I was a bit concerned when I first saw my bipeds because I had so many very pushy brothers that I couldn't get near them and I wanted them to pick me. I got as close as I could and stared at them and then they picked me up and I knew they were mine.
Off topic for one second, when I got my african grey bird many years ago, he just looked at me and said: I love you. I melted. Animals do choose you in their own "way". It could be a certain look they give you, a certain tilt of the head, even a wink (JC winks at me).
When we went to look at Sassy's litter we knew we wanted a female and there was only 2 females in the litter. We got first choice..... one female was all white and was a hellion on wheels already at the age of 6 weeks. Sassy was all white with one little tan ear....I thought it gave her a little more character....and so we chose Sassy, picked her up 2wk. later. Gretchen was also 1 of two females and she was the largest....so I chose her. Maisy was one of many....there was at least two litters of varying ages ...... Maisy chose me, she kept following me around and showing more interest than the others.
My step son usually picks and it's all over from there. When I went to pick up my hound dog Jeb I went with intentions of getting a female, but once I seen him I knew he was the one for me. I didn't think twice about it then and still don't.
My 21 year old Heeler mix, my parents chose. I was only two when they got him but the day they got him at about 8 weeks old, he immediately stuck to me and is still my best friend! When I got my Collie, Alfie, four years ago, my aunt had taken me to a Collie breeder to look at their puppies when I fell in love with her Collie pup she had just gotten. They had a couple left, but the little nearly pure white one with the goofy ear caught my attention. The people said that they would probably be "stuck with this one" because nobody wanted him so of course that was the one I was going to take! And next came little Bodhi, our four month old Boxer pup! Rusty saw an add for him online and he looked so sad and weak and we had to go get him immediately. Then we saw him in the deplorable condition he was in and how terribly uneducated about dogs these people were and we just had to get him out of there. Love my boys.