Which type of evidence is least likely to result in
changes to a phylogenetic tree?
dna sequencing
fossil record
discovery of new species
physical characteristics

Physical characteristics is least likely to result in changes to a phylogenetic tree. The reason is that the phylogenetic tree is related to the biological entities. The diagrammatic tree that represents the relationships so DNA sequencing affect this tree because if DNA sequence changes, then specie vary and may disturb relation flowchart.

Similarly, fossil record also is likely to result in changes to this tree. If there is discovery of new species then obviously it will change the phylogenetic tree but the physical characteristics are least likely to result in change to a phylogenetic characteristics. Phylogenetic tree is not a tree it is just like a tree which represents species and their relationships.

Physical characteristics.

Explanation:

The phylogenetic tree or evolutionary tree is used to explain the evolutionary relationship between the organism. Different characteristic and methods like maximum parsimony are used for the phylogenetic tree construction.

The different evidences like fossil record, new species discovery and DNA sequencing will provide the best evidence the phylogenetic tree. The physical characteristics can not be used to  construct the phylogentic tree because the physical characteristics of the organism changed over time according to the environment.

Thus, the correct answer is option (4).