<p>A Moment of Science is a daily audio podcast, public radio program and video series providing the scientific story behind some of life's most perplexing mysteries.</p>


        Why do airplanes sometimes leave contrails behind, and what are they exactly?
      

What are contrails?


        Do you prefer the jolt of coffee or a more gentle start to your day with tea?
      

Do you start your day with tea or coffee?


        Situs inversus totalis means that all the organs, blood vessels, and nerves in the chest and abdomen are flipped to the opposite side.
      

When every day is opposite day for your organs


        Normally you’d just see waves coming in parallel to the shore. But what if there were also waves moving perpendicular to the shore?
      

Why do square waves happen?


        A grave in Cyprus from 7500 BC shows a furry feline and human owner buried together. It’s the oldest known site of a tame cat.
      

Humans have been hanging out with cats for almost 10,000 years


        How did dinosaurs keep themselves cool?
      

Prehistoric air conditioning


        Did you know it’s possible to have a gene mutation that really does make bumping into furniture or even getting surgery totally painless?
      

Genetic mutation and pain


        What makes walking uphill so much harder?
      

Walking uphill is hard work


        Have you ever wondered why giraffes have such long necks?
      

Why do giraffes need such long necks?


        Scientists think that as many as a billion people around the world could be newly exposed to the diseases spread by mosquitoes within the next fifty years as global temperatures rise.
      

How mosquitoes will be impacted by global warming


        This small species lives throughout southern China, from high eastern Tibetan mountains to low coastal mountains, preferring forests and shrubby habitats. And its most interesting feature is its tusks.
      

The unique species of the tufted deer


        There’s a big gap between how we act in virtual reality and how we act in real life, as scientists who did an experiment focused on yawning found out.
      

Virtual reality and yawning


        We've heard a lot about how antioxidants can help prevent disease. Does that mean we should eat as many antioxidant-rich foods as possible?
      

Not all antioxidants are the same


        Most moth species are active at night. It must be really dangerous to be a moth. Luckily, they've developed a few ways to protect themselves.
      

Moths use acoustic camouflage


        Scientists think that animals evolved the ability to detect bitter tastes in order to avoid things that are harmful or even poisonous. So why do we like coffee?
      

Why do humans like coffee?


        Where most of us are concerned, the question is not whether we would hurt a fly but whether we could.
      

What makes swatting a fly so hard?


        In October, 2017 astronomers at Haleakala Observatory in Hawaii discovered something strange. It was an object, moving through the solar system too fast to have been captured by the sun’s gravitational pull.
      

The mysteries of Oumuamua


        Did you know that compared to creatures such as dogs and cats, humans can distinguish millions more shades of color?
      

Red cone, green cone


        There's evidence that the northern lowlands of Mars are the basin of a huge ocean that existed more than 3 billion years ago, and covered about a third of the planet's surface.
      

Tsunamis in the oceans of Mars


        Root rot is a condition of indoor and outdoor plants. Root rot may be caused by poorly drained or overwatered soil, or soil-borne pathogens and nematodes.
      

Fighting back against root rot


        Microbes are everywhere, from the deepest ocean to the highest mountaintop. They're also in the air all around, riding the breeze up, up, up into sky.
      

In the atmosphere, microbes are walking on air


        But a cheetah isn’t the fastest animal in the world, even though a lot of people think it is. The animal that can move the fastest is actually a lot smaller: the Dracula ant.
      

The ant with moves like a cheetah


        Background white noise can help some peoples’ sleep quality by minimizing the length of time it takes them to get to sleep. So, what exactly is white noise?
      

Background noise and sleep quality


        Mid-Atlantic states such as North Carolina, Virginia, and Maryland have been hit particularly hard by rising sea levels
      

Different rates of sea level rise


        Do other species have healthcare?
      

Ant doctors


        Our attitudes might affect us more than our genes do.
      

How your attitude affects your body


        Does your pet give you the evil eye when they get fed a few minutes late? Its like they know...but do they?
      

Can animals tell time?


        The Gulf Stream is a current of warm water in the North Atlantic Ocean that travels up the Eastern coast of North America. Media reports have raised concerns that it may collapse as the climate warms due to human activities like burning fossil fuels.
      

Could The Gulf Stream collapse?


        Like a science fiction time traveler, an arctic plant of the late Pleistocene age, over 31,000 years old, was resurrected after a long frozen sleep.
      

Ice age plant survived the big chill


        Figs have their thousands of individual flowers folded up inside them, so they can't rely on bees or wind to pollinate them with a male fig's pollen. That's where the fig wasp comes in.
      

Every time you eat a fig, remember a fig wasp lost its wings


        Has your brain been feeling foggy lately? Or maybe, smoggy? If you live somewhere affected by air pollution, there might be a connection.
      

Study links air pollution and a decline in cognitive function


        Scientists once thought that aging and death were the inevitable fate of all complex living things. But then, by accident, they discovered they were wrong.
      

The jellyfish that never grows old


        On today's Moment of Science, we'll be sniffing our way through a controversial culinary conundrum: the great cilantro debate.
      

