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27 January 2012

Amazing Facts: The Wonderland of Frogs

Did You Know...?
  • All tadpoles develop into frogs, but all frogs do not develop from tadpoles.
  • Certain frogs swallow their eggs, then allow them to hatch into tadpoles and then mature into tiny frogs—in their mother's stomachs.
  • A frog's tongue is attached to the front of the mouth so that it can more quickly catch prey.
  • Some frogs can stay submerged under water for months. If left in a dry atmosphere, some species will die within 3 hours.
  • A Jamaican frog lays eggs in a cave and, after they hatch into frogletts, carries them out on her back to a friendlier environment.
  • A West Africa frog is covered with hair.
  • Most frogs eat only that which has a pulse, while 80% of the diet of the Indian green frog is leaves and flowers.
  • Some frogs can jump 20 times their own body length in one leap, over 50 feet for us humans. The longest known frog jump is about 33 feet.
  • Frog bones, like trees, form a new ring every year during hibernation
  • A painkiller with 200 times the power of morphine has been found in the skin of a frog.
  • Frogs cannot live in salt water.
  • Captive frogs have lived for as long as 20 years

Next time you are out in the country on a summer night, listen to nature's music all around you. Those high tenor voices coming from high up in the trees, those deep bass ones coming from way down the creek—you guessed it—it is the music of the wonderland of frogs.

What are frogs? Well, to describe them is a little tricky because there are so many varieties and they are so different.

Perhaps the best place to begin is with what frogs have in common. All are cold-blooded creatures that can live both in water and on land. Because their body temperature changes with their surroundings, they usually feel cold to us. They have two bulging eyes and a nose on top of their heads, external eardrums, no obvious neck, two front legs and two back legs, the latter being used for leaping. And they do not drink. How do they get moisture? All their intake is absorbed through the skin. Toads (a “land” variety of frogs) press against something moist to absorb water through their skin. They even have the ability to taste through the skin. And they have a body with insides very much like those of larger animals. Many high school students have dissected these creatures in biology classes where they saw intestines, liver, pancreas, lungs, spleen, etc.

I admit that this description is not very complete. But when our Creator decided to include frogs among earth's residents, He wanted them to be healthy and live in all kinds of places. So in many, many ways frogs differ, according to the region they inhabit. Of course, Pharaoh would not agree, but frogs in most places do provide a good service to their surroundings, helping to control insects, as well as being useful in medical research. Some are also used for food and are considered a delicacy, while others have poison in their skin.

What Does a Frog Look Like?

Of course, everyone knows what a frog looks like! If you have seen one frog, you have seen them all-right? Not exactly. Just look at the names of a few of the 2500 different species of known frogs, and you will have some idea of their diverse appearances. There is the Rocket frog, which actually resembles a rocket. Can you guess what the Horned frog, a native of South America, looks like? (It is as big as a large dinner plate and shaped like a mushroom with two little appendages on each side, has a couple of holes for breathing and two bulging eyes mounted over a huge smile.) Try to imagine what these look like: the Western Spotted frog, the Turtle frog, the Orange-crowned Toadlet (also a frog), the Clawed frog, the Wood frog, the Platypus frog, the White-lipped frog, the Goliath frog, and some 2500 others. Just how varied are they? They range in size all the way from less than half an inch to one foot!

Where Do Frogs Come From?

Some people used to think that frogs came from the sky during heavy rain. Before the rain started to pour down, there were no frogs to be seen. Then suddenly, they were everywhere. Being so sure they came from the sky, someone in England probably performed one of the first scientific tests: He put pans outside. It was soon discovered that they came from the ground, where they had hidden while waiting for the rain. Now they were hopping with joy.

Then came the theory that frogs evolved about 200 million years ago. Fossil remains have been found that were declared to be that old. Isn't it strange, though, if they came by evolution, that they still look like frogs after 200 million years?

Still others claim that they developed from tadpoles. This isn't exactly right either, as we will see later.

How Do Frogs Multiply?

Several species of frogs lay eggs—some lay as many as 4,000—in a mass of jelly (spawn) in water, and the eggs hatch into tiny tadpoles. Unlike frogs, the tadpoles have external gills for breathing under water (they do not have lungs,) and a tail for swimming. As they mature they begin to grow legs and develop lungs. Suddenly they quit eating for about four days. During this time, a remarkable change takes place: from tadpole to frog. Dr. Tyrone Hayes has commented on this amazing process: "In one tiny little egg, [are] two completely different animals." Is this evidence of evolution? No, the makings of the frog, as Dr. Hayes pointed out, are in the egg. An intelligent Designer placed everything in order many millions of years ago. Are they perhaps copies of something He created in the past on some other world?

What keeps the tadpoles from starving during the transition from tadpole to frog? Well, the Designer didn't overlook anything. He always cares for His creatures, small or large. You see, tadpoles don't just lose their tail, they absorb it. Nothing is lost except the gills, which disappear. Now little frogs, they hop out of the water.

