magma is the rock that is formed underground so when it comes on earth it'll cool down and form marble
Geographical variation refers to differences among populations in genetically based traits across the natural geographic range of a species. ... In the simplest case, we divide these factors into purely genetic versus environmental components to tease apart their relative contributions to observed phenotypic variation.
Biotic factors are anything in a ecosystem that is living, was living, or is going to live.
From this we can conclude that the biotic factors are remains of dead organisms and flora and fauna.
Temperature and minerals in the soil are abiotic, meaning they will never live.