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Chapter 19 Zoology Ms. K. Cox http://allaboutfrogs.org/weird/weird.html. Life Cycle of a Frog . True Love? We will start with mating. .
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Chapter 19 Zoology Ms. K. Cox http://allaboutfrogs.org/weird/weird.html Life Cycle of a Frog
True Love? We will start with mating. • When Frogs mate, the male frog tends to clasp the female underneath in an embrace called amplexus. He literally climbs on her back, reaches his arms around her "waist", either just in front of the hind legs, just behind the front legs, or even around the head. Free PowerPoint Template from www.brainybetty.com
True Love? We will start with mating. • Amplexus can last several days! Usually, it occurs in the water, though some species, like the bufos on the right mate on land or even in trees!(photo courtesy of Emile Vandecasteele)While in some cases, complicated courting behavior occurs before mating, many species of frogs are known for attempting to mate with anything that moves which isn't small enough to eat! Free PowerPoint Template from www.brainybetty.com
Spawn (egg-mass) • While in the amplexus position, the male frog fertilizes the eggs as they are laid. Frogs tend to lay single eggs in masses, whereas toads usually lay eggs in long chains. Some frogs leave after this point, but others stick around to watch over the little ones. Some have very unusual ways of caring for their young. Free PowerPoint Template from www.brainybetty.com
What do they look like? Free PowerPoint Template from www.brainybetty.com
Egg • Frogs and Toads tend to lay many many eggs because there are many hazards between fertilization and full grown frogness! Those eggs that die tend to turn white or opaque. The lucky ones that actually manage to hatch still start out on a journey of many perils. Free PowerPoint Template from www.brainybetty.com
Example: • Some frogs, like the Coast foam-nest treefrog, actually mate in treebranches overlooking static ponds and streams. Their egg masses form large cocoon-like foamy masses. The foam sometimes cakes dry in the sun, protecting the inside moisture. When the rain comes along, after developement of 7 to 9 days, the foam drips down, dropping tiny tadpoles into the river or pond below. Free PowerPoint Template from www.brainybetty.com
Frog Life Cycle • 1. Amplexus • 2. Life starts right as the central yolk splits in two. It then divides into four, then eight, etc.- until it looks a bit like a raspberry inside a jello cup. • 3. Shortly after hatching, the tadpole still feeds on the remaining yolk, which is actually in its gut! The tadpole at this point consists of poorly developed gills, a mouth, and a tail. It's really fragile at this point. They usually will stick themselves to floating weeds or grasses in the water using little sticky organs between its' mouth and belly area. Free PowerPoint Template from www.brainybetty.com
4. Then, 7 to 10 days after the tadpole has hatched, it will begin to swim around and feed on algae.5. After about 4 weeks, the gills start getting grown over by skin, until they eventually disappear. The tadpoles get teeny tiny teeth which help them grate food turning it into soupy oxygenated particles. They have long coiled guts that help them digest as much nutrients from their meager diets as possible.By the fourth week, tadpoles can actually be fairly social creatures. Some even interact and school like fish! Free PowerPoint Template from www.brainybetty.com
6. After about 6 to 9 weeks, little tiny legs start to sprout. The head becomes more distinct and the body elongates. By now the diet may grow to include larger items like dead insects and even plants.The arms will begin to bulge where they will eventually pop out, elbow first.7. After about 9 weeks, the tadpole looks more like a teeny frog with a really long tail. It is now well on it's way to being almost fullgrown! Free PowerPoint Template from www.brainybetty.com
Young Frog, or Froglet • 8. By 12 weeks, the tadpole has only a teeny tail stub and looks like a miniature version of the adult frog. Soon, it will leave the water, only to return again to laymore eggs and start the process all over again! • Goes with or in between 1 and 2. Usually, about 6-21 days (average!) after being fertilized, the egg will hatch. Most eggs are found in calm or static waters, to prevent getting too rumbled about in infancy! Free PowerPoint Template from www.brainybetty.com
9. By between 12 to 16 weeks, depending on water and food supply, the frog has completed the full growth cycle. Some frogs that live in higher altitudes or in colder places might take a whole winter to go through the tadpole stage...others may have unique development stages that vary from your "traditional" tadpole-in-the-water type life cycle: some of these are described later in this tour.Now these frogs will start the whole process again...finding mates and creating new froggies. Free PowerPoint Template from www.brainybetty.com
