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 تقريرانجليزي عن Rattlesnake
				
				
						
						
				
					
						
							[frame="9 80"]Rattlesnake
 
There are approximately thirty species of rattlesnake, 
with numerous subspecies. They receive their name for
 the rattle located at the end of their tails. The rattle is
 used as a warning device when threatened. The scientific
 name Crotalus derives from the Greek, κρόταλον,
 meaning "castanet". The name Sistrurus is the Latinized
 form of the Greek word for "tail rattler" (Σείστρουρος,
 Seistrouros) and shares its root with the ancient 
Egyptian musical instrument, the sistrum, a type of rattle.
Most rattlesnakes mate in the spring. All species give 
live birth, rather than laying eggs. The young are self-
sufficient from birth. Since they do not need their mother 
after birth, the mother does not remain with her young.
 However, at least one captive study has demonstrated
 that females and their neonates show some level of
 affinity for each other's company and will cross barriers
 to reunite if separated.
Contrary to popular myth, rattlesnakes are not deaf. In 
fact, the structure of their inner ears is very much like 
that of other reptiles. They do, however, lack external 
ears. Sound (whether from air or ground vibration) is
 transmitted to the snake's inner ear via bone and muscle.[/frame]
						
					 
					
				 
			 
			
			
		 
	 
		
	
 
		
		
		
	
 
	
	
	
	
	
	
	
	
	
	
	
	
		
		
			
				
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		- لا تستطيع إضافة مواضيع جديدة
 
		- لا تستطيع الرد على المواضيع
 
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		- لا تستطيع تعديل مشاركاتك
 
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