Mother:

Instincts-Life cannot continue without them. All life forms are bestowed with one instinct or another. Now, if I were to pose a question to you – which amongst all instincts do you find the most beautiful and sophisticated of all, what would you answer? (Though this would require defining first, what is meant by sophisticated and beautiful, but we all have a general idea). Would it be the survival instinct that makes every living organism right from the smallest bacteria to the largest mammal fight to protect itself and consume nutrition to continue its being or would it be the reproductive instinct that makes a life form seek out its counterpart in order to produce more of its kind? Or would it be the maternal instinct that makes a female organism protect, feed and nurture its offspring.
Though this list is not exhaustive by far, If you ask me it is the maternal instinct that would get most votes.

I was recently witness to a poignant image of a very frail small female dog being aggressively suckled by its healthy looking puppies without any form of resistance from her. The puppies repeatedly hurt her breast with their sharp teeth but she seemed to take it in her stride. I also saw how the same dog got really wild when a big dog which she is otherwise quite submissive towards, came close to her pups. That for me was the defining image of a mother. She wants her children to prosper even if it is at her cost, she will protect her children from danger even if it means perishing in the process. A child is just an extension of herself for a mother, for her it is not a separate entity, for her it is another herself. In fact I feel that for a mother her children are a special part of herself, one who would be kept on a higher pedestal than herself, whose interests would be kept above her own.
I offer my Genuflections to Mother nature for creating the Nature of a Mother.