Desert, courtesy wikipedia

A desert is a unique biome that receives less than ten inches of rain a year.  Deserts are very dry, but they are not always hot.  There are two kinds of deserts: hot deserts and cold deserts.  The hot desert is the kind of desert we are most familiar with.  They can be very hot.  The Sahara Desert reaches daily temperatures over 110 degrees Fahrenheit regularly during the summer.  The hottest temperature every recorded on earth was in the Sahara:  136 degrees Fahrenheit.  That is very hot!  But even hot deserts are not always hot.  At night, temperatures can drop to 41 degrees Fahrenheit, even after reaching temperatures over 100.  During the winter, nighttime temperatures can drop below freezing.

Why do hot deserts get so cold at night?  Deserts are very dry.  Moisture in the air acts like a blanket and insulates the ground, keeping the heat in.  Since there is little moisture in the air in a desert, the heat escapes as soon as the sun goes down.  This is a special challenge to plants and animals because they have to have adaptations for surviving the cold of night and the heat of day.

Antarctica , courtesy wikipedia

Cold deserts are found in Antarctica, Greenland and near the arctic zones.  Winter temperatures average between 28 degrees Fahrenheit and 3o degrees.  Summer temperatures may reach 78 degrees.  They can actually get quite a bit of precipitation, usually as snowfall in the winter.  The soil is porous, which means it has lots of holes.  Water drains off the surface very quickly, so the soil is dry even after heavy rains or snow melts

Road Runner-wikipedia

They have a long neck, and long beak to help them stretch and balance.  Their legs are very strong and built for running.  Their feathers are black with white streaks and some brown.  Their coloration helps them blend in to the desert environment.

Road runners are omnivores.  They mostly eat meat, but they will eat plants.  They hunt snakes, other birds, small reptiles and amphibians and rodents.  They are very fast, fast enough to eat rattlesnakes!

First the roadrunner grabs the rattlesnake by its tail.  Before the rattlesnake can bite the roadrunner, the bird swings the rattlesnake around and pounds its head on the ground until it dies.

Roadrunners are well adapted to desert life.  Their colors blend in.  They hunt in the morning and evening.  In the heat of the day, they find shade to cool off.  They get most of the water they need from their food.  They also reabsorb moisture from their waste.  Salt builds up in a bird’s body when it digests food or sweats.  Most birds get rid of salt through their liquid waste.  The roadrunner would lose too much water this way.  They have a special gland near their nose to get rid of salt.

The Road Runner is also a famous cartoon made in 1948 by animation director Chuck Jones.

road runner,wikipedia

My mom says she saw lots of roadrunners hunting near the road when we used to live in Texas.  I hope I get to see a roadrunner someday.

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They are also very important to humans because of what is inside them and on them.  They are used a lot in classrooms to teach students about basic anatomy.  If you are interested in seeing what a frog looks like on the inside, you can dissect them online and you don’t even have to kill a frog!

The Choco Indians knew that some frogs had powerful poisons on their skin and used this to poison their arrows to make them more deadly.  Other frogs they used to spread on their skin when they cut themselves because it made the wound heal faster.  A long time ago, Chinese people used a medicine made from frog poisons to help the heart that works the same way our modern medicine does to strengthen heart contractions.

It is funny that in all these places thought of as “traditional” people recognized the value of frogs.  In the West, however, frogs were blamed for things like warts and witchcraft.  Maybe it was the West that was backwards because now scientists are finding many powerful medicines in frogs.  Here are some uses of frogs in medicine:

1. African clawed frogs were used to show if a woman was pregnant back in the 1930s.
2. A type of Australian tree frog may be used to make more powerful antibiotics that bacteria will have a hard time building a resistance to.
3. A pain killer that is more powerful than morphine but with less side effects can be made from the toxins made by the South American poison dart frog.
4. They may even be able to make a mosquito repellent from frog secretions that does not have the chemicals in our current sprays!

Amphibians really are amazing and very important to humans as well as the environment.

A frog that died of chytrid. Photo courtesy of wikipedia.org

Did you know that up 1/2 of all amphibians are in danger of extinction?  They are dying off at an alarming rate.  Amphibians are one of the first animals to suffer when there are changes in habitat.  Since they live on both land and in water, they are sensitive to problems in both environments.  This is why they are called a bellwether species.

The term bellwether came from the practice of putting a bell on the leader of a flock of sheep. The term is now used to describe an indicator of a complex of ecological changes. Bellwether species are also called indicator species and are seen as early warning signs of environmental damage and ecosystem change.  Bellwether Species

So what is causing the big amphibian die off?  Normally when animal populations are dying off, scientists look at habitat loss.  Habitat loss is a big factor in animals becoming endangered or extinct.  Without habitat, an animal has no home, no place to eat and no place to raise babies and no place to roam.

Habitat loss is affecting amphibians, but it is not the main problem right now.  The main cause of amphibian die off is a disease called chytridiomycosis, or chytrid.  Chytrid is a fungus which attacks the keratin in the frog’s skin, making it hard for them to breathe.  It started in Africa and can now be found in Australia, the Caribbean, the Americas and it is continuing to spread around the whole world.

To save amphibians, scientists and researchers have started the “Amphibian Ark.”  It is like Noah’s Ark in that they are taking a few animals of each species and protecting them to breed and study until they can be reintroduced in the wild.  Clorox is helping by donating bleach which kills chytrid.  Researchers are using it to sterilize clothing and equipment to keep from introducing the disease into new places while they collect animals.

The word amphibian means “double life” because they live in water and on land.

Do amphibians sleep? The answer is no. Sleeping is a certain brain activity when your body is motionless. Amphibians rest but don’t sleep.

You can’t get warts from frogs or toads.

Frogs don’t drink, they absorb water through their skin.

Frogs have teeth—toads don’t.

A few frogs have claws.

Caecilians are the only amphibians that are blind. They have no legs and live underground.

Many frogs live five to ten years. That’s a long time to find your prince!

The reed frog can change from a boy to a girl and back again.

A few species of frogs have live babies. Not eggs.

The frog’s tongue is attached at the front of its mouth.

Many amphibians can change their skin color to match their environment as protection.

A group of frogs is called a chorus.

The smallest frogs are about 10mm long. The largest frog, the Goliath frog, is 17 to 23 cm long. (They measure frog length from its nose to vent.)

Contributed by Sophia Hawthorne, age 8

It is not a book I would take to the lake to help me identify frogs.  It is almost like a cross between a field guide and a coffee table book because the photos are so beautiful.

It has a CD at the back of the book.  It tells you each kind of frog in the book with the sound it makes.  That helps you identify frogs by their noises.  Some species look very similar, but can be told apart by their song.  Also when you go out at night, you cannot always see the frogs around you but if you know their songs, you can identify them by that.

My favorite part of the book is the pictures.

We have found four of the kinds of frogs in the book: the bullfrog, the leopard frog, the Cope’s gray tree frog and the woodland toad.