Rattlesnake

Human Chimpanzee Sheep Rattlesnake Carp Garden snail Tobacco hornworm moth Baker s yeast (iso-1) Cauliflower... 

Furthermore, as shown in Figure 5.28, the number of amino acid differences between two cytochrome c sequences is proportional to the phylogenetic difference between the species from which they are derived. The cytochrome c in humans and in chimpanzees is identical human and another mammalian (sheep) cytochrome c differ at 10 residues. The human cytochrome c sequence has 14 variant residues from a reptile sequence (rattlesnake), 18 from a fish (carp), 29 from a mollusc (snail), 31 from an insect (moth), and more than 40 from yeast or higher plants (cauliflower). 

The venoms of poisonous snakes contain (among other things) a class of enzymes known as phospholipases, enzymes that cause the breakdown of phospholipids. For example, the venoms of the eastern diamondback rattlesnake (Crotalus adamanteus) and the Indian cobra Naja naja) both contain phospholipase Ag, which catalyzes the hydrolysis of fatty acids at the C-2 position of glyc-erophospholipids. 

Antivenins are used for passive, transient protection from the toxic effects of bites by spiders (black widow and similar spiders) and snakes (rattlesnakes, copperhead and cottonmouth, and coral). The most effective response is obtained when the drug is administered within 4 hours after exposure... 

A third group of myotoxic factors are very short polypeptides, devoid of hydrolytic activity. These toxins, found in the venom of a few species of North American rattlesnakes, cause a dilatation of sarcoplasmic reticulum and can cause severe muscle damage. 

Alving W.R. and Kardong K.V. (1996). The role of the vomeronasal organ in rattlesnake (Crotalus viridis oreganus) predatory behavior. Brain Behav Evol 48, 165-172. 

Chizar D. Walters A., Urbaniak J., Smith H., et al. (1999). Discrimination between envenomed and non-envenomed prey by W. Diamond-backed rattlesnakes (C. atrox). Copeia 3, 640-648. 

Duvall D. (1981). Western fence lizard (Sceloporus occidentalis) chemical signals, II a replication with naturally breeding adults and a test of the Cowles and Phelan hypothesis of rattlesnake olfaction. J Exp Zool 218, 351-361. 

Graves B.M. and Duvall D. (1985). Mouth — gaping and head — shaking by Prairie Rattlesnakes are associated with vomeronasal organ olfaction. Copeia, 496-497. 

Table 6.16 Rattlesnake Hill tholeiite (Philpotts, 1979) and its unmixes according to Ghiorso-Carmichael model (weight % = total iron as FeO).

Neonate garter snakes, Thamnophis sirtalis, and brown snakes distinguish conspecific from heterospecific odors (Burghardt 1977, 1983). Newborn timber rattlesnakes, Crotalus horridus, are able to follow conspecific odor trails (Brown and MacLean, 1983). Neonate water snakes are attracted to conspecific odor (Scudder et ah, 1980) and neonate prairie rattlesnakes, Crotalus viridis, to lipoids from the epidermis of adult conspecifics (Graves etal., 1987). 

Odor trails lead from the birthing rookeries of pregnant snakes to their ancestral winter dens. These trails probably help the neonates to find shelter (Graves et al., 1987). Socially naive neonate prairie rattlesnakes were tested for odor... 

Experience can further hone behaviors that are already present in naive animals. From 28 to 138 days of age, neonate rattlesnakes [Crotalus viridis and C. horridus) recognize and attack prey. They also show chemosensory searching and trailing. The initial trailing is Jerky and erratic, but after several feeding experiences becomes more methodical (Scudder etal., 1992). 

Two phenomena of reptilian prey searching are well investigated responses of various snakes to the odors of invertebrates, and rattlesnakes trailing of envenomated small mammals. 

Timber rattlesnakes, Crotalus horridus, are ambush hunters. They assume the ambush posture after smelling prey odors. In the laboratory, these snakes recoil the front part of their body into the ambush posture after flicking their tongues... 

The rattlesnake C. viridis searches for the particular odor it had experienced when striking the prey. In one experiment, snakes were induced to strike perfume-treated mice. Then they were exposed to perfumed, but non-envenomated, carcasses. The snakes preferred a carcass with the same odor as the originally struck mouse. In a second experiment, snakes preferred the carcasses of mice on the same diet as the ones they had struck. Thus rattlesnakes form a... 

In a number of species, the active predator odors originate on the dorsal skin. Neonate pygmy rattlesnakes, Sistrurus miliarius, and timber rattlesnakes, C. horridus, respond to dorsal skin chemicals of the ophiophagous king snakes and indigo snakes, Drymarchon corais, but not to those from ventral skin or skin... 

Rattlesnakes California king snake Lampropeltis getulus califomiae Skin rubbings Body bridging Bogert, 1941... 

Rattlesnakes King snake, human Air or skin extract, human breath Increased heart rate Cowles and Phelan, 1958... 

In black-tailed deer, Odocoikus hemionus columbianus, fecal odors of sympatric predators (coyote, C. latrans, and mountain lion, Fdis concolor) in vials next to food pellets inhibited feeding, while those of allopatric predators (lion, Fdis leo, snow leopard, Uncia uncia) do not, or very little (Miiller-Schwarze, 1972 Fig. 12.3). Note that mammals discriminate between the odors of sym- and allopatric predators, while fish and rattlesnakes do not (pp. 359 and 364). Free-ranging adult female wapiti, Cervus elaphus canadensis, respond to the odors of dog urine, and cougar and wolf feces (presented as water slurry) with increased heart rates. It was concluded that the main effect of predator odors may be for assessing the risk of predation (Chabot etal, 1996). 

Visual and olfactory stimuli contribute to anti-snake responses in mammals California ground squirrels, Spermophilus beecheyi, flag their tail and kick sand at a rattlesnake, C. viridis, more often than at a gopher snake, P. melanoleucus. The squirrels kicked sand at and approached a snake in a perforated transparent bag more frequently than one in an intact hag. Visual and chemical cues are important, but the latter seem to he the primary releasers (Henessy and Owings, 1979). 

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