TEACHERS: Try our Lessons free — get a 30 Day Premium Trial
As plants and animals reproduce over time, they are able to change and adapt to ensure or improve their chances of survival. The evolutionary goal of reproduction is paired with the concept of natural selection and survival of the fittest to determine who will reproduce. From colorful plumage to size, different species use different strategies to ensure reproduction and mate selection. The sand tiger shark has a unique strategy to ensure successful reproduction - and it depends on the timing of mating. Listen to learn more about the ultimate sibling rivalry while in the womb.
The increasing acidity of the oceans could eventually affect your dinner plate. There is a decrease in the number of juvenile oysters known as "seed" due to the increase of CO2 in the ocean. Listen to learn how workers are dealing with the issues and how it affects the seafood we eat.
Wolverines are fierce predators and scavengers that live in the remote forests near the Arctic Circle. As these solitary animals need at least 500 square kilometers of space each and can travel vast distances each day, they are very difficult to spot in the wild. Wolverines play an important role in the ecosystem as they scavenge the carrion left behind by other predators. Listen to hear more about this elusive mammal, including why people walking through the forest shouldn’t worry about being attacked by one.
The apples we are used to seeing in the supermarket are the same basic size and shape and they have familiar flavor profiles. But there are more apple varieties than you might imagine. There's a whole world of biodiversity in apples, but these apples don’t make it to the supermarket. Listen to learn more about America’s history with apples and the apple Renaissance taking place today!
To lower dependency on fossil fuels, some Americans have installed solar panels on their homes to produce their own clean energy. This decision involves a cost-benefit analysis of cost value and environmental impact. In some regions this cost-benefit ratio has been upset by fracking, and the cheap natural gas that it produces. How does supply and demand impact the cost of energy? How does the cost of energy impact people seeking alternatives such as solar energy? Listen to learn how one family has dealt is dealing with this shifting energy landscape.
Tsunamis are created by tectonic plates thrusting against each other and then lifting the sea floor and dropping it down, which creates a giant wave. A 2010 earthquake in Chile was caused by a shift in the seafloor. This same shift set off tsunami detection buoys and left scientists waiting for the tsunami to hit. But it ended up being small. Listen to learn more about this quake and how tsunamis are created.
When people started using large nets to capture tuna in the 1960s, many spotted dolphins were killed because they were found living with tuna. Scientists responded by sending “observers” on tuna boats to keep track of the number of dolphins killed. Listen to hear from a scientist who is studying the spotted and spinner dolphins to try to learn how to preserve dolphin populations.
Scientists are creating bacteria batteries by using wastewater to generate electricity. The microbes from sewage can be harnessed to develop microbial fuel cells. The process could provide ways to provide energy in remote places for very little money. Listen to learn how scientists are developing this energy and what they are learning from it.
One of the biggest earthquakes ever recorded struck recently, with minimal damage, no tsunami and it barely made the news. That’s because there are two kinds of earthquakes. This earthquake happened when two tectonic plates moved past each other horizontally, while more damaging earthquakes are caused when one plate slips beneath another. This radio story explains the two types of earthquakes and how they are gradually redefining the boundaries of the tectonic plates.
A new threat to human health, a disease called COVID-19, is spreading rapidly around the globe. The cause of COVID-19 is a coronavirus, named for the crown-like spikes on the surface of the virus particles. In this audio story, an infectious disease doctor describes COVID-19 and its symptoms, compares the novel (or new) coronavirus to the better-known coronavirus that causes the common cold, and explains why being novel helps the virus to spread. Listen to learn what scientists want people to do in order to slow the spread of the novel coronavirus and protect the health of individuals, families, and communities.
Global warming is expected to increase summer temperatures making cities even hotter. As concrete and asphalt within cities retain heat, it can increase health risks. The sun mixes with city pollution to create ozone that can irritate people's lungs, especially if they have breathing problems such as asthma. Listen to learn how public health officials are trying to help those living in the hottest areas.
Game wardens in California are now using DNA fingerprinting analysis to help protect illegal poaching of wildlife. There are many species, from large game to shellfish, which are being illegally caught or killed for food. Since there are so few game wardens to patrol the state, they are relying on forensic evidence to help track poachers. Listen to learn about the latest in DNA fingerprinting technology.
Alaska is home to 54 active volcanoes. Scientists, called volcanologists, watch and study these volcanoes to try and predict when they are going to erupt and so they can give warnings to the nearby communities. In 2008, Mount Redoubt, one of Alaska’s most famous volcanoes that is known to be active and dangerous, began to show signs of erupting. Listen as a volcanologist explains how taking a closer look at what goes on deep down below the surface of a volcano like Mount Redoubt can reveal warning signs that indicate a possible eruption.
As nations look for clean energy alternatives many are turning to wind and solar, but Indonesia is turning to its volcanoes. Indonesia has 130 active volcanoes. These volcanoes generate geothermal heat that is releases through vents and hot springs throughout the country. Power companies are learning to harness and redirect this heated steam into power plants in order to generate electricity. Indonesia’s geothermal energy potential is huge, but start up costs and oil subsidies might prevent this burgeoning clean energy from taking off.
A whale inhales and exhales air through the blowhole at the top of its head. The plume that rises when the whale exhales is made up of blow, a scientific term for whale snot. Whale snot can reveal important information about whale stress, but collecting the snot can be challenging. Listen to hear a scientist describe how she collects whale snot and what it can tell us about how whales are coping with the effects of climate change.
It's easy for some people to imagine what it's like to be a doctor, lawyer, or teacher. However, the day-to-day life of a shellfish and wetland ecologist can be a little more difficult to understand. Discover what an ecologist does by hearing from Danielle Kreeger, the science director for a group that works to protect and improve the Delaware River and Bay. Listen to hear more about her career as an ecologist.
What is electricity? How does it work? Where does it come from? Everyone has heard of electricity, but most people don’t understand much about it. Scientists have studied electricity for centuries, and they still have many unanswered questions! Listen to an electrical engineer explain some of the things we know, and still don’t know, about electricity.
All animals, including humans, need to sleep. Scientists have several theories that help explain why we sleep. In this episode of But Why, a child sleep psychologist describes the evolutionary theory of sleep and explains how sleep benefits the brain and body. Listen to learn more about the science of sleep and its importance for healthy growth and development.
Woolly mammoths were large, elephant-like creatures that lived tens of thousands of years ago, during the last great ice age. The thick, furry coat is one of several traits that gave woolly mammoths an advantage in a very cold environment. Today, the closest biological relative is the Asian elephant, which prefers warmer climates. Scientists were curious about the genetic variations between the woolly mammoth and the Asian elephant, and what might account for the differences between the two species. In this audio story, we hear from a scientist who studied the DNA from the extinct mammoth and compared it to its contemporary descendant. Listen to learn more about what researchers discovered.
Wildlife in the city? It may seem odd to hear the word “wildlife” linked to the word “city.” However, animals live wherever they can find food and shelter. Cities can provide both for many types of wildlife. Animals use their survival skills to turn just about any environment into their home. Listen to hear a scientist explain which animals can be found in suburbs and cities and how they adapt to these environments.
Wolves often get a bad rap, especially in fairytales. But are they really as bad as they seem? Yes, wolves are top predators, but there is much more to these awesome animals than simply their hunting habits. Listen to an expert explain fascinating details about wolves, from the complexity of their packs to how the dogs and wolves of today stem from the same extinct species.