ilankovitch cycles describe the collective effects of changes in the Earth's movements on its climate over thousands of years. The term is named for Serbian geophysicist and astronomer Milutin Milanković. In the 1920s, he hypothesized that variations in eccentricity, axial tilt, and precession of the Earth's orbit resulted in cyclical variation in the solar radiation reaching the Earth, and that this orbital forcing strongly influenced climatic patterns on Earth.
The fundamental niche is the entire set of conditions where the species can survive and reproduce. For a full range of conditions to occur the fundamental niche and however results in an inter species competition. It is also described as place were the organism feels free of interference.
