amniota

Though all snakes have the same stripped-down, streamlined form, their hunting and killing techniques vary enormously. Some twine through the vegetation following the scent of birds’ nests, frogs’ eggs, or sleeping lizards. Others probe burrows on the forest floor, lurk next to flowers waiting to ambush hummingbirds, or dangle from branches pretending to be vines. Scent and vision are their most important senses, but pit vipers can also “see” the warmth of prey at night by using heat-seeking pits found on the snout. With no limbs, most snakes rely on their bite to kill. The bite of a coral snake also delivers a nerve agent that paralyzes a victim’s lungs and muscles. Vipers inject their prey with a potent venom that attacks the blood. Constrictors have no need for venom- they kill by asphyxiation, coiling around prey and tightening each time the victim exhales. The green vine snake (Oxybelis fulgidus), pictured above, can separate its jaw bones so that it can swallow prey wider than its own body. Backward-pointing fangs help ratchet the meal deep into the snake’s gullet. 

Text by Thomas Marent; Photo by rajeev

anonymous asked:

Do you have any references on reptile (particularly crocodilian) reproductive systems?

Hi, 

There are some nice illustration in: Remarks on the Cloaca and on the Copulatory Organs of the Amniota by H. Gadow, Philosophical Transactions of the Royal Society of London. B (1887-1895). 1887-01-01. 178:5–37

This book has a good coverage of the squamata:

Reproductive Biology and Phylogeny of Lizards and Tuatara. Edited by Justin L. Rheubert, Dustin S. Siegel, and Stanley E. Trauth CRC Press 2014

There are a few papers that might be interesting such as:

Evolution of External Genitalia: Insights from Reptilian Development by Gredler M.L. · Larkins C.E. · Leal F. · Lewis A.K. · Herrera A.M. · Perriton C.L. · Sanger T.J. · Cohn M.J. Sex Dev 2014;8:311-326

Morphology and Histochemistry of Juvenile Male American Alligator (Alligator mississippiensis) Phallus. Brandon C. Moore, Ketan Mathavan, and Louis J. Guillette Jr. The Anatomical RecordVolume 295, Issue 2, pages 328–337, February 2012