What is small head syndrome???

[Nicole]

Fangs...

I am not familar with these tigers of which you speak, but I believe Darwin's theory explains this perfectly, that a beneficial mutation will be preserved and passed through generations, ie survival of the fittest...

This is very distinct from Lamarkism which would go along the lines of:
If one specemin from the mainland or island was moved to the other location it would develop the attributes of the specimins around it.
I just don't believe this is true.

Cheers,
Nic

[Steve&Jo]

Well I am definately learning alot of this forum. Thanks heaps everyone.

I am hoping to get these photos scanned tomorrow and should have them tomorrow night.

He is a Murray Darling, we took him up to the local reptile guy and even he said Jake was a really good specimen. He is growing at a fast rate!

The reason I asked about the small head syndrome, was because of a comment raised by someone else who saw Jake. And me being a newbie, had never heard of it and was curious.

[Hawkeye]

A little closer to home, humans have grown increasing their average height by about 30-40cm since the 1500's because of diet and health changes over time. The Japanese have exhibited similar growth rates in the last 100 years or so because of moving from a rice and fish diet to a higher energy western fatty diet. That is body adaptation.

I think with snakes it is a matter of the head is mainly bone and that has a slower growth rate than muscle/fat of the snakes body and hence you just get a disproportion for the period of time it takes for the head to catch up (and hence the ability for the head to catch up as Paul stated).

This is all theoretical however but seem to fit what happens.

In humans, the head is initially bigger at birth and the body catches up until the bones all fuse but if you give growth hormone the rate increases remarkably but still stops when the bones fuse (in early 20's).

Cheers Hawkeye

[popp]

I think quoting from books is fun cause you can find all sorts of things,but how a snake with a pinhead discussion turned into a history lesson i dont understand,well here is some quotes to think about & for those who hated history here is a bit about Jean-Baptiste lamarck and some theories; Lamarkism is an evolutionary theory, popular in the early 19th century, which suggested that aquired characteristics could be passed along genetically. Now largely debunked, this was the first theory of evolution proposed by science, and while genetic transferral of learned characteristics does not occur, aquired behavior can be passed on to the next generation.
Lamarckian inheritance: The inheritance of acquired characteristics. Until the late nineteenth century, it was generally believed that characteristics acquired by organisms in response to the conditions of life or as a result of their own habits could be inherited by their descendents, and both Lamarck and Darwin shared this general opinion. The possibility of this type of inheritance is denied on theoretical grounds by the current orthodoxy of genetics.
Interestingly modern advances in DNA sequencing and other aspects of molecular biology reveal that certain acquired structures of the immune system may be transferred from parent to child, defying commonly held evolutionary beliefs and recalling Lamarck assertion of the inheritence of acquired characteristics resulting from environmental factors. - see the book Lamarck's Signature, by Edward J. Steele, Robyn A. Lindley, and Robert V. Blanden (Perseus Books, 199.
Maybe nobody is really sure just exactly who is right.

[OzDAZ]

In regard to the Chappell? Island tiger snakes, i've seen a few doco's and read bits and pieces on the topic and my understanding or basically what I came away with was, that as the Island is isolated and food for the Tigers is virtually non existent except for the annual Mutton bird breeding migration to the Island.
The fact that the birds come to breed once a year, means in essence that the snakes only get one good feed a each year or at most a very restricted window of opportunity to bulk up.
One of the documentarys on the ABC I seen, said that a fair percentage of the Tiger snakes on the island die each season as, from the time they wake up after hybernation they only have a small store of fat stock (energy) left to go find that nest of fat little Mutton chicks before they are to weak to hunt due to the extended periods between feeds.
Keeping in mind the kind of enviromental conditions there living in, it makes sense to me that over a period of generations that only the strongest and best stock in their relatively small population (an island as apposed to the mainland) , that eventually only the largest and strongest of their gene pool would survive to procreate the next season.
A bigger snake can hold more body fat and therefore increase their chances of surviving the extreme breaks between feeding.
Also didn't someone mention power feeding involving Mutton bird oil, im not sure what the go is with these birds, weather it be high fat content or what, but thats basically the Chappell Island Tiger snakes main if not only food source.
In essence it seems to me the great size of the Island Tigers and the suggested larger venon yield is just a symptom due to having to adjust over time to a very different set of enviromental variables they needed to overcome to survive.
Weather this type of transition goes for all animals, Id doubt it, I tend to think the Tigers were lucky enough to have the goods to adapt where as other snakes ETC wouldn't have thrived or even survived in the same position

Sorry lost my train of though (Damn work got in the way of my day), but hope it makes some sense as it did when I was first thinking bout it.
Maybe ill edit if it reads to disjointed. :wink:

OZ :roll:
daryl@spitfire.com.au

[Fangs]

No you got it in a nutshell Oz,
As far as ism's go I wasnt trying to get into that but merely trying to point out that these particular snakes have adapted over a relatively short period of time.
As far as feeding time goes they feed only for a short period of time per year.ie:the mutton bird breeding season.they are also darker in colour apparently to catch more heat from the sun to speed up their metabolism so they can gorge on even more chicks.
cheers

[Steve&Jo]

Hey we finally got a couple of photos up in the gallery, they were taken when we first got him....hoping the recent ones turn out better when we develop them.

Im hoping one of you will tell me if he has got this "head problem".
I think he looks normal.. But of course I am biased....