What exactly is a tortoise? Tortoises are reptiles that live on the land, whereas turtles live in the water for the most part.

Desert tortoises (Gopherus agassizii) are fascinating creatures only found in the deserts of the southwestern United States and northern Mexico. They have large, scaly front legs for digging.Their shell or carapace is dark brown with deep lines.

We met this desert tortoise at a class at the Desert Botanical Garden in Phoenix.

We learned a lot about tortoises in the class, including that you should never pick up a wild tortoise. It turns out that one way a tortoise survives in such a dry environment is by holding urine in its bladder and recycling the water from it. If someone picks up or otherwise scares a desert tortoise, part of its defense is to urinate. Studies have shown that unless the tortoise can quickly replenish the supply of water that it lost by urinating, that it is likely to dehydrate and die. Just shows that simple human curiosity can be fatal to other creatures and that we need to be respectful of wild animals.

We also learned desert tortoises that have been brought into captivity should never be returned to the wild because they potential carry diseases that might infect wild tortoises.

Other desert tortoise facts:

• They can live up to 100 years.
• The females don’t lay eggs until they are at least 15 years old.
• They dig burrows in the soil to stay cool in the hot summer.
• They eat desert plants such as cacti.
• They hibernate in the winter.

Activity 1. Desert Tortoise Drawing

Gather:

• Art supplies such as crayons, colored pencils and markers
• Photographs of desert tortoises, from books or the Internet
• Drawing paper
• Optional: coloring sheets to print out

Encourage the children to examine the photographs closely and draw a scene with a desert tortoise. For more formal instructions, try how to draw a desert tortoise.

Activity 2. Learning the life cycle

Like many reptiles, tortoises hatch from eggs. You can see the eggs, hatching and young tortoises in this video.

As the narration points out, the young tortoises spend time after hatching absorbing the remains of the egg yolk as an important source of nutrition.

Young tortoises grow slowly over a period of years. There are physical differences between the males and females in the shape of the carapace, etc.

For much more information, see this detailed life cycle of desert tortoise.

So, do you think they are cute and that you might want to have a desert tortoise as a pet?
Consider these facts first:

1. You will probably have to leave your tortoise to someone in your will, because if you care for it well, it is likely to outlive you.

2. You won’t be able to see it all winter, because it needs to hibernate.

3. You need to supply it with specially selected food. The fruits and vegetables we eat contain too much water and chemicals that can harm tortoises.

4. You will need to find someone else to care for it if you can no longer do so. You can’t just let it go because it won’t survive and it is likely to carry diseases that will harm other tortoises. Besides, it is illegal to do so.

The Arizona Game and Fish Department has more about rules and care of desert tortoises.

As with any animal, it is really important to do your research before adopting a pet. With care, many people are quite successful when they adopt captive-bred animals.

If you are really interested in desert tortoises, “get out of your shell” and learn more about them. Then, pass on what you find out to your friends.

Be sure to check out Desert Tortoises by Elizabeth Thomas and other great books about desert tortoises.

Reading level: Ages 4 and up
Library Binding: 24 pages
Publisher: Capstone Press (August 1, 2011)
ISBN-10: 1429666455
ISBN-13: 978-1429666459

Book was supplied by publisher for review purposes.

Looking for STEM books for children? Check the STEM Friday round up each week for recommendations.

STEM Friday is hosted today at Simply Science.

Camouflage and invisibility are two very different things. Camouflage is the use of color or other aspects of appearance to help an object blend with its environment. Invisibility, on the other hand, is changing the way light reflects or refracts when it hits an object and thus preventing the light from reaching our eyes. We literally can not see an object that is invisible.

Becoming Invisible: From Camouflage to Cloaks tells how scientists have been able to bend electromagnetic waves that are near relatives of visible light (see Exploring Light and its Relatives Part I and Part 2) with special man-made materials called metamaterials. Using metamaterials made of metal and fiberglass, scientists have been able to develop “cloaks” that bend microwaves and infrared light around an object, hiding it from detection. Very cool!

Activity 1. Hiding with color – camouflage for younger children

Read one of the books suggested below to introduce the idea of camouflage.

Gather:

• Fabric swatches of different colors and designs
• Painter’s blue tape (doesn’t leave a residue when it is removed, but it is more expensive) or masking tape
• Suitable area to play hide and seek, indoors or out

You might want to sort the children into teams if you are working with a large group. You will need enough swatches of fabric so that each child or team can hide a few different swatches. Make loops of tape with sticky-side out and then apply a few to the back of each swatch. Now select a child/team to be the hider. They will hide the swatch in plain sight in the play area by taping the swatch to items while the other children, who will be the seekers, close their eyes or wait in another area. When the hiders have applied their swatch, have the seekers come look for it. Once they have found it, change roles. The goal is to find a background object that matches the color close enough that the fabric is difficult to see, and thus takes longer to find.

