These perturbations affect the tilt of the Earth's spin axis with respect to the Sun, and this causes changes in the heat received by the Earth from the Sun (changes in "insolation").
(These perturbations; affect; the tilt of the Earth's spin axis with respect to the Sun) (this; causes; changes in the heat) (the heat; received; by the Earth; from the Sun)
These perturbations this the heat
affect causes received
the tilt of the Earth's spin axis with respect to the Sun
changes in the heat
by the Earth from the Sun