Penning David A, Dartez Schuyler F, Moon Brad R
Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504-43602, USA
Department of Biology, University of Louisiana at Lafayette, Lafayette, LA 70504-43602, USA.
J Exp Biol. 2015 Nov;218(Pt 21):3364-7. doi: 10.1242/jeb.127449. Epub 2015 Sep 7.
Snakes are important predators that have radiated throughout many ecosystems, and constriction was important in their radiation. Constrictors immobilize and kill prey by using body loops to exert pressure on their prey. Despite its importance, little is known about constriction performance or its full effects on prey. We studied the scaling of constriction performance in two species of giant pythons (Python reticulatus and Python molurus bivittatus) and propose a new mechanism of prey death by constriction. In both species, peak constriction pressure increased significantly with snake diameter. These and other constrictors can exert pressures dramatically higher than their prey's blood pressure, suggesting that constriction can stop circulatory function and perhaps kill prey rapidly by over-pressurizing the brain and disrupting neural function. We propose the latter 'red-out effect' as another possible mechanism of prey death from constriction. These effects may be important to recognize and treat properly in rare cases when constrictors injure humans.
蛇是重要的食肉动物，在许多生态系统中广泛分布，而绞杀在它们的分布过程中起着重要作用。缢死性蛇类通过用身体环绕对猎物施加压力来使其无法动弹并杀死猎物。尽管绞杀很重要，但人们对其绞杀能力或对猎物的全面影响知之甚少。我们研究了两种巨型蟒蛇（网纹蟒和缅甸蟒）绞杀能力的缩放比例，并提出了一种新的绞杀致猎物死亡的机制。在这两个物种中，最大绞杀压力都随着蛇的直径显著增加。这些以及其他缢死性蛇类能够施加远高于其猎物血压的压力，这表明绞杀可以阻止循环功能，也许还能通过使脑部压力过高并扰乱神经功能来迅速杀死猎物。我们提出后一种“红视效应”是绞杀致猎物死亡另一种可能的机制。在缢死性蛇类伤害人类的罕见案例中，认识并正确处理这些影响可能很重要。