Activity 2. Hiding with color- camouflage for older children

Gather:

• Paper
• Art supplies such as markers, crayons, colored pencils, etc.
• Painter’s blue tape (doesn’t leave a residue when it is removed, but it is more expensive) or masking tape (optional)
• Suitable area to play hide and seek (optional)

For older children, have them create their own camouflage patterns for different settings. You could also have the children do the hiding activity (1), but substitute their own designs on paper for the fabric swatches. Or figure out an experiment to test the effectiveness of various camouflage designs.

Activity 3. Making glass “disappear”

We don’t need high tech metamaterials to make an object invisible. We can hide a piece of Pyrex® glass by immersing it in a material that has a similar index of refraction, Wesson® oil.

Gather:

• small Pyrex® glass bowl
• A larger glass bowl
• Wesson® oil or baby oil, or a mix of the two

Place the smaller bowl inside the larger bowl. Fill them both with Wesson® oil, baby oil, or a mix of the two. Once covered with oil, the smaller Pyrex® bowl should disappear from view.

See a similar activity using a Pyrex® stirring rod and explanation from Exploratorium

Activity 4. Make jelly marbles disappear in water

Obtain some jelly marbles from science supply stores, for example from Steve Spangler. Soak the jelly marbles overnight in water. Then fill a clear glass container with water. When you drop in the soaked jelly marbles, they will disappear.

Jelly marbles are polymers that absorb water. When they are swollen with water, they have the same index of refraction and disappear when you place them in water.

This video shows examples of both of the index of refraction activities:

Isn’t that amazing?

If you try any of these activities, be sure to let us know what you find out.

Related camouflage links:

• Brain Pop Jr. has a unit on camouflage
• The Invisible Man
• The Arts of Deception at Mongabay.com (has ads)
• Survivors: How Does Color Protect Insects from Predators?

Children’s books about camouflage (title links go to Amazon):

	Becoming Invisible: From Camouflage to Cloaks (Great Idea) by Carla Mooney (is for ages 8 and up) My review
	Hiding in Deserts (Creature Camouflage) by Deborah Underwood My review
	Animal Planet Weird and Wonderful: Show-Offs (Animal Plant Weird & Wonderful) by Margaret McPhee is not just about camouflage, but all the ways animals use color. My review
	Where in the Wild?: Camouflaged Creatures Concealed… and Revealed by David Schwartz and Yael Schy, with photography by Dwight Kuhn My review
	Where Else in the Wild? is a enchanting combination of poems by David M. Schwartz and his wife, Yael Schy, and photographs by Dwight Kuhn. My review
	How to Hide an Octopus and Other Sea Creatures (Reading Railroad) by Ruth Heller
	How to Hide a Butterfly and Other Insects (Reading Railroad) by Ruth Heller.
	What Color Is Camouflage? (Let’s-Read-and-Find-Out Science, Stage 2) (Let’s-Read-and-Find-Out Science, Stage 2) by Carolyn B. Otto and illustrated by Megan Lloyd

We are excited that Arizona is participating in a big way this year. The Arizona SciTech Festival will showcase science, technology and innovation through a series of over 150 free events taking place between Jan. 25 and Mar. 14, 2012 statewide.

According to their news release, over 250 organizations have partnered together to promote Arizona’s participation in science, technology, engineering, and math (STEM) through a series of hands-on activities, workshops, conversations, debates, exhibitions, concerts, guided walks and tours.

Featured Events Include:

• Jan. 25 – 26 Aerospace and Defense Requirements Conference (Not free)
• Feb. 3-5 Glendale Chocolate Affaire-The Science of Chocolate
• Feb. 4 Arizona Science Center’s Innovations in Bioscience
• Feb. 10–12 Mesa’s Take Flight Celebration
• Feb. 14, 16 AZ Renaissance Festival’s Discovery Days
• Feb. 16 Chandler’s Tech Crawl
• Feb. 16 Tempe’s The Science of Fun
• Feb. 18 Tucson’s Science in the City
• Feb. 19–20 Challenger Space Center’s John Glenn Anniversary Event
• Feb. 21 A Day of Dean Kamen
• Feb. 25 Arizona State University’s EX-STATIC at New College
• Feb. 25–26 Scottsdale’s Science of Baseball
• Mar. 3 Arizona State University’s Night of the Open Door
• Mar. 6 University of Arizona’s Innovation Day

Wander through the Arizona SciTech Festival website to find many more fantastic activities. (There are almost too many to choose from.)

