Page 66 - Amphibian

Did you know?

AMAZING FACTS

If a frog or toad is threatened by Bullfrogs generally sit around
a predator, it may inflate its lungs and wait for a potential meal
to swell up to twice its normal body size, to pass or land nearby before they
making itself difficult for a predator to lunge forward to catch it in their
swallow. If that doesn’t work, there is an wide-open mouths. While the bulk
equally effective backup plan: releasing of their diet consists of insects, spiders,
water from its bladder onto the predator. and other invertebrates, they will eat
just about anything they can stuff in Skin exudes
their mouths, including fish, snakes, toxic secrections
birds—and even entire mice!
Some amphibians have distinct
odors, which come from secretions
in the skin glands. The spotted salamander Got a salamander by the tail? Fire salamander
and the common toad, for example, are Think again. Many salamanders
described as smelling like vanilla. Mink will sacrifice their tails to get away from a
frogs smell of onion, and the fire-bellied predator. If a predator grabs the tail of one
toad gives of a whiff of garlic. of these amphibians, it will break off, Many salamanders exude toxic
and keep wriggling even afterward. This secretions from their skin to ward off
action distracts the predator, giving the predators, but the slimy salamander, found
Amphibians periodically shed their salamander time for a quick escape. A new in parts of Florida, is even more devious.
thin skins, because dead or worn tail usually grows back after a few weeks. When it feels threatened, it secretes a white,
skin interferes with its breathing. As often gluelike substance from its skin. This sticky
as once a week, a toad will put its head stuff is incredibly difficult to remove and
down and hunch its back to start the can even glue a predator’s jaws shut.
shedding process. The old skin splits down
the back and belly, and the toad pushes
and pulls at the skin with its legs to work Some frog calls are not what they
it forward and over the head. The lump seem. The bird-voiced tree frog
of old skin is promptly gobbled up, is a small frog that lives in the American
possibly for the nutrients it contains. Gulf Coast forests. Once it has climbed
into the trees, it calls with a series of
piping trills that sound exactly like a bird’s
When a frog swallows its prey, its call. The barking frog gives out a sharp,
enormous eyes bulge down against throaty croak that sounds like a dog’s
the back of its mouth. The eyeballs apply Engraving of Galvani’s experiment bark. The carpenter frog calls out in a
pressure to help push its dinner down into series of sharp, rapping notes that sound
its throat cavity. Frogs have played a vital role in like two carpenters hammering nails.
science. In the 18th century, Italian
anatomy professor Luigi Galvani used a
frog’s leg to show how a chemical reaction Amphibians change color using
could produce an electric current. When he special pigment cells called
touched the frog’s leg with two different chromatorphores. Inside these cells, grains
metals, an electrical charge went through of pigment shift to cause changes in color.
the muscles and nerves, and the legs The North American tree frog, for example,
twitched. This discovery eventually led is a vivid grassy green when resting on
to the invention of the electric battery. green leaves. When it hops to a brown
tree branch, the chromatophores shift
position and the frog changes to
The incredible North a well camouflaged brown.
American wood frog spends
the winter frozen solid, thawing
Frog swallowing its prey itself out again when the temperature
begins to rise. This frog belongs to a small
group of freeze-tolerant animals. As the
Like fish, amphibians that are temperature dips, the wood frog begins to
mainly aquatic do not have eyelids. hibernate. Its breathing and heartbeat slow
But terrestrial species need to protect their to a halt, and as much as two-thirds of the
eyes when they are underwater. These water in its body crystallizes into ice. The
amphibians have developed a see-through frog stays frozen for two or three months Frog has
changd
membrane that closes up from the bottom of each winter. color to
of each eye. The membrane lets the
match the
creature see when it is underwater, and plant.
also protects and moistens the eye. Some species of frogs have an
unusual way of coping if they eat
something that is poisonous to them—they
A group of birds is called a “flock,” regurgitate their entire stomach! Once the
but what do you call a group of stomach is outside its body, the frog wipes
frogs? A “chorus of frogs” is the name for it off with its legs to clean it, and then
a group of these amphibians. swallows it again. Tree frog

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