Why don't ducks freeze in the winter?

Photo by Derek Ramsey from Wikimedia.

Ducks have several traits that let them live in snowy weather, as  long as they can find food and water. 

Ducks have a special blood system that helps keep them warm on cold ground.  Warm blood leaving the duck's heart heats up cold blood coming from the duck's feet.  The paths for the warm blood and the cold blood come very close to each other.  This is called countercurrent blood flow.  It keeps the duck warm in the middle and the head, where it matters most. 

Ducks also have a lot of fat and feathers to keep them warm, just like a jacket.  Most of a duck's organs (like the heart and lungs) and muscles are under the fat and feathers.

Do all groundhogs live in tree stumps?

Photo from wikimedia.com.

No, most groundhogs live underground in tunnels they dig themselves.  The main entrance to the tunnel is usually a pile of dirt.  The tunnel often goes straight down for about two feet, and then turns into rooms for eating or sleeping.  The groundhog often digs more than one tunnel with more than one "door."  Groundhogs usually live where forests meet fields or yards.

If you dug a home underground, what rooms would you put in it?  How many doors would you dig?

What do crocodiles eat?

Crocodiles are not picky eaters!  They can eat almost any animal that drinks from the water where the crocodile is waiting.  This can include turtles, frogs, fish, birds, and more!  Big crocodiles can eat bigger animals like pigs, antelope, or horses.  Crocodiles in different parts of the world have different diets.  In Australia, crocodiles can eat wallabies, and in Africa crocodiles can eat zebras.  Sometimes bigger crocodiles will even eat smaller crocodiles!

Photo:  American Crocodile in Mexico by Tomás Castelazo, from Wikimedia.com.

Why do owl ears look like feathers?

Photo by Ian Britton at Freefoto.com.

Owls are birds and they have feathers that cover up their ears.  Some owls have feathers that even stand up and look just like ears!  The feathers on an owl's face make a circle called a facial disc that funnels even more sound to the owl's ears.  If you could see the owl without any feathers, you would see that its ears are not even!  One ear is higher than the other one.  This lets owls hear sounds coming from up high and down low easier. 

Owls have such great hearing that they can hear a mouse squeak from half a mile away!

Try holding your hand or a cup up around your ear.  You might be able to hear sounds louder, just the way an owl's facial disc helps it to hear sounds louder.

Can owls see in the dark?

Photo by Ian Britton at FreeFoto.com.

Yes, and so can people!  However, owls have large, sensitive eyes that can see little pieces of light 100 times better than people.  Outside, at night, it may seem completely dark to you, but an owl will see the tiniest bit of light and find things you cannot find.  Their great hearing also helps them find food in the dark. 

Did you know that owls may not see color?  What would the world look like if everything you saw was black, white, or gray?

Do earthworms have a head?

Photo by Michael Linnenbach on Wikimedia.com.

Yes!  Earthworms usually move head-first, but can also "crawl" backwards.  Inside the head is a small brain, a mouth, "light cells" that can tell the difference in light and dark, and a "nerve cord" that can tell if the worm is touched.  The head is on the end of the worm closest to the clitellum (the big patch near one end of the worm).  In this picture, the head is at the top. Also, the tail is often flatter and the head is usually a little more round.

Do earthworms dig?

Photo by Fir0002/Flagstaffotos at Wikimedia.

 Yes, though it is more like pushing their way through the dirt!  Earthworms have very little, tiny, hairs called setae all over their body.  They also have strong muscles that are shaped like circles and other strong muscles that go along their body.  When an earthworm is ready to dig, it sticks its setae (on its tail) out into the dirt.  The setae hold onto the dirt while the worm uses its muscles to stretch out as long as it can (and dig or push through the dirt!).  After it's stretched out, it sticks the setae on its head into the dirt to hold onto the dirt while it pulls its tail up close to the head.  Then it starts all over again!

If you're very quiet you might be able to hear the setae if you can convince a worm to crawl on a piece of paper.  If you have a magnifying glass, you might be able to see the setae, too.