If you aren’t going to be in Arizona in time to take part, try these related festivals:

• Bay Area Science Festival- going on now!
• Philly Science Festival
• NC Science Festival
• San Diego Science Festival
• Cambridge Science Festival
• Flagstaff Festival of Science

If you go to any science festival events, please drop us a comment and tell us about it.

The Great Backyard Bird Count is easy and fun. Be sure to visit the website and read all the instructions, but in a nutshell you need to set aside at least 15 minutes on at least one of the days, gather a paper, pencil and a set of binoculars (optional) and count the birds you can see in your yard or neighborhood. When you are finished, you enter the data in the online form at the website (open only during the count). Then check back to see what birds others have counted in your community.

Related activities:

1. Bird Watching

Bird watching is a popular and engaging activity. You don’t need to travel or have expensive gear to bird watch. You can simply look out the window and spot birds. Birds are interesting because they are colorful, active and can be found almost anywhere. At various times of year birds are migrating, singing, building nests and raising babies. There’s always something exciting going on amongst your neighborhood birds.

Are you a complete beginner? Learn your birds by figuring out a few at a time, using field guides and websites. Here are some popular field guides:

Keep a notebook full of drawings and notes next to your favorite birding window. Over the course of a year you will begin to recognize the regulars and also new birds.

Many communities offer bird hikes and birding classes. Check you local newspaper and do a few Internet searches for local birding clubs and events.

2. Bird Feeders
What can you do to encourage birds? Many people start by making simple bird feeders, such as the classic pinecone rolled in birdseed. Many of the crafts you see suggest using peanut butter, which is not fun at all for children with peanut allergies. Try this alternative that actually attracts a larger assortment of birds as well.

Gather:

• dry, clean pine cones, enough for all participants
• lard (available in most grocery stores) at room temperature
• bird seed
• ribbon or string
• plate or tray to spread seed on
• butter knife or craft sticks

Spread the bird seed on a tray. Tie the string or ribbon on the pine cones to serve as a hanger.  Have the children “butter” the pine cones with lard, either using their fingers or craft sticks, filling in the cracks. Then roll the filled pine cones in the bird seed, which should stick. (Note:  I found it was easier to tie the strings first, but you can also do it last). Hang the pine cones in a tree that you can watch and wait for the birds to discover it.

You can make another simple feeder by stringing fruit such as raisins, grapes, cherries or orange sections on a bit of twine or string and hanging it out. Just be careful and find out what works best in your region because scattering food for birds can also attract unwanted guests, including bears in some areas!

Often you can reduce the number of unwelcome guests by choosing what type of food you present and how. For example, niger thistle seed attracts colorful birds like finches and doves, but not pigeons or rats. Check with your local Audubon Society or other birding resources for recommendations.

3. Nesting Materials
Making cards full of nesting materials can be a fun project that is easy to do with supplies from around the house.

Gather:

• index cards or roughly three-inch by five-inch pieces of card stock, enough for all participants
• hole punch or scissors
• yarn, preferably wool or cotton
• thread
• hair or anything else you think a bird might use in its nest
• string or ribbon to hang card

Brainstorm about what might be useful to a bird. Poke holes in the index cards with a hole punch or cut holes with scissors (with an adult’s help). Tie a 12-inch piece of string, yarn or ribbon through one hole to serve as a hanger. Loosely stuff the rest of the holes with a variety of nest making supplies, making sure the birds can pull it out fairly easily. When you are finished, go outside and hang the cards in bushes or trees where the birds will find the materials. Check over time to see which materials they chose first, second, etc. Refill the cards as needed.

4. Bird Garden

If you get serious about birding, you might think about planting a bird garden. Find out abut which native plants in your area provide food or shelter for birds and add a few to your garden. Providing water through a birdbath or pond is also helpful as long as the water is kept clean and fresh. Check for more information in books, magazines and on the Internet for useful plants to grow in your region or community.

5. Fly like a Bird

Study birds in flight. Make a kite, decorate it like a bird and fly it on a windy day.

Finally, even if it is raining and nothing is happening outdoors, ask your child what it would be like to fly like a bird. Then pretend you are birds. Spread your wings and soar and swoop together.

