr. Griffin marshals the evidence that cancer is a deficiency disease like scurvy or pellagra aggravated by the lack of an essential food compound in modem mans diet. That substance is vitamin B17. In its purified form developed for cancer therapy, it is known as Laetrile. Why has orthodox medicine waged war against this non-drug approach? The author contends that the answer is to be found, not in science, but in politics, and is based upon the hidden economic and power agenda of those who dominate the medical establishment.

It comes as no surprise that, as a kid, Jeopardy! legend Ken Jennings slept with a bulky Hammond world atlas by his pillow every night. Maphead recounts his lifelong love affair with geography and explores why maps have always been so fascinating to him and to fellow enthusiasts everywhere.

For American women today, working out is as accepted as it is expected, fueling a multibillion-dollar fitness industrial complex. But it wasn’t always this way. For much of the 20th century, sweating was considered unladylike and girls grew up believing physical exertion would cause their uterus to literally fall out. It was only in the '60s that, thanks to a few forward-thinking fitness pioneers, women began to move en masse.

Ross Donaldson is one the few who have ventured into dark territory of a country ravaged by war to study one of the world's most deadly diseases. As an untried medical student studying the intersection of global health and communicable disease, Donaldson soon found himself in dangerous Sierra Leone, on the border of war-struck Liberia, where he struggled to control the spread of Lassa Fever. The words, "you know Lassa can kill you, don't you?" haunted him each day. He'ss forced to make life-and-death decisions alone as a never-ending onslaught of contagious patients flood the hospital.