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Timber Rattlesnake Essay Research Paper Crotalus horridusTheTimber

Timber Rattlesnake Essay, Research Paper

Crotalus horridus

The

Timber Rattlesnake

By

Arthur Ebbinger

Professor: Mr. Marquess

Biology: 1010

Date: 11 August 1999

The following is a brief description, as well as know characteristics commonly associated with the Crotalus horridus snake family. The Crotalus horridus is commonly referred to as the timber rattlesnake, or in more indigenous terms, the canebrake or banded rattlesnake. Its genus name is a translation from the Greek word krotalon, which means rattle. The species is a Latin word meaning “standing on end.” (Breen, 1974). Together they illustrate the rattler’s stalking posture. The Crotalus horridus is a member of the Animalia kingdom, the Chordata Phylum, the Reptilia Class, with a subclass from the Lepidosaura. The Crotalus horridus is also a member of the Viperidae Family.

The Crotalus horridus will vary in size from 35-75 inches, and alter in their color patterns. The northern variety sports a unique color combination of yellow-brown and/or gray to black, and of course each snake has its own distinctive crossbands. The southern variety is quite similar to that of the northern in its color patterns, however, the crossbands displayed are tan or reddish-brown.

The Crotalus horridus is a member of the pit viper (Viperidae) family as previously mentioned, which means heat is distinguished or sensed from apertures at the tip of the nostrils. The snakes are equipped with large recurved fangs, resting at the top of the mouth, and are specifically intended for liberal venom injection. The snakes are outfitted with a fascinating appendage that produces a buzzing sound when the tail is vibrated. Ironically, newborn snakes begin with only a single segment of tail. “This portion is commonly referred to as the button.” (Breen, 1974). The young adapt rather quickly with a second segment within the first ten days of life. A new segment is added for each shedding of skin.

The Crotalus horridus female usually mate in fall and give birth every two to three years, normally around the August – October time frame. She will produce anywhere from 5-17 young. “These newly born snakes will average between 10-13 inches in length.” (Campbell, 1997). Generally, the female is fully developed within 3-4 years and capable of reproduction at this time, if she falls within an interesting ratio. The fact is most female rattlesnakes have a 6:1 reproduction to non-reproduction ratio. The Crotalus horridus is considered a late developing, long-lived animal, and constrained by short periods of activity. These periods of activity coincide with regional seasonal variations.

The habitat of the Crotalus horridus extends from as far as New Hampshire and Vermont to the northern tip of Florida and west to central Texas and southeastern Minnesota. Depending upon the geographical location, the Crotalus horridus can be found in solitary areas along rocky highlands, wooded hillsides, swamps, and canebrake thickets. Throughout the winter months the snakes will hibernate, normally amongst other snakes sharing heat produced by their bodies. These snakes are more active during daylight hours in spring and fall, but change over to evening during the heated summer months.

The Crotalus horridus normal dietary intake includes small creatures, such as mice, rabbits, squirrels, and chipmunks. The snakes will wait motionless when prey approaches in order to ambush its unexpected meal. The snakes venom is used during the procurement of prey, and is quite adaptive in nature as it serves multiple purposes. The venom injected not only kills the prey, but assists in the digestive process as the meal is consumed. The venom is considered a deterrent of potential enemies. The snakes venom consists of complex proteins that quickly act upon the central nervous and circulatory systems. Interesting is the future possibilities of use from a medical standpoint. “Research indicates that the enzymes within the venom contain an anticoagulant that could save thousands of lives a year.” (Tyning, 1993). Breast cancer patients waiting for a cure may very well benefit from recent venom experiments, however only time will tell.

The main predator of the Crotalus horridus is mankind. However, there are other enemies lurking including: the king and other constricting snakes, owls, hawks, road runners, and coyotes. It is imperative to mention that the Crotalus horridus is a mild mannered snake that will avoid contact at all cost. Recall the significance of the tail. When placed in a precarious position, the snake will normally warn the victim before striking. If neither of the techniques work, the snake is basically left with no alternative but to protect itself. This snake is considered an endangered species in some regions because of the consistent harvesting and needless death of these animals.

Finally, there are basically three venomous snakes indigenous to our local area. The southern copperhead (Agkistrodon contortrix contortrix) is recognized by the copper colored head and dark brown hourglass patterns along the copper body. The tail will appear greenish or yellow. The southern copperhead can reach lengths of 30-50 inches. The second snake is the eastern cottonmouth (Agkistrodon piscivorous). This snake is customarily associated with every type of wetland. It has been know to roam overland in pursuit of food. The color patterns vary within this specie, but normally the adults are an off brown or olive with dark crossbands. The underside is yellow and brown. The third venomous snake indigenous to our area is the Timber rattlesnake (Crotalus horridus), which was extensively discussed in the previous pages.

Bibliography

References

Breen, John F. Encyclopedia of Reptiles and Amphibians. Massachuetts: T.F.H. Publications, 1974. 57-61.

Brown, Christopher W. Brimleyana: A study of variation in eastern timber rattlesnakes. New York: Brown and Co. 1986.

57-74.

Campbell, Jonathon A. “Venomous Snakes Book Review.”

American Zoologist. 37. 6 (1997): 650.

Ernst, Carl H. Venomous reptiles of North America. Washington : Smithsonian, 1992. 108-120.

Palmer, Thomas. “Rattlesnakes in a urban world.”

Natural History. 101. 11 (1998): 24.

Reinert, Howard. “Reptiles: Reproduction effects.”

Evolution. 52. 4 (1998): 1236.

Tyning, Thomas F. “Discover: Breakthrough in Science.”

Technology and Medicine. 14. 4 (1993): 12.

Wehner, Karey. “Snakes and Slithery Creatures.”

School Library Journal. 45. (1999): 31-34.

Weidensaul, Scott. “The Belled Viper.” Smithsonian Magazine. 28 (1997): 98-110.




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