My, What Big Ears you Have! • Frogs can hear using big round ears on the sides of their head called a tympanum. Tympanum means drum. The size and distance between the ears depends on the wavelength and frequency of a male frogs call. On some frogs, the ear is very hard to see! • Ever wonder how frogs that can get so LOUD manage not to hurt their own ears? Some frogs make so much noise that they can be heard for miles! How do they keep from blowing out their own eardrums?Well, actually, frogs have special ears that are connected to their lungs. When they hear noises, not only does the eardrum vibrate, but the lung does too! Scientists think that this special pressure system is what keeps frogs from hurting themselves with their noisy calls! Free PowerPoint Template from www.brainybetty.com
Tympanum Free PowerPoint Template from www.brainybetty.com
Different purposes for feet • Feet For Flying! • Feet For Digging • Feet For Swimming • Feet For Climbing Free PowerPoint Template from www.brainybetty.com
What are these feet for? Feet Free PowerPoint Template from www.brainybetty.com
What kind of feet are these? Free PowerPoint Template from www.brainybetty.com
What are these feet for? Free PowerPoint Template from www.brainybetty.com
What kind of feet are these? Free PowerPoint Template from www.brainybetty.com
I Only Have Eyes For You! • Frogs have variable kinds of eye types. The colored part of the eye is called the iris (EYE-riss). They can be brown, green, silver, red, bronze, and even gold. The pupils come in all kinds of shapes too! • (1) Round pupils: Some frogs have round pupils just like you and me. Newts and Salamanders also have round pupils. (2) Vertical pupils: Vertical pupils that look like a cats eye are really good for night vision and respond quickly to changes in light. (3) Horizontal-Shaped pupils: These are the more common pupil, good for normal day-vision. (4) Heart-Shaped pupils: I'm not sure if it serves any purpose, but it sure looks neat! Oriental fire-bellied Toads have this type of pupil. Some frogs have Triangular pupils, and some even have Star-Shaped pupils! Free PowerPoint Template from www.brainybetty.com
WHAT KIND OF EYES DO I HAVE? A C D B Free PowerPoint Template from www.brainybetty.com
WHAT KIND OF EYES DO I HAVE? A Round pupils C Horizontal-Shaped pupils D Heart-Shaped pupils B Vertical pupils Free PowerPoint Template from www.brainybetty.com
Lab Focus Today • Hibernation: The frogs that live in colder climates hibernate. Some dig holes or find cracks in logs or rock areas. Their heart beats and breathing slow down and their body temperature reaches close to the outside temperature. They have a lot of glucose in their bodies and it keeps them from freezing. Half-frozen frogs will thaw out and live. Some frogs hibernate under water. These don't breathe and get their oxygen from the water through their skin. (Cutaneous Respiration) Free PowerPoint Template from www.brainybetty.com
How to Tell if Your Tree Frog Is Male or Female • It can be hard to tell if your pet frog is male or female. • Do some measuring. Males are noticeably smaller than females in most species of frog. A typical male frog is one and one half to two and one quarter inches long from head to bottom. Females are two to three inches long. Free PowerPoint Template from www.brainybetty.com
How to Tell if Your Tree Frog Is Male or Female • Be a good listener. Males croak at night. This sounds like a duck quacking and sometimes a dog barking. Males will croak to the sound of vacuums, running water, loud noises, to attract females, and sometimes for no reason at all. Females, on the other hand, don't really make any noises. Free PowerPoint Template from www.brainybetty.com
How to Tell if Your Tree Frog Is Male or Female • Understand that if you still can't figure it out, you can ask an experienced breeder or a veterinarian. • Look at the throat. Most male frogs have a dark patch on their throat because as they croak it creates friction on the throat and darkens their throat. • Check the ear. The ear of the frog is near the brain. If its big, its a male but if it is small, then its a female. Free PowerPoint Template from www.brainybetty.com
Do Frogs Have Teeth? • Actually, yes! But not like in this silly picture! Free PowerPoint Template from www.brainybetty.com
Frog Teeth • Most frogs do in fact have teeth of a sort. They have a ridge of very small cone teeth around the upper edge of the jaw. These are called Maxillary Teeth.Frogs often also have what are called Vomerine Teethon the roof of their mouth. They don't have anything that could be called teeth on their lower jaw, so they usually swallow their food whole. The so-called "teeth" are mainly used to hold the prey and keep it in place till they can get a good grip on it and squash their eyeballs down to swallow their meal.Toads, however, do NOT have any teeth. Free PowerPoint Template from www.brainybetty.com
