THE SECRET LANGUAGE OF BEES

November 30th, 2009

 The secret language of bees

If you listen to a hive of bees, what you’ll hear is a droning, humming buzz. Sometimes it gets so loud that you might wonder how the bees hear each other at all. Well, the truth is: they don’t. Bees don’t need to hear each other, because they don’t talk to each other using sounds. Bees talk to each other by making smells, and by dancing!

In school science, you might learn that a hive contains a queen bee and thousands of worker bees. The big queen is surrounded by her “court” of about twelve bees. The queen’s court feeds her and cleans her, but if you look closely, you can also see them brushing their antennae against the queen’s body over and over again. They’re doing this because a queen produces something called pheromones, which are smelly chemicals, and different pheromones tell the bees in the hive to do different things. A worker bee in the queen’s court picks up the pheromones from the queen, and then uses her antennae to spread that smell around the hive.

Soldier bees make some important smells, too. Soldiers are older worker bees who guard the entrance to the hive from any insects or other animals who might threaten the hive or the babies inside. If a soldier senses danger, she releases a “warning” pheromone that tells all the other bees to come help with their stingers ready. School science teaches us to leave bees alone, and with good reason; if you swat at a bee and she releases that warning smell, you might have a whole hive of angry bees to deal with instead!

Even dead bees can communicate with the hive. When a bee dies, she releases a “dead bee” pheromone. This is important because a hive is crammed full of thousands of bees, and they have to keep it tidy and clean so that the bees in the hive don’t get sick. So as soon as a worker picks up that “dead bee” smell on her antennae, the smell guides her to the bee so she can pick it up in her jaws and carry it out of the hive.

But smells aren’t the only ways bees talk to each other; they also like to dance!

Bees need lots of nectar and pollen, so when a bee finds some, she needs to tell the other bees where to find it. She does this using something called the “waggle dance”. She stands facing in one direction and waggles her abdomen back and forth; each waggle represents a certain distance. Then she turns in a figure-eight and waggles again. She repeats this dance over and over, and the other workers watch her carefully. What’s she’s doing is giving them a complicated set of directions: she’s saying “when you leave the hive, turn this way and go this far, then you turn this way and go this far.”

But although the waggle dance is the most famous, there are many other dances that bees use to talk to each other. The “round dance” is a circular dance that says “hey, there’s food near the hive!”, a “vibrating dance” that tell lazy workers “hey, get up and do something!”, and even a shaky, staggering dance tells other bees “somebody please clean me!”

Bee talk is some real science fun. Imagine if you had to get your ideas across using only smells and dances. People might start to avoid you if you got really smelly, but what kind of dances would you do do to say “I’m hungry,” or “I don’t want to go to bed right now.” Maybe the next time you have trouble thinking of the right thing to say, you should just make like a bee and dance it out instead!

Post by Sarah

Cooking up Chemistry in the Kitchen!

November 23rd, 2009

Cooking up chemistry in the kitchen

Hey kids, when most people hear the word “chemistry”, they think of creepy laboratories with bubbling beakers of toxic goo. But chemistry can happen any time two different things react together to make something new, and there are fun science experiments that you can do right in your kitchen!

Experiment 1: Magic Mud

All you need for this experiment is some cornstarch, water, and a little bit of food colouring to show it off.

  1. Add 5 tablespoons of cornstarch to a bowl. Make sure you use something to scrape off the extra starch so you have a nice level spoonful.
  2. Add 3 tablespoons of water to the bowl.
  3. Add 3 drops of food colouring.
  4. Stir the mixture.

This mixture should be hard to stir unless you stir very, very slowly.  If it seems runny, add a few pinches more cornstarch. If it seems really dry, add a bit more water.

Now try squeezing a little bit of your magic mud between your fingers and rolling it into a ball. Then open your hand and watch what happens. Poke the top of your magic mud quickly, and your finger will bounce off. But if you sink your finger in slowly, the mud will swallow it up!  It acts like a liquid and a solid!

For a real adventure, try using the same measurements (5 parts cornstarch, 3 parts water) to make up a really big batch in a large pan, or even a kids’ swimming pool!  If you run fast enough, you can actually run across the top of the magic mud. Just don’t slow down, or you’ll find yourself sinking into the goo!

Experiment 2: The Incredible Giant Hand

For this experiment, you will need baking soda, vinegar, and a rubber glove. If you don’t have one, you could use a balloon to make The Incredible Giant Head.

  1. Use a marker to draw hair on the rubber glove (or a face on the balloon).
  2. Carefully add a few spoonfulls of baking soda to the glove.
  3. Pour some vinegar into the glove.
  4. Tie the glove closed, like you would a balloon. Shake it around a bit.

Now watch what happens. The hand (or head) will grow!

When the solid baking soda and the liquid vinegar meet, they react to form a gas called carbon dioxide. They make so much of it that it will blow up your balloon for you.

Experiment 3: Acid or Alkali

For this experiment, you need some beetroot or red cabbage. It also provides you with a tasty snack.

  1. Have an adult help you boil the cabbage or beetroot until the water changes colour.
  2. Collect some of the coloured water.

Scientists use something called pH indicator to measure how acid or alkali something is. Different acids and alkalis will make the indicator change different colours.

You’ve just made pH indicator. Have an adult help you test small amounts of your coloured water with acids and alkalis around the house. Vinegar, juice, household cleaners, antacid tablets, and baking soda are good places to start. The more acidic something is, the lower the pH number. See if you can figure out the pH of your test subjects:

     pH           Colour

      2               red (very acidic)

      4               purple

      6               violet

      8               blue

      10             blue-green

      12             yellow-green (very alkali)

And the best part about this experiment is that you can eat the vegetables you cooked! Now that’s fun science!

