The Learning Zone

[Stefan-A]

Just came across this and decided to post the abstract, in case somebody gives a crap:

Experimental evidence that oral secretions of northwestern ring-necked snakes (Diadophis punctatus occidentalis) are toxic to their prey

Ryan P. O’Donnell, , Kevin Staniland, Robert T. Mason

Abstract

Ring-necked snakes (Diadophis punctatus) are suspected of being venomous because their Duvernoy’s gland secretions have high levels of phospholipase activity, which is characteristic of many viperid and elapid venoms, and because anecdotal reports of feeding behavior are consistent with the use of a venom. We tested the toxicity of northwestern ringnecked snake oral secretions to a natural prey species, northwestern garter snakes (Thamnophis ordinoides), by injecting 2–35 ml of oral secretions intraperitoneally. All doses were 100% lethal within 180 min. The dose significantly affected the time to loss of a righting response. Neither injection of saline nor denatured oral secretions resulted in loss of a righting response or any visible detrimental effects. We suggest that northwestern ring-necked snakes may have evolved venom to subdue larger prey items than the snake would otherwise be capable of taking.

[guidofatherof5]

I do. Thanks for posting it.
Would you send me the whole thing or a link. Thanks.

[Stefan-A]

I do. Thanks for posting it.
Would you send me the whole thing or a link. Thanks.

http://home.comcast.net/~tsirtalis/0...alevidence.pdf

[gregmonsta]

Interesting

[guidofatherof5]

I just read through it and found it a good read. I was going to say interesting but I didn't want to copy off of Greg. Since it was mentioned in the article I hope you don't mind my link.
http://www.anapsid.org/duvernoygland.html

[Stefan-A]

How and when did Old World rat snakes disperse into the New World?

Frank T. Burbrink, Robin Lawson

Abstract
To examine Holarctic snake dispersal, we inferred a phylogenetic tree from four mtDNA genes and one scnDNA gene for most species
of the Old World (OW) and New World (NW) colubrid group known as rat snakes. Ancestral area distributions are estimated for various
clades using divergence–vicariance analysis and maximum likelihood on trees produced using Bayesian inference. Dates of divergence for
the same clades are estimated using penalized likelihood with statistically crosschecked calibration references obtained from the Miocene
fossil record. With ancestral areas and associated dates estimated, various hypotheses concerning the age and environment associated
with the origin of rat snakes and the dispersal of NW taxa from OW ancestors were tested. Results suggest that the rat snakes originated in
tropical Asia in the late Eocene and subsequently dispersed to the Western and Eastern Palearctic by the early Oligocene. These analyses
also suggest that the monophyletic NW rat snakes (the Lampropeltini) diverged from OW rat snakes and dispersed through Beringia in
the late Oligocene/early Miocene when this land bridge was mostly composed of deciduous and coniferous forests.

[Stefan-A]

Maturity, mating and age-specific reproductive effort of the snake Natrix maura

A . HAILEY AND P.M.C. DAVIES

Department of Zoology, University of Nottingham, NG7 2RD, UK
(Accepted 19 March 1986)

So much for the 3-5 years mentioned in Reptiles and Amphibians of Europe (E. Nicholas Arnold & Denys W. Ovenden).

Who wants to guess why I looked up this article?

[prattypus]

Some young hanky panky going on?

[Stefan-A]

Some young hanky panky going on?

Yeah. I moved the discussion about that to my own thread.

[ConcinusMan]

So much for the 3-5 years mentioned in Reptiles and Amphibians of Europe (E. Nicholas Arnold & Denys W. Ovenden).

Who wants to guess why I looked up this article?

Yeah. I moved the discussion about that to my own thread.

That article might eXplain male garters' willingness to mate at any time of year as long as females are brumated and/or put out the attractant pheremone. Once or twice in a 15 year timespan my concinnus male tried it briefly with the female right after she shed. Usually that happened during a summer after brumation was skipped. No mating took place though. But these are animals and I'm sure many of them can adapt to climate change so that reproduction does happen one way or another. If they didn't find a way to make it happen... well, those snakes are long gone from this earth. That says alot about our own seXuality I think.