[TheLion]

This sounds like a croc. The only wobble I am aware of is what they call the "precession of the equinoxes" which the earth goes though about every 26 thousand years. The axis wobbles like a top that has slowed down.

[DBrow]

No crock. Look up Milinkovitch Cycles or the Milankovitch Orbital Forcing Theory, or Orbital Climate forcing.

You'll find loads of well documented data.

Holocene paleoclimate or paleocene paleoclimate may be useful search terms.

And of course my favorite, periodic extinction( which has been hotly debated for at least 20 years, that's when I got involved).