Both – we all try and establish ourselves as the alpha (or as high up the ladder as we can be) while spending our energy taking care of and protecting others.

I am the alpha in my family while my wife tries to contest this to become the alpha (I can parallel park and that gives me the alpha spot but I fear I slip a little more everyday to her crazy feminine wilds), either way we are both working to provide for and protect our child/family.

Perhaps for someone without the “burden” of a family they are free to let their egoism grow. Someone with a greater family burden may be more likely to give up their dominant alpha position or at least be less likely to challenge the current alpha because they would rather spend their time being more selfless (like a grandma).