Category: Biology (Page 25 of 40)

Weekend Science Fun: Garter Snakes

Our science post this week was inspired by the new picture book Garter Snake at Willow Creek Lane by Janet Halfmann and illustrated by Anne Wertheim, part of the Smithsonian’s Backyard Book series. Starting out with her birth, the story follows the first season in Garter Snake’s life. ( See Wrapped In Foil for a full review.)

My earliest memory of garter snakes is from visits to my grandmother’s house. All my cousins and I knew that between the moist rocks around the old dug well was a sure place to find garter snakes. Everyone had a chance to catch one and handle it, carefully letting it go and washing our hands afterwards. None of us were afraid of garter snakes because of our experiences with them. This book brought back those fond memories.

Let’s find out more about garter snakes:

1. Garter snake facts

There are at least 20 species of garter snakes in North America, belonging to the Genus Thamnophis. Although supposedly named for the fact that the species with stripes resemble a garter (an old-fashioned band used to hold up stockings), some do not have any patterns, or have spots or checkered coloring instead of stripes. Individuals of one species, the common garter snake, can be different colors and patterns depending on where they are found.

This gopher snake has a strong checkered pattern.

Where do garter snakes live? Garter snakes are often found near sources of water. Some species are actually aquatic. They are found throughout North America.

Do garter snakes lay eggs? No, garter snakes and many other snakes give birth to live young.

Unlike other snakes, garter snakes are diurnal, which means they are out and about during the day. Many other snakes are nocturnal and hunt at night.

2. Outer covering

Reptiles are generally covered with bony plates or scales, which is one of their identifying characteristics.

Snakes’ bodies are covered with small plates called scales or scutes.

Have you ever looked closely at the scales of a snake? The scales on the back of a garter snake have ridges in the middle. They are called “keeled” scales. Snakes with keeled scales usually have a dull appearance overall.

Other snakes have smooth scales without the keels.

Snakes with smooth scales have a brighter, shiny appearance. Herpetologists (scientists who study reptiles) use the position of the different types of scales as one way to identify snakes.

Snakes have a special transparent scale over their eyes called a brille. It takes the place of an eyelid. Because of the brille, snakes can not close their eyes.

As a snake grows, it periodically sheds its outer skin. When the snake is about to shed, its brille becomes cloudy.

On this shed snake skin, you can see the bottom scales are larger and broader than the top scales. (I was actually taking a photograph of the ants that were recycling the skin.)

3. What do garter snakes eat?

Snakes are predators, feeding on other small animals. In the book, Garter Snake eats an earthworm. When in the water, garter snakes eat frogs, tadpoles and fish.

I can see this snake has eaten something recently. How can I tell?

4. Snake senses

One interesting aspect of snakes is that they have different senses than we do.

To smell, a snake doesn’t use its nose. Instead it has a bag-shaped organ called a Jacobson’s organ in its mouth to sense chemicals in the air. Ever seen a snake stick out its tongue? It is “smelling” the world around it.

Some snakes can sense infrared radiation through a pit organ or heat-sensing organ just below the eyes.

5. Make a snake craft

Gather:

  • One large “fuzzy” chenille (at least 20″ long) for each child
  • 10 + light-colored construction paper cut into 1 1/2″ wide strips by at least 12″ long for paper beads per child
  • assorted pieces of colored construction paper for head and features
  • markers or crayons
  • scissors
  • pencil (to form paper beads around)
  • white glue
  • photographs or illustrations of snakes

Process:  You might want to have the children make their paper beads in one session and assemble the snakes in another. For very young children, it would probably be best for an adult to pre-assemble the beads.

To make a paper bead, roll a rectangular strip of construction paper tightly around a pencil and then glue the free end down with white glue. Slide off the pencil and allow to dry. Make approximately 10 beads per snake.

While the beads are drying, start the snake. Have the children form a small loop at one end of the chenille to form the snake’s “head.” Have them cut out a construction paper head and tongue, if they would like. Decorate the head and glue it to the chenille loop.

Once the beads are dry, decorate with markers. Show the children photographs of actual snakes for inspiration. When completed, slide the beads onto the chenille behind the head. Bend up the tail a bit to prevent the beads from sliding off. Add finishing touches.

