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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 11:41 am Post subject: Eggs |
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Ok, so most of us know that turning eggs over will kill the animal inside. I have never really understood this untill the other day when i saw a crocodile program on TV. Basically after 16hrs the membrane in the egg attaches to the wall of the egg shell and creates a little pocket of air at the top so if the egg is turned the animal inside drowns.
What i want to know is does this 16 hour time frame apply to snakes aswell or is there another figure to work to? _________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 2:13 pm Post subject: |
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I hope nobody minds but i am going to use this thread to store info i find on the subject.
Quote: | the egg - or rather, since fishes lay eggs
of a sort, the amniotic egg without which of course we cannot begin to understand how the birds contrived
to emerge. It is one of the wonders of evolution. ... a minor miracle. .... Besides being smooth it is rigid
enough to protect its cargo while not being so hard that the chick will be unable to peck its way out. The
shell also is pervious to gases, so that the chick can breathe ... Suspended in the middle of the egg is the
yolk, supported by threads. You can rotate the shell of the egg twenty times without disturbing the yolk: the threads just wind up. The medium in which the yolk floats, the white or albumen, is remarkable too. ... I am
speaking of course of the bird's egg as it exists today. The reptilian egg, as it first emerged, was slightly
different. It contained the large yolk which served to nourish the developing embryo. It also contained two
sacs, the amnion, filled with liquid and containing the embryo, and the allantois, which receives the waste
products produced by the embryo while it is in the egg. It was however very different from the egg of fishes.
From the shell, constructed of crystals of hydroxyapatite and waxed over, to the altered chemistry, based on
fat rather than protein, the amniote egg was in a different class altogether, a stunning advance on the simple
blob of jelly that constituted the egg of frogs and fishes - a saltation if ever there was one. |
_________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 2:24 pm Post subject: |
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Figure 3. Development of extraembryonic membranes in an amniote egg (chick). In this early developmental stage, the yolk sac is expanding over the yolk. The amnion and chorion are expanding over the embryo and will eventually form the amniotic chamber. The allantois is expanding toward the chorion, with which it will form a respiratory membrane, in addition to storing metabolic wastes of the embryo. Redrawn from Campbell (1993). Copyright © 1996 Michel Laurin. _________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 2:32 pm Post subject: |
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Egg had protective membranes & porous shell enclosing the embryo
Has 4 specialized membranes --- amnion, yolk sac, allantois, & chorion
Amnion is a thin membrane surrounding a salty fluid in which the embryo "floats"
Yolk sac encloses the yolk or protein-rich food supply for embryo
Allantois stores nitrogenous wastes made by embryo until egg hatches
Chorion lines the inside of the shell & regulates oxygen & carbon dioxide exchange
Shell leathery & waterproof
Internal fertilization occurs in female before shell is formed _________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 2:39 pm Post subject: |
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Quote: | If amphibian eggs were laid on land, they would immediately dry out, killing the embryo. This cannot be explained in terms of evolution, which asserts that reptiles evolved gradually from amphibians. That is because, for life to have begun on land, the amphibian egg must have changed into an amniotic one within the lifespan of a single generation. How such a process could have occurred by means of natural selection and mutation-the mechanisms of evolution-is inexplicable. Biologist Michael Denton explains the details of the evolutionist impasse on this matter:
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_________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 2:44 pm Post subject: |
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Quote: | There are various factors that effect development of the egg during incubation. These include moisture, carbon dioxide levels, and temperature. In many reptiles this last factor is of dominant importance and the phenomenon is called `temperature dependent sex determination', or TSD. Essentially, a warmer temperature during the middle phase of incubation results in larger animals. If the animal is sexually dimorphic with larger females, then higher temperatures will generally result in females. This is the case with turtles where the female is larger, perhaps to aid in support the male on top of her shell in the mating. However, in the lizards, snake, tuatara and the crocodilians, where the male is bigger, higher incubation temperatures result in males. |
_________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Stevec Key Member
Joined: 04 Sep 2005 Posts: 346
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Posted: Sat Nov 05, 2005 10:28 pm Post subject: |
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Good question Dan.
To add, If I was to shake one of my eggs vigorously from side to side would this kill the embryo or merely mix up its patterning
Sorry Dan couldn`t resist |
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Dan Captivebred Communist
Joined: 08 Sep 2005 Posts: 1306
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Posted: Sat Nov 05, 2005 10:30 pm Post subject: |
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LOL, theres allways one - and trust it to be a printer to ask about mixing up pattern by shaking!!
Eitherway i'm not so interested in finding out so urgently now - i have 6 eggs at the minute and a long way to go by the looks of it.
I'll stick some pics up later on. _________________ TFA
The future is bright, the future is a net like pattern.................
I'm NOT an expert, so if you don't want to know my opinion don't ask!! |
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Scott W Site Admin
Joined: 15 Apr 2004 Posts: 13355 Location: London, England.
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Posted: Sun Nov 06, 2005 7:59 pm Post subject: Re: Eggs |
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Dan wrote: | Ok, so most of us know that turning eggs over will kill the animal inside. I have never really understood this untill the other day when i saw a crocodile program on TV. Basically after 16hrs the membrane in the egg attaches to the wall of the egg shell and creates a little pocket of air at the top so if the egg is turned the animal inside drowns.
What i want to know is does this 16 hour time frame apply to snakes aswell or is there another figure to work to? |
very interesting. I accidently knocked a tub of crested eggs yesterday, displacing most of them, 3 hatched today but I wonder if it will affect the younger eggs....I guess I'll just have to wait and see. _________________
Please DO NOT pm orders for reptiles, send email instead scott@captivebred.co.uk |
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