Variations in Earth’s orbit

Changes in planet Earth's orbit seem to be considered seriously by science theories.

What were the causes of these orbital variations?

Have the occurred more recent than theory suggests? Perhaps even being witnessed and described by previous cultures all around the world?

solar system worlds changing orbit Nice modelWhat we showed is that even under natural conditions, it can become much drier than predicted by any of our models ... About halfway down they found salty layers some 300 feet thick, indicating a long-term drop below the sea's current level. This came in a period between ice ages, 115,000 to 130,000 years ago, when variations in Earth's orbit brought temperatures about 4 degrees hotter those of the 20th century equivalent to what is projected for the end of the 21st century.
Under the Dead Sea, warnings of dire drought | Science Daily

Combining the Nice Model, Milankovitch Cycles, Jumping Jupiters, the only thing that seems certain is planet Earth and other worlds in our solar system have not have long term steady orbits.

Variation in planets Earth's orbitalPeriodic changes in the "roundness" of Earth's orbit varies in cycles of 100,000 to 400,000 years. This affects how important "timing of the perihelion" is to the strength of the seasons. The growth and retreat of ice sheets are thought to be controlled by the combination of:

  • the tilt cycle which takes 41,000 years from onset to completion
  • the year precession cycle which is 26,000 years
  • the perhaps smaller effect of Earth's orbit eccentricities (non-circular and elliptical) cycle which can take 100,000 to 400,000 years for completion

What Turns Ice Ages On...and Off? | Texas A&M University

That orbital chaos and changes is the natural order. Not Immanuel Velikovsky's ideas of Worlds in Collision but Worlds in orbital Chaos?

Effects to life on Earth with orbital variations

What would happen to the various lifeforms and living environments on our globe if there was a more significant and quicker than usual variation in Earth's orbit?

Variations in Earth's orbit Milankovitch CyclesChanges in orbital eccentricity affect the Earth-sun distance. Currently, a difference of only 3 percent (5 million kilometers) exists between closest approach (perihelion), which occurs on or about January 3, and furthest departure (aphelion), which occurs on or about July 4. This difference in distance amounts to about a 6 percent increase in incoming solar radiation (insolation) from July to January. The shape of the Earth’s orbit changes from being elliptical (high eccentricity) to being nearly circular (low eccentricity) in a cycle that takes between 90,000 and 100,000 years. When the orbit is highly elliptical, the amount of insolation received at perihelion would be on the order of 20 to 30 percent greater than at aphelion, resulting in a substantially different climate from what we experience today.
Orbital Variations - Milankovitch cycles | NASA