Now you have a snake in the grass.

For more information about garter snakes:

An informative video (may play ad the first time)

Look for Garter Snake at Willow Creek Lane (Smithsonian’s Backyard Book) (with easy to download e-book & audiobook).


Book provided by publisher for review purposes. Also, I am an affiliate for Amazon. If you click through the linked titles or ads and make a purchase, I will receive a small commission at no extra charge to you. Proceeds will be used to maintain this self-hosted blog.

Plants in Space Project

Tuesdays are plant days, so I’m going to sneak an extra post.

Do you remember the Spiders in Space Project? The same group is now conducting experiments with Plants in Space and you are welcome to join along, asking the question, “How do plants grow in space, without gravity?” The idea is to plant the same type of seeds here on earth at the same time as those in space and then look for differences in growth.

This project is for both classroom and homeschool students, as well as for informal science at home.

The experiments have already started. The first seeds were planted Tuesday, September 20, 2011 It is now completed, and the pictures and videos of the results are archived. Don’t worry, however, you can jump into the project with any of the next plantings:

  • Planting 2 will be Thursday, September 29, 2011
  • Planting 3 will be Friday, October 7, 2011
  • Planting 4 will be Monday, October 17, 2011

This video shows some of the results from the first planting.

Wow, dancing plants!

See the website in the link above for all the details, plus you can sign up and download a free instructor’s guide. The one for Spiders in Space was very good.

Weekend Science Fun: Explore a Tree

Our science fun this week is inspired by the book Seabird in the Forest:  Mystery of the Marbled Murrelet, written and illustrated by Joan Dunning (the link goes to a longer review).

This nonfiction picture book tells the incredible story of the marbled murrelet, a tiny seabird that searches deep in old forests to find a place to nest in a large tree. Once they build the nest, incubate the eggs and the eggs hatch, the parent murrelets fly all the way to the ocean to catch fish for their nestlings. They bring the fish back to the tree, a journey that may be as long as one hundred miles per trip.

The fact that murrelets nest in old-growth trees was only discovered recently, after all who would think of looking for a seabird nesting in a big tree?

Activity:  Investigate what sorts of animals live in a tree in your neighborhood.

Gather:

  • notebook
  • pencil
  • binoculars (if available)
  • camera to record observations (if available)
  • field guides to help you identify animals

Pick a tree in your yard, or nearby, to study. If you can, try to identify the tree. Go out each day for fifteen minutes. Slowly approach the tree looking for birds and squirrels first. Listen and look through your binoculars. Once you write down all the birds and squirrels that you see in the tree, then get closer and look for insects and spiders. Try to figure out what they are and what they are doing. Do this for one week. Or even better go out in the morning for ten minutes and the evening for ten minutes. Do you find different animals at different times of day?  After you are done, count how many animals use the tree.

Here is a list of some of the animals we found in our desert willow tree, Chilopsis linearis:

We chose the desert willow tree because it flowers most of the summer, supplying nectar and pollen for many visitors.

willowflower

desert-willow-flower1

Some animals that visit the flowers include,

carpenter bees like this one,

honey bees, flies,

green june beetles, hummingbirds,

verdins, and lesser goldfinches.

The lesser goldfinches might be taking nectar, but they also peck around the buds, perhaps looking for insects.

Although many birds perch in the branches to preen,

or to wipe their beaks like this house finch is doing, no birds have ever nested in the willow. Perhaps the foliage is too sparse to provide a good cover for a nest.

A few insects use the leaves for food.

We think these eggs hatched into…

this large caterpillar, which will become a Manduca rustica moth..

Several kinds of birds like the seeds.

mystery-seed-17

The trunk of the tree serves as a home for tiny ants that look for food (forage) around the flowers.

It is likely that the roots provide food for insects too, such as cicada grubs.

Of course, all the insects that feed on the willow may also serve as food for other animals. I suspect the verdins and the hummingbirds both feed on the small flies that are attracted to the flowers.

It seems like a whole community of animals depend on our desert willow for their livelihood.

How many animals do you think you will find on your tree?

If you try this project, we’d love to hear what you discover.

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