Super Skin • Frogs have very special skin! They don't just wear it, they drink and breathe through it. • Frogs don't usually swallow water like we do. Instead they absorb most of the moisture they need through their skin. Not only that, but frogs also rely on getting extra oxygen (in addition to what they get from their lungs) from the water by absorbing it through their skin. Because frogs get oxygen through their skin when it's moist, they need to take care of their skin or they might suffocate. Sometimes you'll find frogs that are slimy. This is because the frog skin secretes a mucus that helps keep it moist. Even with the slimy skin, these frogs need to stay near water. Toads on the other hand have tougher skin that doesn't dry out as fast, so they can live farther from water than most frogs. Free PowerPoint Template from www.brainybetty.com
In addition to jumping in water, frogs and toads can get moisture from dew, or they can burrow underground into moist soil. Frogs shed their skin regularly to keep it healthy. Some frogs shed their skin weekly, others as often as every day! This looks pretty yucky...they start to twist and turn and act like they have the hiccups. They do this to stretch themselves out of their old skin! Finally, the frog pulls the skin off over it's head, like a sweater, and then (this is gross) the frog EATS IT!!!! (EEEEEWWW!) Free PowerPoint Template from www.brainybetty.com
How Long Do Frogs Live? • Amazingly, this is the hardest question I've been asked about frogs! • It turns out that very little is known at all about the natural lifespan of frogs. Partially, this is because it's pretty hard to track a frog all its life! (I guess they havent figured out a good way to put little tiny collars around their necks!) • However,some records show that in captivity, many species of frogs and toads can live for surprisingly long times. They seem generally average somewhere between 4 and 15 years! • Recently I ran across a page where people were posting data about how long their species of frogs had lived in captivity. The longest lifespan entered was a European Common Toad (Bufo bufo ssp.) at 40 years!!!!! Free PowerPoint Template from www.brainybetty.com
Other species which live to ripe old ages include: • Giant Toad (Bufo marinus): ranging between 7 and 24 years • Green And Black Poison Dart Frog (Dendrobates auratus): ranging between 7 and 17 years • Oriental Fire-bellied Toad (Bombina orientalis): ranging between 11 and 14 years • Ornate Horned Frog (Ceratophrys ornata) ranging from 5 to 12 years Free PowerPoint Template from www.brainybetty.com
examples of albino frogs. • This weird looking guy was found in a garden pond in the UK.Species: unknown. Free PowerPoint Template from www.brainybetty.com
Pac-Man Frog. • Here is the albino version of the same species, the Pac-Man frog.(Photo from the Best Buy Commercial from 1997, featuring this website!) Free PowerPoint Template from www.brainybetty.com
Horned Frogs • Horned Frogs (Ceratophrys), like this Gastrotheca ceratophrys have a projecting flap, or "horn," of skin above each eye. Click on the image to see it full sized. Free PowerPoint Template from www.brainybetty.com
Frogs and Myth • Lots of different cultures have all kinds of interesting myths pertaining to Frogs. • Frogs and Weather Frogs have been associated with weather in a lot of ancient cultures. I guess this really makes a lot of sense if you consider that they tend to make a lot of noise before rain storms. • Some Australian aborigines and Native American groups believed that frogs were the bringers of rain. • In India, frogs were believed to personify thunder in the sky. Even the word for "frog" also meant "cloud" in Sanskrit! • In China, they see the "TOAD", not the "man" of the moon. The toad is also considered "one of the five poisons of yin." They say that eclipses happen when the "toad in the moon" tries to swallow the moon itself! Free PowerPoint Template from www.brainybetty.com
Frogs and Luck Sometimes, cultures associated frogs with good and bad fortune. • In Japan, frogs are the symbols of Good Luck. One myth I read dealt with the idea that bullfrogs are descended from a great ancestor who could suck all the mosquitoes out of a whole room in a single breath! • Some myths are less favoring to frogs and toads. Some folklorists* have claimed that "If the first frog that you see in the spring is sitting on dry ground, it signifies that during the same year you will shed as many tears as the frog would require to swim away in." Free PowerPoint Template from www.brainybetty.com
