Nesting Duck

The brown, egg-shaped midsection of this duck reflects one use of "spiral technology". A flat, wooden oval has been spiral-cut with a scroll saw. This allows the center to telescope, forming a nest. This is a Dave & Cristina contribution to the Museum of Duckological Artifacts.
Dave explained that a duck is a score of zero. My dad liked ducks and zeros.
Here's the zero poem he wrote:

Ode To A Nothing
The symbol's a circle, or an ellipse by designsIt's allowed no powers and carries no signs.Some call it a zero, a cipher named aughtOthers say it's a nothing, just simply a naught.
It lay undetected for centuries of timeTill along came an Arab, with naught on his mind."This thing looks useful, it stands for my worth"He thought as he gave the zero it's birth.
A zero plus zero remains zero they sayAnd zero remains zero with zero taken away.A zero times zero, still it's zero againBut zero divided by zero is a cardinal sin.
What good is this zero if it changes things naughtAnd you can never divide by this strange little aught?But a one's just a one without it, but thenTack on one little zero and you have numeral ten.
It a zero's a naught, it's a nothing we're taughtIf it's an aught, it's all things we've sought.Ought zero be a naught if an aught we have wrought?Or if it is aught, has it all gone for naught?
And if that's not enough, well son-of-a gunZero factorial turnes out to be one.Oh, little zero, you've got me confusedJust how many ways can you be used?
A zero's a nothing, this I contendTo make you a one, there's a rule I must bend.If I put you to the power of naughtYou become a one, again this we are taught.
If a zero's a nothing, there can be naught lessBut there is says the banker, take another guess.For a zero check balance is common to seeTo go beyond that, in the minus you'll be.
From the zero comes numerals both smaller and greaterTo the heights of the zenith, or down to the nadir.If you start with an aught and go to the endYou'll be back at naught, that's where you began.
So, hail to king zero who reigns till this dayIt's your rules we follow, if we're ever to play.You've a right to be proud, you haughty aught.But oh, what a problem, you naughty naught.