What flies through the night, silently guarding and protecting our world from evil? Batman? Try…a bat. Like Batman, bats are widely misunderstood and vilified. Not only do bats eat pesky insects like mosquitoes and crop pests, they disperse seeds and pollinate plants, and have even inspired the design for robotic airplanes. Help dispel the myth that bats are dangerous villains and spread the word why they, instead, deserve a hero’s welcome – and our protection.
An experiment showed that the amount of nurturing a mother rat provides its newborn baby plays a part in determining how that baby responds to stress later in life.
The pups of nurturing moms turned out less sensitive to stress because their brains developed more cortisol receptors, which stick to cortisol and dampen the stress response.
The pups of negligent moms had the opposite outcome, and so became more sensitive to stress throughout life. These are considered epigenetic changes, meaning that they effect which genes are expressed without directly changing the genetic code. And these changes can be reversed if the moms are swapped.
But there’s a surprising result. The epigenetic changes caused by one single mother rat were passed down to many generations of rats after her. In other words, the results of these actions were inheritable.
Did you know that songbirds’ brains actually have so-called “song circuits” that are active when the birds sing. These circuits also respond to the song of a bird’s own species more strongly than to other species’ songs. The theory is that a bird’s genes guide development of brain circuits that relate to singing and the ability to learn songs. Then, exposure to songs shapes those neural circuits to produce the songs that are typical to that species.
Genetically encoded or innate behaviors aren’t unique to songbirds. They’re widespread in the animal kingdom. Other spectacular examples include the long-distance migrations of monarch butterflies and salmon.
So what does this mean for humans? Are we also born with innate information written into our genomes that helps shape our neural circuits, and ultimately results in something we know? Could there be some knowledge that is unique and intrinsic to humans as a species?
We have our friendly neighborhood dung beetles to thank!
Capable of burying 250 times their body weight in a single night, these valiant insects make quick work of an endless stream of feces.
Over 7,000 known species of dung beetle run clean-up duty across six continents —everywhere except Antarctica.
Most dung beetle species fall into one of three main groups: rollers, tunnelers, and dwellers.
Dung rollers sculpt a ball of dung, and using their back legs, quickly roll it away from competitors. Potential partners jump on the ball, and once the ball-maker has selected their mate, the pair dig their dung ball into the soil. Once it’s been buried, the female lays a single egg within the dung ball.
Tunnelers have a different approach. Digging underneath a pat, some drag dung down into the soil and pack it into clumps known as brood balls, dung balls, or dung “sausages,” depending on their shape and size. Male tunnelers sport a spectacular array of horns to fight each other for control of these tunnels, which they then defend until the female’s laid her egg. Some male tunnelers avoid the fray by masquerading as hornless females and sneaking into tunnels to mate while the guardians’ heads are turned.
The third group of dung beetles, dwellers, take the most straightforward approach, laying their eggs directly into a dung pat. This makes their offspring more vulnerable to predation than those of the tunnelers and rollers. As the larvae feed, they riddle the dung pat with tunnels, leaving remains that are quickly colonized by bacteria and fungi and weathered away. Inside a tunnel, ball, or pat, once the larvae hatch, they consume the dung before metamorphosing into a pupa and then an adult beetle.
Dung beetles also play important roles in agricultural systems. Livestock, like cows and sheep, produce huge amounts of dung, which contains nutrients that can benefit plants. The beetles break up the dung and tunnel it deep into the soil, bringing the nutrients into close contact with plant roots. Their services to farmers have been valued at $380 million a year in the US03:51and £367 million a year in the UK. Dung beetles can even help us battle global warming by reducing greenhouse gas emissions associated with farming. Microbes living in oxygen-poor livestock dung produce methane, a potent greenhouse gas. But beetles oxygenate pats when they tunnel into them, preventing the microbes from producing methane. The dung beetle spreads seeds, helps farmers, and fights climate change —and accomplishes it all simply by doing its business.
Maybe next time you come across some dung in the forest or a field, you’ll be tempted to take a closer look.
Imagine aliens land on the planet a million years from now and look into the geologic record. What will these curious searchers find of us? They will find what geologists, scientists, and other experts are increasingly calling the Anthropocene, or new age of mankind. The impacts that we humans make have become so pervasive, profound, and permanent that some geologists argue we merit our own epoch.
For example, people’s farming, fishing, and forestry will also show up as a before and after because it’s those kinds of activities that are causing unique species of plants and animals to die out. This die-off started perhaps more than 40,000 years ago as humanity spread out of Africa and reached places like Australia, kicking off the disappearance of big, likable, and edible animals. This is true of Europe and Asia, with the woolly mammoth, as well as North and South America, too. For a species that has only roamed the planet for a few hundred thousand years, Homo sapiens has had a big impact on the future fossil record.
That also means that even if people were to disappear tomorrow, evolution would be driven by our choices to date. Something to think about….
Maybe your kids already love science. If so, great! If not, these creative strategies can help. Ready to spark a love of science in the students near you? Here are five ways to get started. Encourage students to pick one action from the list below and try it out.
1. Upgrade the science fair project. Before you create that foaming tabletop volcano, check out these curiosity-powered experiments from Make, the Exploratorium, and mad scientist Grant Thompson. Which one will you try next? Science fair optional.
2. Join the citizen science brigade. ”Citizen scientists” are volunteers who help to collect and analyze research data in fields ranging from archaeology to zoology. Explore citizen science project options here, here, and here.
3. Invent a solution to a real-world problem. In Kenya, student Richard Turere invented a solar-powered way to prevent lion attacks. In Malawi, a young William Kamkwamba harnessed the wind to power his family’s home. In Hong Kong, students in Cesar Harada‘s class work together to address environmental threats to the ocean. Now it’s your turn. What problem do you care about enough to solve — and how will you do it? To filter options quickly, try the Google Science Fair’s Make Better Generator.
4. Research quirky, open-ended questions. Science is the story of humans asking ”why?” “how?” and “what if?” about what they observe. What questions will you ask of the world? To get inspired, check out these questions no one knows the answer to (yet).
5. Explore science fiction. Futurists believe that science fiction can predict the future — or at least provide us with a way to imagine and prototype the future. Do you agree? Before you decide, read one of the short sci-fi excerpts shared here, or watch a video from the Superhero Science series.
You may take them for granted, but your teeth are a marvel. They break up all your food over the course of your life, while being strong enough to withstand breakage themselves. And they’re formed using only the raw materials from the food they grind down in the first place. What’s behind their impressive strength?
Teeth rely on an ingenious structure that makes them both hard and tough. Hardness can be thought of as the ability to resist a crack from starting, while toughness is what stops the crack from spreading.
Very few materials have both properties. For instance, glass is hard but not tough while leather is tough but not hard. Teeth manage both by having two layers: a hard external cap of enamel, made up almost entirely of a calcium phosphate, and beneath it, a tougher layer of dentin, partly formed from organic fibers that make it flexible.
Today, the ability to consume diverse forms of food enables mammals to survive in habitats ranging from mountain peaks and ocean depths to rainforests and deserts. So the success of our biological class is due in no small measure to the remarkable strength and adaptability of the humble mammalian molar.