If, on the other hand, the first frog of spring jumps into the water, you'll experience misfortune all year! However, if the springs' first "hoptoad" come jumping in your direction, you will have many friends; if it jumps away from you, you will lose some. • Some less enlightened people associate frogs, and Toads in particular, as evil incarnations of demons or devils! • Frogs and Warts Some say that you get warts from touching frogs and toads. Free PowerPoint Template from www.brainybetty.com
You get warts from human viruses, not from frogs and toads!Frogs have slimy skin to stay moist when it is dry, and toads have bumpy skin to help camouflage them in their habitat. Some frogs and toads have paratoidal glands which secrete poisons as protection which can cause skin irritations and may be poisonous to some species of animals, but warts have nothing at all to do with the frogs themselves! • The French and the Frogs For some reason, the French have been given the nickname Frogs...There are many different theories about how this came to be... Free PowerPoint Template from www.brainybetty.com
The story I had always heard was that the nickname dates waaay back to sometime around the 18th century, when Paris was surrounded by many swamps...The French nobility that would visit Versailles apparently tended to refer to Parisians as frogs because of the swampy surroundings...and only later did the term get picked up to describe the French in general. • Another story I've heard was that American soldiers adopted the nickname for the French during the World War II because they ate frog legs and hid well when camouflaged. • I've also heard that a frog used to be on the French Flag, before the Fleurs de Lis was adopted when King Clovis took the throne.... Free PowerPoint Template from www.brainybetty.com
Batrachophobia- Fear of amphibians, such as frogs, newts, salamanders, etc.Ranidaphobia- Fear of frogs.Bufonophobia- Fear of toads. Free PowerPoint Template from www.brainybetty.com
End of Frog Section Free PowerPoint Template from www.brainybetty.com
Introduction • These are amphibians and are of the order Caudata in the scientific system of classification. The word "salamander" generally refers to any tailed amphibian lacking claws or ear openings. This means that newts are essentially salamanders. The definition of "newt" is a matter of great controversy and may vary from area to area or from country to country. Usually, the type of salamander known as a newt in many places is not as slimy as the majority of salamanders are, having rougher skin. Newts, unlike many other salamanders, may be semi-aquatic. Some people refer to salamanders that have a life stage known as the "eft" stage as newts. Again, however, such definitions may not hold true for everyone. For the purpose of this document, the word salamander will be used to indicate all types of salamanders including newts. Free PowerPoint Template from www.brainybetty.com
Housing • you should first determine what sort of habitat your animal is native to in the wild. Then, you should try to reconstruct this habitat as closely as possible. Most often this can be accomplished in a plastic or glass tank, as these are water impermeable. Free PowerPoint Template from www.brainybetty.com
Because salamanders can climb, aided with fluids or mucous secreted from their bodies, you should have a fitted lid for your enclosure. Salamanders often need such high levels of humidity, so a screen or mesh top may not be a good idea. Many people prefer to use a plastic lid with holes drilled into it. Free PowerPoint Template from www.brainybetty.com
Housing continued • the tank has been set up and running for at least a few days before your salamander arrives • Because salamanders are cold blooded and cannot produce their own heat, their temperature will essentially match that of their surroundings • Most salamanders, even terrestrial species, will require a high humidity. Generally this level is 50 percent or more. Free PowerPoint Template from www.brainybetty.com
Housing Continued • These animals absorb water through their skins rather than drinking it. Humidity may be increased and maintained in several ways. One way is to keep a bowl of water in the enclosure, although some people prefer to have a wet area of substrate rather than standing water. • Plants may also be used in the enclosure in order to help maintain humidity. These will allow shade to your animals in addition to collecting water droplets on their leaves. You may want to mist the enclosure several times a day as well Free PowerPoint Template from www.brainybetty.com
Housing Continued • Most salamanders will appreciate a hiding area in their enclosures. This can be created with leafy plants or with as simple an item as a cardboard box. This will provide it with a place to feel secure. Even aquatic salamanders will probably appreciate a floating plant that they can hide under. Many people like to place one hide box in each end of the enclosure. That way, the animal can thermoregulate without having to remain in the open. Free PowerPoint Template from www.brainybetty.com