Kartikeya (also called Muruga, Skanda, Subrahmanya) is the son of Lord Shiva and Parvati. He is mostly worshiped in the southern part of India. He is also the commander-in-chief of the army of the devatas.He is also the God of war. He is mentioned in various puranas and known for defeating the demon Taraka. His mount is said to be a peacock. Generally deities have image of their mount(vaahan) on their flags. For example - Lord Vishnu is called as Garudadhwaja because he has Garuda on his flag. But Lord Kartikeya has a rooster on it.
My questions :
What is the story of emergence of Peacock and cock?
Why does Skanda have a rooster on the flag instead of a peacock?
What is the significance and symbolism of these birds and the rooster flag?