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What If? Lab What if birds forgot how to build nests? Nests keep eggs and chicks safe from predators and the weather, and birds build them in amazing ways: from twigs, grass, mud, hair and even spider silk. Imagine every bird forgetting how to build one. Then meet the birds that already manage without, from cliff-ledge murres to emperor penguins.
What If? Lab What if insects vanished? Insects eat plants, and birds, mice and bears eat insects. In our forest food web, take the insects out and see who could go hungry and who could change. Then find out why scientists are counting insects carefully, and how people help them.
What If? Lab What if you had no teeth? Your teeth cut, tear and grind food into small pieces so you can swallow it. Imagine eating with no teeth at all! Find out what each kind of tooth does, how baby teeth make way for adult teeth, and how birds manage without any teeth, using a muscly stomach called a gizzard.
What If? Lab What if penguins could fly? Penguins are birds whose wings became stiff flippers for swimming. Their ancestors flew, but today's penguins are superb divers instead. Imagine a penguin that could fly: what would it need to change, and what might it lose underwater?
What If? Lab What if seeds could not travel? Seeds ride the wind, float on water, hide in fruit that animals eat, and cling to fur and socks. What if every seed simply dropped under its parent plant? Explore crowded seedlings, wind and animal helpers, and the burrs that gave people an idea.
What If? Lab What if there were no wetlands? Marshes, swamps and bogs are wetlands: places where water covers the soil or sits just below it. EPA compares them to natural sponges that soak up rain and floodwater and let it go slowly. They also clean water and shelter many birds and young fish. Imagine a world with no wetlands, and follow what might change.
What If? Lab What if dinosaurs still lived today? Most dinosaurs died out 66 million years ago, after a huge asteroid hit Earth. One group survived: birds, which scientists count as living dinosaurs. Imagine the other dinosaurs had survived too. Where could they live, what would they eat, and how would they fit into today's world?
What If? Lab What if you could see like an eagle? Some eagles can see about twice as much fine detail as people can. Their big eyes are packed with light-sensing cells, and many birds of prey have two extra-sharp spots in each eye where we have one. Imagine trading eyes with an eagle and find out what you would gain, and what eagles might not see at all.
What If? Lab What if you never slept? You spend about a third of your life asleep. While you sleep, your brain is busy sorting the day's memories and, scientists think, tidying itself up. Imagine never sleeping, then meet birds and dolphins that can rest one half of the brain at a time.
What If? Lab What if a city had no trees? Cities are full of roads, roofs and parking lots that soak up the Sun's heat. Street trees shade them, cool the air, catch rain and give birds a home. Imagine a city with every tree gone: hotter streets, more rain rushing down the drains and fewer birds. Then see how people plant trees to help.
What If? Lab What if mosquitoes disappeared? Nobody enjoys an itchy mosquito bite. But mosquitoes are also food for fish, dragonflies, birds and bats, and some even pollinate flowers. Some kinds can also carry germs that make people sick. Imagine every mosquito gone: what would we gain, what might we lose, and why aren't scientists sure?
What If? Lab What if migratory animals couldn’t reach their destinations? Every year, birds, butterflies, deer and pronghorn travel huge distances between their summer and winter homes. Along the way they need stopover places to eat and rest, and clear paths across the land. Imagine those stops disappearing or those paths blocked by roads and fences, then meet the wildlife bridges and protected places that help animals travel.
What If? Lab What if every animal were the same size? The smallest bird weighs less than 2 grams; a big elephant weighs more than three million times as much. Size decides what an animal can eat, how it keeps warm and how fast its body runs. Imagine every animal squeezed or stretched to one size, and see what would go wrong.