 
					
				Oldest-known dome-headed dinosaur discovered sticking out of a cliff in Mongolia's Gobi Desert
The juvenile pachycephalosaurs, which predates the previous oldest dome-headed dinosaur by 15 million years, reveals more about how and when this unusual feature developed.
				 
				 
						
 
 
		 
					
				 
 
		 
					
				 
 
		 
					
				 
						
					 
					
				 
					
				 
					
				 
						
					 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		 
 
		