Talk:Constriction

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With all due respect to previous contributors; as an experienced keeper and breeder of (Australian) pythons for over forty years, I strongly disagree with the content of this article, but unfortunately have no citable material immediately at hand refuting the claims I take aversion to. Unless there is an unusually large discrepancy between the size of the snake and its prey, the mechanism causing death is solely asphyxiation caused by denying the prey any opportunity to breathe. While it is true that the prey will suffer some decrease in circulation, this effect is confined to the tissues nearest the skin (unless the snake, and only then in very rare instances, is wrapped around an animals neck!). The major blood vessels within the thorax are relatively far too large to suffer the decrease in blood flow necessary to cause cardiac arrest - to achieve this, the ribcage would need to be entirely crushed or flattened, and this does NOT happen. Please see also the python entry for a better description of constriction. Unless some credible references are provided in support of the cardiac arrest hypothesis, I shall consider replacing this with an entirely rewritten article when I next visit this page. Peter b 01:45, 27 March 2007 (UTC)

I'm re-writing the article, but FYI - the 'traditional' hypothesis is that snakes kill by suffocation, but the death of some prey items seems too fast for that, prompting the suggestion that the pressure of constriction causes cardiac arrest (Hardy, 1994. A re-evaluation of suffocation as the cause of death during constriction by snakes, Herpetological reviews). The proposed mechanism is that the pressure of constriction would lead to increased pressue in the main body cavity, in which the descending aorta and inferior vena cava are directly exposed. This would in turn transmit the pressure change directly to the heart, and if the prssure is greater than the max systolic pressure, the heart would stop (Note that blood flow does not need to reverse, but only for pressure in the body cavity to exceed what the heart can generate). [b]However[/b], this has not yet been verified. Brad Moon has made some compelling pressure measurements indicating that snakes can produce the pressures needed (Moon, 2000. The mechanics and muscular control of constriction in gopher snakes (Pituophis melanoleucus) and a king snake(Lampropeltis getula), Journal of Zoology), but hasn't proven that this is the cause of death.

In short, the cardiac arrest hypothesis should be seen as just that, a hypothesis currently being tested, but one with some interesting data so far. Mokele August 30, 2007 —Preceding unsigned comment added by Mokele (talk • contribs) 20:55, August 30, 2007 (UTC)

it's not only snake-related! see Asphyxia -- Melaen 13:07, 30 November 2005 (UTC)

Article says the sanke bites and holds on before applying constriction. Is this correct? RJFJR 01:27, 9 December 2005 (UTC)

The article says that snakes don't crush bones, but asphyxiate their prey, and then in the next sentence says they don't asphyxiate their prey, but make their hearts stop beating. Which is true? Also, the only informative section is on snake constriction, which is rather short - it could be moved into the boa page, and then this page could turn into strictly a disambiguation page like it looks like it wants to be? Kjl 15:43, 11 April 2006 (UTC)

[edit] Suffication-Is it true??

Discovery Communications made a documentary called Anatomy Of A Snakebite. They did an experiment about constriction and said that instead of sufficating the victim, the snake sueezes you until all your blood is in your head and your eyes may even want to pop out.