But not all species of frogs lay eggs in water. One, the Foam Nest frog, lays eggs in a foam nest (in branches of a tree or bush). When the rains come, the nest dissolves and the eggs drop into the rain water, which is sufficient for the eggs to develop into frogs. (Just how did this frog figure out this unusual process, that they could build the nest and the rain would take care of the rest?)

Another group of frogs lay eggs in damp places instead of in water. These eggs do not hatch into tadpoles, but directly into baby frogs.

The Marsupial frog lays eggs in a brood patch on the mother's back, where they hatch and pop out as little frogs, ready to make their way in the world.

2 Poison-Arrow tadpoles on their mothers back. She will deposit them high up in a bromeliad plant "pool" to develop.

Do you think this is unusual? Read on.

Another Marsupial frog from the border between New South Wales and Queensland, Australia, lays her eggs in a patch of jelly right on the surface of the ground. The male keeps an eye on them until they hatch. The jelly then liquifies, allowing the tadpoles to swim freely-right into the males' "hip pockets" where they remain until they emerge as baby frogs.

As amazing as this is, it is a small wonder beside the incredible Gastric frog. Found in Queensland, Australia, this frog spends nearly all its time in water just relaxing. However, it is a powerful swimmer and is also capable of traveling long distances on land. The Gastric Brooding frogs, discovered in 1972 and 1984, had perhaps not been found earlier because of their small size and timid nature (males grow to about 1.2 inches, females to about 2.2 inches).

What is so strange about this frog? The female, after laying her eggs, swallows them—about 18-25 fertilized, cream-colored eggs. During the next 6 to 8 weeks, while the eggs develop into tadpoles, then into frogs, the female does not eat. The process switches off the production of hydrochloric acid in her stomach wall, shutting down the entire digestive process to prevent the mother from digesting the young. (Just think of the benefit for us humans if we could learn how to do this for patients with gastric ulcers.) The tadpoles do not feed either. As they mature, they become larger, filling most of the cavity inside the mother-so much so that she can't even take a deep breath.

Finally, after about 8 weeks, the mother opens her mouth wide and the youngsters are propelled into her mouth. They hop out, and go their way. Those that aren't ready for the outside world are just swallowed again until later. (How did the species survive while she was learning this remarkable process?)

Another type of Gastric Brooding frog rivals it closely. This frog also swallows its eggs, and in this frog no one knows how the young are prevented from being digested, because the gastric juices are not turned off. It is thought that the eggs may be covered with mucus, like the lining of the stomach wall, to protect them. These eggs hatch into tiny tadpoles, then into frogletts which mother frog expels at the appropriate time. Does this sound impossible? Perhaps you have been underestimating the ability of your Creator.* If He can make such creatures as these, we should have no doubt that He can fulfill what He has promised to His faithful children.

Music from Frogland

The sounds which frogs make are almost as varied as their means of reproducing. The pitch of the frogs' voice seems to be in direct proportion to his size: big frog, deep voice, tiny frog, high voice. For example, the Carpenter frog sounds similar to sawing a board with a handsaw, the Pig frog sounds like a grunting pig, and of course, the Bull frog sounds similar to a bull. (You can hear these and other sounds at www.naturesound.com/) Many of the frogs are identified by the sounds which they make (the Banjo frog, the Humming frog, the Moaning frog, the Quacking frog).

Home for Froggie

Frogs have something in common with just about every other living creature. Our Creator has designed them very specifically for the regions which they inhabit. And frogs inhabit just about every region on earth, the only exceptions being the regions of the Arctic and Antarctic. They are found in cold areas such as Alaska and Canada, in streams and lakes of the Deep South, rainforests, and even in the desert. How did the Creator equip these varying species to live in such varied places?

The answer to this question is more involved than the scope of this article, however a few observations will show us how little we know about our living companions on earth. We can only marvel at our Creator's handiwork.

Wood Frogs of the North

Let's visit the Wood frogs that live around the Alaskan ponds and forests. How do they survive?
When late July arrives, it's time to begin preparing to survive the winter. First, they disappear under the leaves in the forests to bed down for the winter. Even protected by the snow pack and bed of leaves, the temperature is believed to drop at least to 5° Fahrenheit. As the temperature drops and their eyeballs and brain begin to freeze, it seems that the cold sends a message to their tiny liver which begins to convert glycogen to glucose. The glucose floods their vital cells to resist drying (drying causes frostbite in humans). While the frog may appear dead, with eyes, and brain frozen rock solid, it isn't. When spring arrives it will thaw out and soon the melodies of frogland will be heard again.

How can evolution explain it? Any frog from the temperate or tropical zones would die under these frigid conditions. How did these frogs survive the Alaskan winters while they were "perfecting" their method of survival?

