What's the default delay amount for animation?

cocos2d-x JavaScript
#1

I want to know that in the case that I don’t specify any parameters into a function.
Just like this.

_punchJabAction = cc.Animate.create(_punchAnim);

#2

I found out that if I play the aniimation, but not set any delay, the animation won’ play properly (or we see it doesn’t play at all).

At least I guess some values must be there to make it work correctly.
For this result, I guess (by myself) that the default value if not supply to the parameter will be 0 or something negative. Anyone can confirm me?