Friday, September 28, 2012

Frogs


Frogs, along with toads and newts and salamanders, are amphibians which means they go through rather dramatic stages of development.  They morph from gilled underwater dwelling creatures to terrestrial or semi terrestrial critters that breathe air.  Frogs and toads, unlike salamanders and newts, don't just grow legs but grow hopping cool hind legs.  Frogs and toads are similar.  Two notable differences are that toads don't need to keep their skin as moist as frogs do and are less expert jumpers.  For now, we will talk only of frogs.
 
 

 
 
 Let's begin at the beginning.
 
 
 
The male frog announces his availability to the female in song, amplified by his expandable throat sac.  The sound of his song varies by frog species ranging from a deep croak to a high pitched chirp.  The female responds by allowing the male to mount her.  She then lays up to 4,000 eggs.  The lovers part.
 
 
 
So begins the four stages of development.
 
 
 
 
 
The eggs, also know as spawn, float in the pond or sit in a damp nook near the water.  Many eggs are eaten by fish, bugs, turtles and birds.  After about a week, the eggs hatch into tadpoles.
 
Tadpoles have gills, they swim clumsily, and eat underwater plants.  At roughly four weeks of age, the tadpoles develop lungs and grow little teeth that allow them to eat larger plants.  At about 9 weeks, the tadpole grows hind legs and is now a froglet.
 
The froglet grows front legs and the tail slowly vanishes as it is absorbed by the froglet's body.  At about 3 months old, the froglet with only a stub of a tail and full fledged lungs, leaves the water.  Soon the last of the tail disappears and the froglet is a frog.
 
 

 
Some Frog Facts
 
- diet:  insects, rodents, birds, other frogs and snakes.  They don't drink water but absorb it through their skin 
 
- frog eyes are situated to enable vision from the front, back, and on both sides simultaneously
 
- predators:  cats, snakes, birds, frogs, lizards, rats
 
- approximately 2,800 species 
 
- frogs have been on the Earth for about 190 million years
 
- some frogs are camouflaged to hide from predators, such as the horned frog
 
- poisonous frogs are usually brightly colored to deter predators, such as the poison dart frog  
 
 
 
In cold climates the frog must hibernate. He burrows into the mud or muck in the bottom of a pond and stays there in a state of sleep whereby his body functions slow down to a minimum to conserve energy.  When the surrounding water warms in the spring, the frog awakens and his body returns to normal.  The first thing the frog usually wants to do at this point is to eat something.
 
Soon he is singing and the cycle begins anew.
 
 
 
 

4 comments:

  1. Their mating ritual sounds suspiciously like "Wham, bam, thank you, ma'am!"

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  2. Yup. One night standers, indeed. Opera singers to boot.

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  3. Imagine the human population would be smaller if we only dated guys who sang songs!

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  4. Not much in the way of romance... or of a parental role in the lives of the little critters...

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