For more information try:

Audobon

American Birding Association

Cornell Laboratory of Ornithology

Bird Studies Canada

For the Birds: The Life of Roger Tory Peterson by Peggy Thomas and illustrated by Laura Jacques

Hardcover: 48 pages
Publisher: Boyds Mills Press (October 1, 2011)
Language: English
ISBN-10: 1590787641
ISBN-13: 978-1590787649

And these books about birds for children:

Characteristics of Five Major Orders of Insects

Scientists who name insects have grouped them into about 30 different orders (the exact number is still under debate). However, five of the orders are the most common.

1. Beetles (Order Coleoptera) – Of all the more than one million species of insects, beetles are by far the most numerous. There are an estimated 350,000 to 400,000 different species of beetles!

Characteristics:
Adults with hardened front wings called called elytra. Hind wings are generally under the elytra and are membranous (sort of like plastic wrap).

Beetle larvae are grubs or worms with a distinct head.

One type of beetle larva is called a wireworm.

Beetles go through complete metamorphosis, which means they have four life stages:  egg, larva, pupa and adult.

See the life stages of a carpet beetle

2. Flies and mosquitoes (Order Diptera)

Characteristics:

The order name of this group means “two wings.” Unlike all other insects, adult flies have only two wings, rather than the more common number of four. (The second pair of wings have been reduced to a knob-like structure called a haltere.)

Flies also have complete metamorphosis. Most fly larvae lack a distinct head and are commonly called maggots.

3. Ants, bees and wasps (Order Hymenoptera)

Characteristics:

Most adult hymenoptera have four membranous wings, with the forewings larger than the hindwings, although it might be hard to tell in a resting insect because their wings are folded. Many bees, wasps and ants have a stinger, which they use to defend themselves or subdue prey. Bees and wasps, in particular, have black-and-yellow or black-and-red warning coloration.

Bees have robust bodies and are usually quite fuzzy.

Wasps are usually hairless and shiny.

Ants have antennae that bend in the middle, like an elbow.

Hymenoptera also have complete metamorphosis.

Ant larvae are shaped like a crochet hook. They have a head, but no legs. The smaller, yellowish ovals are the eggs. The beige sack towards the top right is a pupa within a cocoon.

Bee larvae also lack legs. The larvae are on the left, sitting on the bright yellow bee bread that they use for food. The four white objects on the center/right of the photograph are pupae. You can see some of the characteristics of the adults, like eyes and mouthparts, in the pupa.

4. Butterflies and Moths (Order Lepidoptera)

Butterflies and moths have four large wings, usually covered with flat scales

Butterflies are brightly colored and fly by day.

In general, moths (like this atlas moth) are more drab and fly at night.

Lepidoptera also undergo complete metamorphosis.

The larvae of butterflies and moths are called caterpillars.

See this post for photographs of the butterfly life cycle and more information.

5.    True bugs, as well as aphids and cicadas (Order Hemiptera)

Note:  The Order Hemiptera has undergone several revisions over the last few decades. For a long time there were two separate orders, the so-called true bugs were called hemiptera (meaning half-wing) and the aphids, cicadas and their relatives were called homoptera (meaning uniform winged). Then the Order Hemiptera was re-named Heteroptera. Finally, based on new evidence, the two orders have been combined into the Order Hemiptera. You will see names of the earlier orders in older texts.

Insects in the Order Hemiptera have sucking mouthparts that suck up fluids rather like a turkey baster.

The “true bugs”have interesting wings that are half leathery and half membranous. They also have a triangle-shaped piece in the middle of their back.

The membranous part of the wing is between the two raindrops in this photograph of a mesquite bug. Can you also see the triangle (just to the right of the center raindrop) and the sucking mouthparts?

In this milkweed bug the membranous portion of the wing is black, the leathery part is red. Can you see the triangle?

More about mesquite and squash bugs

The aphids, cicadas, leafhoppers and their relatives have wings that fold like a tent over the rear section or abdomen.

Underneath…

…you can see the mouthparts as a tube running between the bases of the legs.

Hemiptera have incomplete metamorphosis, which means they have three life stage:  egg, nymphs (that look mostly like an adult, but lack wings) and adults.

Here are stinkbug nymphs that just hatched from eggs.

This is a cicada nymph that lives most of its life under the soil.

Once again, in this view of the underside you can see the tube that it uses to suck fluids from tree roots.

(More about cicada nymphs)

So, there’s a quick overview of how to recognize some of the insects you might find in your yard.

Please feel free to leave any questions you may have in the comments.

About the Let’s Rock series books (which just came out in paperback this month):

1. Crystals by Richard Spilsbury and Louise Spilsbury explains what crystals are and how they form. The text includes mini-biographies of scientists who made important discoveries about crystals, and also includes hands-on activities, such as panning for crystals and growing your own crystals. It is packed with fascinating information.

