You can duplicate any layer in your Maya scene. 
	 
Note: A 
		
new render setup system is available that replaces legacy render layers and is the 
		
default system in Maya. This new approach simplifies the management of complex scenes for rendering and is now the recommended workflow. See 
		
Render setup in Maya for more information. 
	 
 
You can use this feature to create two layers that are similar with only minor differences. For example, use this feature if you want to have two identical layers, but with raytracing turned on for one layer and turned off for the other. With this feature, you do not need to create the two layers independently - you only need to create one layer and duplicate it. This eliminates the need to reassign objects, materials and attributes in order to create the second layer. 
	 
There are two options available with this feature: 
	 
- You can choose to copy both the objects and render layer properties (e.g. material overrides, render stats) to the new layer; or 
		
 
- You can choose to copy only the objects to the new layer and create new overrides for the duplicated layer. 
		
 
To duplicate an existing render layer
- From the 
		  Render Layer Editor, select the layer that you wish to copy. 
		
 
- Select 
		  Layers > Copy Layer > 
		  
 
		 
- Select one of the two 
		  Copy Layer mode. To create an exact duplication of the selected layer, including objects and render layer properties, select 
		  With Membership and Overrides. To carry over only objects, select 
		  With Membership.