Galapagos species are among those populations whose
members do not interbreed. The reasons that keep them from mating is that they
are separated due to differences in songs and beaks, individuals only recognize
and respond to songs of their own species. Therefore, geographic isolation and different
environments led to changes in traits that affected mating.
The oxygen cycle is closely linked to the carbon cycle and the water cycle (see hydrological cycle). ... Carbon dioxide enters the carbon cycle or is taken up by plants for photosynthesis. During photosynthesis oxygen is evolved by the chemical splitting of water and returned to the atmosphere