Frogs of the Desert

The desert frog's greatest need is that of every other desert animal: some special means of storing water. Some frogs that live in the Australian desert absorb so much water that the Aborigines catch them to drink their store of water during the dry season. The Australian water-holding frog forms a cocoon of its own shed skin that is so efficient at preventing dehydration that it can wait as long as seven years for water while it is burrowed underground.
The Wax frog can produce wax to cover itself, preventing dehydration during a dry season. (By what evolutionary process did it acquire the know-how and materials to make "wax"?)

Desert frogs, during intense heat, bury themselves in sand or clay and go into a state of torpor.

Tree Frogs

This group of frogs is found in North and South America, as well as Europe and Asia. Tree frogs are especially equipped for living in trees. They have little disks or pads on their fingers and adhesive pads on their toes, and a groove between the tip of the finger and the rest of the finger. Some tree frogs are even better provided for. They have a first finger that is opposed to the remainder (like our thumb) so they can grab onto branches. Their fingers and toes include special disks for sticking onto smooth surfaces.
Flying tree frogs, found in Central America and Southeast Asia, have webbed feet with fan-like structures that enable them to glide from tree to tree or to the ground without injury.

Of course, if a predator gets too close, the Tree frog can leap great distances, gliding to other trees or even sailing to the ground.

Self Defense

How do frogs defend themselves against predators? Some, like the Tomato frog, discharge a thick white substance which is irritating to animals and can produce allergic reactions in people.

Some frogs reflect the same amount of ultraviolet light as their immediate surroundings, making it very difficult to be spotted by predators such as snakes.

Others change their skin color to match the surroundings by expanding and contracting three layers of pigment cells in the skin. (How did Mr. Frog engineer the pigmenting of his skin in this most useful way?)

Many years ago hunters and warriors of South America discovered poisons in certain frog skins. They would kill the frog, then hold it over a fire, which caused the poison to drip out. Arrows dipped in the poison could be used for killing game or an enemy. This practice gave this variety of frog its name: Poison Arrow frog. Like other poisonous creatures and plants, the Poison Arrow frog is brightly colored. Some are blue, some green, some have bright yellow markings. This is code language to all who happen to come near, which means, "Leave me alone! I am not tasty at all!"
Of the poisonous frogs, the Golden Dart frog is most potent. It is said that one frog's skin contains enough poison to kill a thousand humans.

The tip of a dart is rubbed on this species of Poison-dart frog. The poison will be potent for more than a year.

The Frog Evolved?

Does it seem possible that with so much diversity among the frog family, all could have come about by evolution? Could each have designed itself for the exact habitat in which it lives?

For example, how can a frog swallow its eggs until they hatch and develop, without some Master Designer putting the right elements in place?

How long would a desert frog last if taken from the tropics and set free in a frigid Alaskan winter?

Each variety of frogs was specifically designed for its specific region. So masterful was this design that different species still exist, even after approximately 200 million years. What has changed with the process of evolution?

The frog is a rather delicate creature, especially in the larval state. Yet some frogs, those that lay the fewest eggs, are able to protect their young until they are ready to be on their own. Those that lay hundreds or thousands of eggs do so because only a few hatch and mature into frogs. The rest were designed to provide food for other small animals and fish. How did they survive and reproduce until they developed these peculiar features and instincts?

This is not to say that some frogs cannot live equally well in places which are not normal to them. But to introduce a different species to a totally different area can be devastating. Some years ago the cane toad,** was introduced into Australia to kill insects. It seemed like a great idea. These toads will eat almost anything that moves, including insects, small mammals, fish and other amphibians. And they reproduce very rapidly. Pharaoh thought he had a problem? His problem went away. Not so with the cane toads. There are parts of Australia that are literally crawling with them. To complicate matters, they are very poisonous! If animals, such as cats, dogs, birds, bite down on a cane toad, they die—no second chances. How does one figure this into evolution? The animals, since they die, can never learn to leave them alone!

No, frogs have not evolved. Our Master Designer created them and saw that they were placed in just the right environment to survive.

"There are signs for the believing nation in the creation of their (own) selves, and the creation of the animals He has scattered (across the world)." [Quran 45:4]


  • *This information was obtained from CSU (Charles Stewart University of Australia); ANCA (Department of the Environment and Heritage, biodiversity group, Australian Government); Monash University of Australia, and the University of Michigan, USA.
  • **Toads belong to the same family as frogs. The main difference is that toads generally have dry warty skin and spend more time on land than frogs. True frogs have smooth skin and can stay submerged without drowning.
  • This toad, "a living water bag" stores water during rain for time of drought.
  • Sources of Information used in this Article:
  • Charles Stuart University of Australia
  • Australian Nature Conservation Association 1996.
  • University of Michigan
  • ANCA (Department of the Environment and Heritage, biodiversity group, Australian Government)
  • Oregon Coast Aquarium; 
  • Irish Peatland Conservation Council
  • Alaska Science Forum
  • The Exploratorium of San Francisco
  • Lang Elliott, NatureSound Studio; 
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