Crystals are minerals that form in such a way that they reach their optimal shape, often having clearly defined sides, corners and edges. Crystals either grow from magma as it cools, or form when water containing loads of dissolved minerals slowly evaporates. The types that come from water may form at the surface or in caves deep underground. The book has an amazing photograph of gypsum crystals that formed in a cave that are so big they dwarf the men climbing on them (or you can see the photograph at National Geographic).

This is a calcite crystal my son got at the show. Calcite is an abundant mineral, probably the most common. It comes in a variety of colors and shapes. Some forms, such as the pink calcite here, may flouresce under UV light and phosphoresce (continues to glow) after it has been in the sun.

Crystal Activities:

A. Test to see if a crystal contains calcite

Gather:

• Crystals to test
• Acid, such as weak hydrochloric (strong vinegar may work)
• Dropper

You can tell if a crystal contains calcite by applying a few drops of an acid to the surface. Calcite will release carbon dioxide gas when treated with an acid, causing bubbles to form.

You can see the results in this video:

B. Open a geode

A geode is hollow roundish-shaped rock that often contains crystals. Obtain a geode from a rock shop, show or online and then crack it open. Note:  It’s always a good idea to wear eye protection when using hammers on rocks. Once you know what a geode looks like, keep you eyes open for naturally occurring ones.

(Growing with Science is not affiliated with the sponsor of this video.)

Edit: Or you can make a homemade geode.

Can you spot the garnet crystals in this rock?

More related activities:

Growing crystals here at Growing With Science

Grow Spikes of Crystals in the Sun at Exploratorium

2. Fossils by Richard Spilsbury and Louise Spilsbury discusses how fossils form, where they are found, and also gives instructions for making your own trace fossil using plaster. Budding geologists are going to love this fact-filled book.

As a biologist who studies living creatures, I find myself drawn to the fossils. I added a few to my collection yesterday, although I left behind a lovely trace fossil of spider footprints that was very cool!

Fossil Search Activity:

One of the booths at the Gem and Mineral show had a bin full of sand filled with small fossils, which is a fun searching activity for young children.

Gather:

• play sand
• large bin (or sandbox)
• small fossils (available online or at shows)
• colander or other tools for sifting sand (optional)
• hand lens or magnifying glass to examine the fossils closely

Place the sand in a bin or sandbox. Mix in sample fossils and let the children hunt for them. If your children are interested in dinosaurs, a few small plastic dinosaurs might be a fun addition, too.

Coral fossil

Shell fossil

Leaf fossil

Other posts with related activities:

Archelon and Other Fossils

Petrified Wood

3. Metamorphic Rocks by Chris Oxlade examines what metamorphic rocks are, how they form and some common types. The book contains instructions for making a model metamorphic rock out of clay and chocolate, as well as suggestions of books and websites where you can find out more.

Rocks are grouped into three types:  igneous, sedimentary and metamorphic. Metamorphic rocks are formed when the other two types, igneous or sedimentary, are exposed to extremes in temperature and/or pressure, or sometimes chemicals (especially in hydrothermal solutions). Typically this occurs deep within the earth.

Metamorphic rocks often have bands or layers of color where the mineral segregated during formation.

For example, see the bands in this sample of gneiss, a metamorphic rock:

One of our favorite demonstrations of how metamorphic rocks forms is a machine at Arizona State University that turns ordinary table salt and pepper into a hard rock. How? The secret is that the machine applies a good deal of pressure and the two substances meld together. It is very cool! We saw this at the Earth and Space Exploration Day.

Common metamorphic rocks include marble (from limestone), slate (from shale), quartzite (from sandstone), gneiss (often from granite) and schist. See page 17 in the book for hints for identifying each type.

Metamorphic Rock Activity:

Because metamorphic rock is often harder than other types of rocks, it is used for buildings and statues. Look for slate or marble floors, marble statues and headstones, slate tiles, quartzite blocks, counter tops etc. in public buildings near you.

Leave us a comment and let us know what you find.

Found out more about rocks and minerals

Crystals by Richard Spilsbury and Louise Spilsbury

Reading level: Ages 8 and up
Paperback: 32 pages
Publisher: Heinemann Raintree (January 1, 2011)
Language: English
ISBN-10: 1432946927
ISBN-13: 978-1432946920

Fossils by Richard Spilsbury and Louise Spilsbury

Reading level: Ages 8 and up
Paperback: 32 pages
Publisher: Heinemann Raintree (January 1, 2011)
Language: English
ISBN-10: 1432946900
ISBN-13: 978-1432946906

Metamorphic Rocks by Chris Oxlade

Reading level: Ages 8 and up
Paperback: 32 pages
Publisher: Heinemann Raintree (January 1, 2011)
Language: English
ISBN-10: 1432946889
ISBN-13: 978-1432946883

Books were provided by publisher for review purposes.