Post by Sarah

A Romp Through a Rainforest

November 9th, 2009

rainforest

Hey kids, do you know where you can find more living things in one place than anywhere else in the world?  In a tropical rainforest!

Rainforests are exactly what their name suggests: warm, dense forests that are very wet.Tropical rainforests are found close to the Earth’s equator, and they are home to millions of plant and animals. In school science, we can learn the four layers of the rainforest.

Towering above all the other parts of the rainforest are emergents: giant trees taller than any other in the rainforest that stick up above their neighbours. Emergents are homes to many birds and insects.

The canopy is the leafy part of the rainforest, made up of the tops of the trees. The canopy grows so thick and close together that rain falling on it can take 10 minutes to reach the ground!  Many amazing plants and animals are found here, including sloths. Sloths have long toes that they use to hang upside down from branches; they spend most of their lives upside-down, and will eat, sleep, and even give birth upside down!  Sloths are also famous for being the slowest animals on earth. They are so slow that algae grows in their fur and turns them green!

Under the canopy but above the ground is the understory of the rainforest. It consists mainly of the trunks of trees and the vines and other plantlife that grows over them. Many flowers grow in the understory, and thousands of birds and butterflies find their food there.

Finally, we reach the lowest part of the rainforest: the forest floor. It is home to millions of insects, and some of the largest animals in the rainforest also live there.

School science tells us that it’s important to preserve the rainforest because of all the plants and animals that live  there, but one of the most interesting facts about rainforests is that the trees also provide much of the air that we breathe! Rainforests are also important because the cures to many illnesses have been found in the plants that grow there.

Here are some other interesting facts about tropical rainforests:

The largest butterfly in the world is the Queen Alexandra’s Birdwing butterfly from the rainforests of Papua New Guinea. This massive butterfly has a wingspan of 30 cm, and it’s also poisonous! The caterpillars eat a poisonous rainforest plant, which means that any predators that try to eat a Queen Alexandra’s birdwing get very sick, and soon learn to leave all of them alone.

The rainforests of Sumatra are home to the largest flower in the world – which is also the smelliest.  The corpse flower has a blossom over a metre wide, and it gives off a stench like rotting flesh that can be smelled up to 800 metres away!

The Congo rainforest in Africa has its very own unicorns! Okapi are deerlike animals related to giraffes, with striped legs like a zebra. They have two horns on their heads, but if you look at an okapi from the right angle, the two horns look like one. This earned them their nickname of “African unicorns.”

And the coolest thing about rainforests is that there are so many plants and animals in them that we haven’t discovered them all yet! Maybe you can visit a rainforest and discover a new species someday.

Post by Sarah

Mysteries of the Deep

November 2nd, 2009

ocean

Hey kids, what do you think is the most unexplored part of our planet?  It’s not the depths of the rainforest. It’s not the burning deserts. It’s not even the frozen Arctic waste. The most unexplored parts of our planet are our oceans!  We’re just beginning to realize what kind of incredible mysteries are hidden in the deep, dark waters.

Our oceans make up a huge part of our planet – over 70% of the Earth’s surface is covered by them! They help control the temperature of the planet, shape the weather, and are home to millions of living things.

The deepest part of our planet is the Mariana trench, near Japan and the Philippines. At it’s deepest point, it reaches 10,924 metres (or 6.78 miles) deep. That means if you were to take Mount Everest, the highest mountain on Earth, and stick it at the deepest part of this trench, there would still be more than 2 kilometers of water over the top of it!

Fortunately, scientists have invented special deep water research cameras and vehicles that can reach into the cold, dark, high-pressure world of the deep sea. And what we’re starting to discover is that these dark, deep, freezing waters are filled with living things. Go down deep enough, and the living things you find look like aliens from another world; it’s discovering these strange creatures that makes science fun!

Imagine yourself stranded on the bottom of the ocean, with cold black water all around you. Suddenly, you see a light wiggling around in front of you. You’re drawn toward it, and wonder if maybe it’s something good to eat. You reach for it… and find yourself face-to-face with a mouthful of razor sharp teeth! You’ve just met an anglerfish.

An anglerfish is a hunter whose body is camouflaged to look like the floor of the ocean. In the middle of its head is a long tentacle with a sac on the end filled with glowing bacteria. The anglerfish hides itself on the ocean floor, and wiggles its tentacle around. Unsuspectitng fish are attracted to the worm-like tentacle, thinking it might make a tasty meal, and snap! They are chomped up by the anglerfish’s jaws, which look just like a mouth full of knives!

Have you ever seen those little grey pillbugs that you can find in the garden? They look like tiny grey tanks, and roll up into an armoured ball if they are threatened. Well at the bottom of the ocean, you can find an animal that looks just like one of those pillbugs – only it’s over a foot long!

But one of the most fearsome creatures in the ocean is the famous giant squid. For many years, people thought the giant squid was just a legend. Then whale watchers started to notice marks on the sides of some whales, like they’d been caught by a suction cup that was the size of a dinner plate! Finally, the bodies of some squid washed up on the shores of Newfoundland, and the squid went from science fiction to science fact! They can grow up to 13 metres long, and are wicked predators, snaring prey with the serrated suction cups on their tentacles and devouring them with their sharp beaks.

Even though we think we’ve explored the planet, we’ve really just scratched the surface. There’s a whole world left to explore under the sea!

Post by Sarah