I have owned three dogs, L, R, and C. Here is their development in chronological order.
L is our first, male, neutered dog; born in 2000, we've had him since 2002 and he is still alive as of this posting. He shivers a lot, and was nervous coming out of his crate for weeks after we first got him. He loved to live under the bed. Eventually, he lives on top of the bed and buries himself, but he also makes his way down, eats, goes outside, and sometimes relaxes. He is very attached to my wife, going so far as to want to be in the shower with her; we used to have to lock the bathroom door to prevent wet dog every morning, until we got a shower with a sliding door. He seems to have wised up about these things and simply lays down on the rug and waits. L does not play with toys unless no one is looking. L would not eat unless no one was looking. L acts very submissive to my wife, flipping over for her and somewhat friendly (but also very vocal with barks) when she is home, but is a different, quiet dog when she is not around.
R is our second, male, neutered dog; born in 2001, we got him in 2003 or 2004 as a companion to L to help get L out of his shell. He passed away 3 years ago. R was a foodie and would eat until he burst if we let him (he had Cushing's Disease). R could be very aggressive in play, and loved to tug on rope and chase and catch frisbees. R would try to steal L's food (and our food). L would growl and chase R away from his food. Sometimes R didn't care what L thought, but other times he deferred to L. To get L to eat, instead of waiting for night time, we would bring R into the room, then L would gobble his food down. L and R played together a lot and relaxed against each other at times. It was rare, but occasionally L and R would fight, mostly over treats (which R would steal from L and hoard; we chalked that up to his hunger disease), and they each had nips in their ears from the other having bitten down. R was a larger sized dog than L. R was extremely attached to me and would follow my every command; he acted depressed when I was not around, but would still participate in play. He came when I called for him and tried to be with me whenever he could.
C is our third, female, spayed dog and is also alive at this time. We suspect she was born in 2008, and we got her in 2012 as a companion to L after R passed. She grooms L on the face constantly, and L licks her mouth at times and sniffs her. There has been a rare mounting attempts from L. They lay down next to each other and sleep together in a basket, not unlike how L and R would. She is the same size as R was. Now that L is older, he eats his food without prompting; something he learned during the his time with R. L will now try to steal C's food. If C sees L stealing her food, she rushes over, shoves L out of the way with a growl, and eats her food. She occasionally takes from L's bowl, but only when he isn't around. Like R, C is attached to me and waits at the door for me to come home; she dances like crazy when I arrive. She seems mopey when I am not home, in the same fashion that L is mopey when my wife is not home. She comes when I call for her and tries to be with me whenever she can.
Is (was) there an alpha dog here, and what could be used to identify the alpha? Is it L or C? Was R an alpha? Perhaps myself or my wife?