The science of organizing living things into groups is called classification. The Swedish botanist Linnaeus first proposed a system for grouping and naming organisms in the 1750′s. The system is hierarchical with the upper levels including those below it.

If you are older, you may have learned something in school like “King Philip Came Over From Greater Spain” to remember the hierarchy of groups. Recently scientists have added a higher level, the domain and removed the Kingdom Monera. Plants, fungi, animals and protists belong to the Domain Eucharya.

This video explains the domains:

The kingdoms contains many distinct groups called phyla. Each phylum is divided into a number of classes. The classes are further divided into orders, families, genera, and finally, species.

Here is the classification hierarchy of the honey bee:

Domain:  Eucharya
Kingdom Animalia
Phylum Arthropoda
Class Insecta
Order Hymenoptera
Family Apidae
Genus Apis
species mellifera
Common name: honey bee

Sometimes it can be difficult to visualize. If you are a visual person, try drawing some diagrams. Here’s one for insects.

Classification Activities for Children

Up until recently, classification was mostly based on the physical characteristics of the organisms.

1. Sorting is an important precursor for classification for very young children.

Gather:

• toys, balls, stuffed animals, etc.

For young children, sort by any feature you can think of.  You can sort by color, soft versus hard, shiny versus dull, by size. It’s a great way to learn opposites, colors, shapes, and vocabulary words, too. Have fun!

Later graduate to sorting various toy animals by classes. Although is is best to use realistic models or stuffed animals, you can use pictures as well.

Start with the vertebrates, the  fish, birds, reptiles, amphibians and mammals.What characteristics do fish have? (fins, scales, gills). How is a reptile, such as a snake, different from an amphibian, like a frog or salamander? (Dry skin, scales). How is a bird (with feathers and a beak) different from a bat (mammal)?

Once your child masters that level, add insects, spiders and other animals without backbones. You may also sort by other characteristics, such as carnivore (meat eater), herbivore (plant eater) or decomposer (eats dead plants). Make a box labeled with each characteristic for the child to place the objects in or simply make heaps on the floor.

What are some differences between the plant and the butterfly sitting on it?

2. Twenty questions

The guessing game “twenty questions” also can be modified to act like a classification key. Keys are used to identify living things and often utilize similar yes or no questions.

Have one person think of an object, preferably a living thing in this case. The point is for the others to ask yes or no questions, using narrowing the topic until someone can guess what the object is. The trick is that you are only allowed 20 questions.

Is it living or dead? Is it green? Does it have flowers? Does it have a backbone? Does it have feathers? Does it have scales? The characteristics that separate the kingdoms, phyla and classes can quickly narrow your focus to the correct group.

3. Build your own classification scheme.

Gather:

• bag
• paper clips
• small balls
• crayons
• chalk
• coins
• pencils

To explore ways to classify things, have your children build their own classification scheme using objects from around the house. Fill a bag beforehand with a mix of items similar to those suggested above. Ask the children to group the objects. What characteristics did they use? Would the balls and coins go together because they are both round, or did the coins go with the paper clips because they were metal? Name the groups, and then mix the items again to come up with another system.

One of the fun parts of classification is that there aren’t any right answers, just best guesses. Scientists rearrange the groups all the time as they gather more information.

4. Older children may want to investigate the use of DNA to group and identify living things.

Here’s a more advanced discussion of classification (also discusses cladistics, how classification is tied with evolution).

For more information try:

The next few days are also good times for viewing the Geminid meteor shower, with peak shower activity expected on December 13 and 14, 2011. Moonlight may interfere with viewing at certain times.

Tips:
1. Try to find a place that is dark for best viewing. Porch and street lights can fade out the meteors.
2. Remind your children there may be several minutes between sightings. In the wee hours of the morning it can be hard to be patient.
3. Blankets and lawn chairs that allow for viewing in a prone position help prevent neck strain and keep chilly viewers warm.

Once again, EarthSky has more detailed information.

This Tonight’s Sky video has even more objects to look for in the December 2011 skies.

If you do go out and observe some of these, I would love to hear what you see.

