Final answer:
The relationship between different species can be supported by their similar DNA sequences and homologous structures, following the principle of maximum parsimony. These genetic and morphologic evidences are crucial in modern taxonomy for determining evolutionary relationships.
Step-by-step explanation:
A hypothesis that two organisms from different species are related to each other is best supported by evidence that their DNA sequences are highly homologous. This means that the genetic material of the two species has many similarities, indicating a close evolutionary relationship.
Additionally, scientists look at homologous structures, which are physical features that are similar due to evolutionary origin, rather than analogous structures, which may look similar but are not derived from a common ancestor. The concept of maximum parsimony also plays a role, suggesting that organisms with more homologous structures are more closely related evolutionarily. In modern taxonomy, scientists often refer to the "tree of life" to explain phylogeny or the evolutionary relationships among species. All branches on this tree originate from a single trunk, which represents the common ancestor of all life forms.