The great cilantro debate


        Grandmother elephants are important for the survival of baby calves.
      

Elephant grandmothers means more elephant calves


        English is full of phrases that connect appearance to taste. However, scientists have been discovering that the connection between the two runs deeper than simple metaphors.
      

Looks delicious! The connection between appearance and taste


        Sometimes, when a frog eats a large insect, you can see it squirming in the frog’s belly, desperate to escape. Lack of air, acids, and digestive enzymes seal its inevitable doom.
      

Escaping alive from a frog's stomach


        Scientists looked at the nestbox choices of pied flycatchers after the birds observed the "success" of nesting great tits.
      

Copy your neighbors, but only when they're successful


        Is there a reason operating rooms are always so cold and drafty?
      

Why are operating rooms so cold?


        Colorful or plain, skinny or chubby, big or small, the nearly 2,000 species have it all.
      

Starfish are all heads, no tails


        Vaccine skeptics might see vaccines the way they do because they tend to overestimate the likelihood of rare negative events.
      

Skeptics think about vaccines differently


        How do scientists figure out even basic facts such as whether an animal walked on land or swam in the sea?
      

Walked or swam? An index can answer


        Researchers classify an animal behavior as play when it doesn’t involve an external reward, such as food, seems to serve no purpose, occurs repeatedly, and happens when the animal is relaxed and not facing threats.
      

Play and the brain


        Scientists find clues to how the earth's climate is changing by looking to the past.
      

What we can learn from ancient climate records


        Demand for rare earth elements is soaring, and it will continue to grow in the future.
      

Tetrataenite as a solution to the rare earth crisis


        When the bismuth combines with the trace amounts of sulfur in your saliva and in your gastrointestinal tract, it reacts to form a black substance called bismuth sulfide.
      

The effects of bismuth in Pepto Bismol


        King Tutankhamen of Egypt has fascinated people ever since archeologist Howard Carter discovered his splendid tomb in 1922.
      

King Tut's dagger from space


        Bitterness, like sweetness or saltiness, is one of the major taste sensations. And while it makes our food flavorful, detecting bitterness can sometimes be a warning that we’re eating something toxic.
      

Where does bitterness come from? Ask the sharks


        What's your earliest memory?
      

Remembering the past, as a baby


        It takes much less time for the sun to light up the sky at dawn than it does for all the light to disappear after the sun sets at dusk.
      

Why are sunrises faster than sunsets?


        If you drink a glass of ice water on a hot day, what temperature is the ice?
      

The temperature of ice on a hot day


        There are some biological differences between the sexes, but do they extend to the brain?
      

Do brains differ with biology?


        Where does color come from?
      

Mauveine: The first synthetic dye


        In 2019 a team of Israeli scientists published evidence that the evening primrose plant can detect the specific sound vibration frequencies of the buzz of an insect’s wings.
      

Can plants hear?


        Every student who has ever taken a course in neuroscience or psychology has heard of Patient HM.
      

Patient HM: Henry Molaison and the neuroscience of memory


        We share a lot of genetic material in common with our chimpanzee relatives, and maybe some personal characteristics too.
      

Monkeys can be petty, too


        One frosty morning you awake to a blanket of fresh snow. Adventure awaits! Do you go skiing? Skating? Building snowmen? Or you could do some physics!
      

Snowshoes and physics


        French scientists tested dogs to see if they could recognize the faces of other dogs on a computer screen.
      

Dogs can recognize their own species


        While not an ordinary part of the cuisine of the United States, insects are a common food source for millions of people around the world. It might be time Americans reconsidered their lack of bug-based eating.
      

Being able to stomach bugs


        In evolutionary theory, an inherited trait is favored by natural selection when it helps an individual to produce more offspring than its competitors.
      

Are eyes evolving?


        Modern birds are the descendants of dinosaurs. Specifically, paleontologists have shown that birds evolved from a group of two legged dinosaurs called theropods.
      

The proteins in dinosaur feathers


        June 1969. Not one airliner but two, plus the pilot of an Air National Guard fighter plane, report being harassed by a team of UFOs.
      

UFO attack or meteor fragments?


        Coffee and cacao beans are fermented. Similar to wine, the flavor of the beans is determined by the type of yeasts and microorganisms present.
      

Beans get their flavor from yeast


        From DIY oven cleaner to removing odor from rugs, baking soda, or sodium bicarbonate, has long been known as an essential home cleaning agent.
      

Solving a new problem with an old remedy


        A "niche" is an organism's special "slot" in an ecosystem that allows it to co-exist with other species.
      

Think like a penguin: Finding your niche


        When someone moves, fluid sloshes inside the ears’ semicircular canals. The fluid tugs at tiny strands of hair.
      

Going for a spin and getting dizzy


        The Apollo astronauts were at risk of something many people don't know about. The Sun.
      

The risk astronauts take with the Sun


        We all know someone who goes for a walk in the woods, and comes back with many ticks crawling on them.
      