Deletion? It is getting rid of them
The outward appearance of a trait is called a phenotype.
The phenotype of the organism can differ from the genotype(genetic makeup of a trait). This can happen if one half of the trait is dominant over the other half, creating the trait the dominant side 'codes' for.
A physical change could be the plantet and biosphere have a lot more O2 in the air so more organisms can survive and evolve
Relative dating arranges<span> geological events, the rocks they leave behind, in a sequence. </span>
