Evolution in action, in real time.

PLC1

PLC1

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Australian lizards on verge of evolutionary leap

Scientists observing a small group of Australian lizards very closely, believe they may be watching evolution happen right before their eyes.

A variety of Australian skink - like snake but with four tiny legs - is slowly starting abandon egg laying and beginning to give birth to live offspring like a mammal does.
Click to expand...

I saw this one on another forum, and decided to post it here as well. Quite interesting, isn't it? evolution in action!
 
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PLC1 said:
Australian lizards on verge of evolutionary leap



I saw this one on another forum, and decided to post it here as well. Quite interesting, isn't it? evolution in action!
Click to expand...

Really interesting story. I noticed this part though...

"Some researchers have suggested the transition from egg-laying to live-birth might not be as difficult as it initially appears.

Some skinks, they argue, simply retain the egg in the uterus for a longer period of time to protect it from colder external temperatures. The longer the egg is kept in the uterus, the thinner the shell becomes. When a skink is born live, all that remains of the shell is a thin membrane, which the mother helps the baby break open."


If this is true then they really are not giving birth, just holding the eggs in longer so it seems that way. Also it said the higher ones do this more than the lower ones, I wonder what kind of predator is lower or how much colder it is higher that might make them want to keep the eggs inside them longer.

Either way, its very cool

thanks for posting.
 
Pandora said:
Really interesting story. I noticed this part though...

"Some researchers have suggested the transition from egg-laying to live-birth might not be as difficult as it initially appears.

Some skinks, they argue, simply retain the egg in the uterus for a longer period of time to protect it from colder external temperatures. The longer the egg is kept in the uterus, the thinner the shell becomes. When a skink is born live, all that remains of the shell is a thin membrane, which the mother helps the baby break open."


If this is true then they really are not giving birth, just holding the eggs in longer so it seems that way. Also it said the higher ones do this more than the lower ones, I wonder what kind of predator is lower or how much colder it is higher that might make them want to keep the eggs inside them longer.

Either way, its very cool

thanks for posting.
Click to expand...

Yes, thats part of the Evolution...People where eggs to I am sure, at some stage in our Evolution...Its going to be small steps, not a bamn no egg live birth right away thing..

cool article...
 
Pandora said:
I would like to see any proof that humans used to lay eggs :)
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Visit any Gynecologist. He/She will tell you that humans produce eggs...they just attach to the uterine wall instead of being deposited outside the body. Also, note that many mammals give birth to offspring that are born in an egg sack (remnant of an "egg shell"), that is removed by the mother at birth.
Also, do you know that chickens have a navel by which an umbilical cord connects to a "placenta" that is attached to the inside of the egg shell?
There are many similarities that relate humans to other animal species.
It would be more convenient if women did lay eggs...we could find where they hide them and smash them before they hatched.
 
dahermit said:
Visit any Gynecologist. He/She will tell you that humans produce eggs...they just attach to the uterine wall instead of being deposited outside the body. Also, note that many mammals give birth to offspring that are born in an egg sack (remnant of an "egg shell"), that is removed by the mother at birth.
Also, do you know that chickens have a navel by which an umbilical cord connects to a "placenta" that is attached to the inside of the egg shell?
There are many similarities that relate humans to other animal species.
It would be more convenient if women did lay eggs...we could find where they hide them and smash them before they hatched.
Click to expand...

I know how babies are born :)

I would like to see some proof that humans used to squat and lay eggs in a nest before we evolved to how we currently do it.


cool about the chicken though, I didnt know that
 
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Pandora said:
I know how babies are born :)
Click to expand...
Not all do. I knew a girl (admittedly not bright), who went to the emergency room because she thought that she could feel something moving inside her. Turned out there was...she was well into a pregnancy.

Pandora said:
I would like to see some proof that humans used to squat and lay eggs in a nest before we evolved to how we currently do it.
Click to expand...
"Humans", never laid eggs. However, if you go way back to "pre-human" primitive life forms, you would find egg layers. However, if you really believe in Adam and Eve...

Pandora said:
cool about the chicken though, I didnt know that
Click to expand...
The "placenta" inside an egg shell encompasses the entire inside of the egg except for the "big" end of the egg wherein lies an air space. When the chick is about to hatch, it pokes it beak through the membrane separating the egg chamber from the air space, and chips away at its circumference (all the way around the air space which has enlarged during the incubation period), until it breaks away. It then struggles to exit the shell through that opening. Misguided, would-be helpers often make the mistake of trying to "help" the chick exit the egg and break away the shell which tears the membrane causing a few drops of blood to leak from it (remember, it is its placenta), and subsequently causing the chick to die from blood loss. It is quite a fascinating process.
 
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