Way back when I started this blog, I purposely chose the title “Bug of the Week” for the long-running Wednesday feature because I knew I would want to include spiders, pill bugs, and other creepy crawlies, as well as insects.  A World of Bugs shows children the range of arthropods and other invertebrates that are often called “bugs.” It tells what their features are, how they grow, where they live, and how they move. It is filled with huge, full color photographs that are very attractive. On the last page, the book also has some suggestions for activities to do before and after reading the book.

Identification of insects and their relatives requires careful observation of their anatomy.

Insects are part of the phylum of animals called Arthropoda.  All arthropods have:

• supporting skeleton on the outside, called an exoskeleton
• bi-lateral symmetry, which means if you draw a line down the center the two sides will be symmetrical
• jointed appendages
• segmented bodies
• specialized appendages, like antennae

The major arthropod classes can be separated by comparing their number of body regions, legs, and antennae.

Activity 1. Compare various creatures to discover features using live arthropods to observe, pictures and rubber or plastic models to explore. Give the children free explore time at first, and then start to encourage them to observe the following features:

Arachnids are the spiders, ticks, mites, scorpions and their relatives

• Have 8 legs
• Have 2 body regions, the cephalothorax (literally head-thorax), and abdomen

Spiders have 6 or 8 eyes at the front of the cephalothorax. Spiders’ mouthparts are called chelicerae and typically end in a fang. Around the mouth are the pedipalps.

For detailed information about spider anatomy, see Invertebrate Anatomy Online, the Garden Spider.

Crustaceans

The Isopods, which are called pillbugs, roly-polies, or wood lice, and other common names, have:

• 12 legs
• 2 antennae (one pair small)

Pill bug activities for kids

Centipedes and millipedes

• Many legs per segment
• Many segments
• One pair of antennae

Millipedes have 2 pairs of legs per segment.

Centipedes have one pair of legs per segment. (Photograph from Wikimedia).

Insects have:

• Three body parts:  head, thorax and abdomen
• Six legs
• One pair antennae
• Many adults have wings, but not all

Next time we will discuss how to recognize the major groups of insects, the orders.

A World of Bugs by Charlotte Guillain

Reading level: Ages 4-8
Paperback: 24 pages
Publisher: Heinemann-Raintree (August 1, 2011)
ISBN-10: 1432955063
ISBN-13: 978-1432955069

Book was provided by publisher for review purposes.

Macaws are from Mexico, Central and South America. Their bright colors and inquisitive natures make them popular with humans.

Facts about Macaws:

• have colorful feathers
• can live 50 years or more
• have strong beaks for eating fruit and seeds
• males and females pair for life
• nest in tree cavities
• travel in flocks

Most macaws live in rain forests. A rain forest is a place with trees that gets a lot of rain. How much rain? Some rain forests get up to an inch of rain per day, or 365 inches per year! Rain forests are often found in warm, tropical regions, but there are also cooler rain forests. An example of a cooler climate rain forest occurs in the west coast of the state of Washington.

Tropical rain forests are home to an abundance of interesting, colorful, and unique birds, in addition to macaws:

• toucans
• hornbills (Africa and Asia)
• antbirds
• trogans and quetzals
• hummingbirds
• hoatzins (see video below)
• and many more

Activities:

1. Bird Beaks

Birds use their beaks for many of the same purposes that we humans use our hands. Birds eat with their beaks, build nests with them, and even groom themselves with them. Birds do not have teeth, but they do have tongues.

One of the first things you might notice about the macaws, toucans, hornbills and hummingbirds is how different their beaks are.

(Photograph of hyacinth macaw by Malcolm at Wikimedia)

The macaw’s beak is long and curved on top, coming to a hook at the end. The lower beak is short and stubby in comparison. It looks rather like a can opener.

Check out how these wild macaws use the pointed tip of their beak and their tongue to remove nut meats from nuts. Note: This video has numerous pop-up ads.

The toucan’s beak is so large that you might wonder how it flies. It turns out that the beak is very light. Toucans eat mostly fruit, although they also eat insects.

The hornbill’s beak is also very large. The structure on the top is called a “casque” and it is thought to be involved with calling (sound production). Larger hornbills have a diet similar that of the toucan. Smaller ones are omnivorous (they eat many things), or even carnivorous (eating only meat).

The hummingbird’s beak is long and slender like a needle. Known for drinking nectar from flowers, hummingbirds also eat small flying insects.

Eating like a Bird

1. Food

Gather:

• various small fruits like blueberries, raisins, nuts, 0-shaped cereals, gummy worms, and small crackers (check about food allergies beforehand and avoid foods with those ingredients). If you don’t want the children to snack on the food afterwards, choose inedible items like un-popped popcorn and packing peanuts.
• plates or dishes to present the food on
• variety of equipment to mimic bird beaks, such as tongs, toy pliers, toothpicks, chopsticks, tweezers or forceps, and straws
• paper cups or similar containers to act as the bird’s “crop” (where the food goes)
• timer (optional)

Depending on the number of children and the amount of food and equipment you have, you might want to form small groups.  Explain that the children are going to “eat like a bird.” Suggest that they try to put the different food items into their “crops” (cups) using the different tools, but not to use their fingers. Present each child/group with a plate holding an assortment of food items and allow them to freely explore the options. Do some tools work better than others? Brainstorm about what might be other challenging foods that birds might eat. How would you eat an oyster or a snail without hands? How would you eat a fish without dropping it? What other types of tools might be helpful?

Handling time:

Introduce the idea of “handling time,” that is the amount of time it takes to pick up, process and eat a particular food item. Using a single tool and a timer, see how many pieces of a particular food they can get into their crops (cups) in a short period of time, such as a minute. Try other kinds of food for the same length of time. Weigh the amount of each type of food that was gathered to discover which type was most efficient, or resulted in the most food consumed per minute. Graph the results.

Another way to perform this test might be to time how long it takes to pick up a particular number of one type of food item with different tools. For example, how long does it take to pick up 30 raisins with tweezers versus toothpicks?

Fluids:

Have you ever watched a bird drink? Notice how these chickens scoop up water and then tilt their heads back to let the water flow down their throats.

Drinking is also a challenge with a beak. Often the tongue helps. Scientists have recently discovered that hummingbirds have a tongue like a mop that they use to slurp up nectar. If you’ve ever visited a lorikeet exhibit, you might have seen the brush-like tongues they use to lap nectar.

Gather:

• straws
• spoons
• new toothbrush
• juice
• shallow bowls

Pour the juice into shallow bowl. Compare how easy it is to drink with a straw or spoon versus try to drink by collecting fluid in the bristles of a toothbrush.

2. Bird Craft

One thing that catches your eye about these tropical birds is their colorful feathers. Make a brightly colored bird.

Gather:

• craft pom poms (2 sizes, body and head)
• colorful feathers (available at craft stores)
• matching color chenille pieces, cut into short lengths for beaks
• sewing thread
• white or craft glue
• scissors

Chose 1 large pom pom for body and one smaller pom pom for the head for each bird. Take a few minutes to study the structure of the feathers. Find two similar feathers for wings and one for a tail. If the feathers are widely different sizes you can trim them with scissors. Choose a section of chenille to serve as a beak. Bend the chenille into a v-shape, if desired, or leave it long to serve as a hummingbird beak.

Glue the head and body together. Set aside to let dry or the head may slip when adding other elements. If you are doing a flock of birds, you can glue some while others are drying. Put a bit of glue on the hard tip of each feather (where it attached to the bird in real life) and insert it into the body on either side to form wings. Add glue to the hard tip of the tail feather and insert it on the opposite side from the head. Finally add some glue to the tip of the chenille and add to front of head, taking care not to move the wings and tail. Allow to dry.

Once dry, tie a length of thread around the body and hang up. You can create mobiles or flocks of birds or use them as puppets.

3. Bird homes and rainforest layers

The rainforest is divided into layers.

The emergent layer consists of the very tallest trees that push up through the canopy.

The canopy is the dense layer of treetops.

Under the canopy there may be little light. Wherever light passes through the canopy, young trees, shrubs and vines can grow. The forest floor is also teeming with life.

Birds like the hoatzin use the trees of the rainforest for homes and food.

Many birds live in the canopy layer of the rainforest, although some nest in the shrubs and vines of the understory. Ant birds follow army ant swarms running over the forest floor, catching insects and other arthropods chased up by the approaching ants.

Project:  Chose a rainforest bird that interests you and find out where it lives in the rainforest. Does it nest in trees in the canopy or shrubs in the understory? Where does it find food?

Prepare a short report and share what you have found out with others.

Macaws by Cecilia Pinto McCarthy

Reading level: Ages 4 and up
Library Binding: 24 pages
Publisher: Capstone Press (August 1, 2011)
Language: English
ISBN-10: 142966049X
ISBN-13: 978-1429660495

Rain Forest Life by Janine Scott

Reading level: Ages 4 and up
Paperback: 24 pages
Publisher: Capstone Press (August 1, 2011)
Language: English
ISBN-10: 1429671521
ISBN-13: 978-1429671521

Books were provided by publisher for review purposes.