a) Draw a phylogenetic tree based on characters 1-5 in the table below. Place hatch marks on the tree to indicate the origin of characters 1-6. b) Assume that tuna and dolphins are sister species and redraw the phylogenetic tree accordingly. Use hatch marks to indicate the origin of characters 1-6.c) How many evolutionary changes are required in each tree? Which tree is most parsimonious?Use figure 20.5 and 20.12 from the Campbell, Biology in focus.Can you pls explain this to me? Character1.Backbone2.HingedJaw3. FourLimbs4.Amnion5.6.MilkDorsal fin*Dolphins have 4limbs (2 fins and 2hind limb buds asembryos)Lancelet Lamprey Tuna Salamander(outgroup)000000100000110000111lo000Turtle111100Leopard111110Dolphin111*111 ▼Figure 20.5 Visualizing Phylogenetic RelationshipsA phylogenetic tree visually represents a hypothesis of how a group of organismsare related. This figure explores how the way a tree is drawn conveys information.Parts of a TreeThis tree shows how the fivegroups of organisms at the tipsof the branches, called taxa, arerelated. Each branch pointrepresents the common ancestorof the evolutionary lineagesdiverging from it.This branch pointrepresents the commonancestor of all the animalgroups shown in this tree.1. According to this tree, which groupor groups of organisms are mostclosely related to frogs?2. Label the part of the diagram thatrepresents the most recent commonancestor of frogs and humans.Alternative Forms of Tree DiagramsThese diagrams are referred to as "trees" because they use thevisual analogy of branches to represent evolutionary lineagesdiverging over time. In this text, trees are usually drawnhorizontally, as shown above, but the same tree can be drawn.vertically or diagonally without changing the relationshipsit conveys.3. How many sister taxa are shown inthese two trees? Identify them.4. Redraw the horizontal tree in Figure 20.2as a vertical tree and a diagonal tree.Rotating AroundBranch PointsRotationfRotating the branches ofa tree around a branchpoint does not changewhat they convey aboutevolutionary relation-ships. As a result, theorder in which taxaappear at the branch tipsis not significant. Whatmatters is the branchingpattern, which signifiesthe order in which thelineages have divergedfrom common ancestors.FishesFrogsLizardsChimpsHumansNote: The order of the taxadoes NOT represent asequence of evolution "leadingto" the last taxon shown (inthis tree, humans).FishesFrogsLizardsChimpsHumansVertical treeFishesFishesDiagonal tree.Instructors: Additional questions relatedto this Visualizing Figure can be assigned inMastering Biology.evolutionaryEach horizontal branch represents anlineage. The length of the branch is arbitraryunless the diagram specifies that branch lengthsrepresent information such as time or amount ofgenetic change (see Figure 20.13).Each position along a branch represents anancestor in the lineage leading to the taxonnamed at the tip.Chimps and humans are an example of sister taxagroups of organisms that share a common ancestorthat is not shared by any other group. Themembers of a sister group each other's closestrelatives.Frogs Lizards ChimpsIf you rotate thebranches of the treeat left around thethree blue points, theresult is the tree atright.Frogs Lizards Chimps HumansFrogsHumansChimpsHumansLizardsFishes5. Redraw the tree above, rotatingaround the green branch point.Identify the two closest relatives os ofhumans as shown in each of thethree trees. Explain your answer.

This phylogenetic tree is a hypothesis because they reflect the best model, or explanation, of biological relatedness based on all available evidence. As with any model or hypothesis, fresh data may give evidence for alternate linkages, leading to changes in the tree's postulated branching structure. It has the potential to be accepted or rejected.Answer a: The dorsal fin is not considered in characters 1-5. As a result, the phylogenic tree may be constructed as shown below- Explanation: Lancelet is an outgroup since she lacks any of the characters. All others have a backbone and are thus treated together based on the presence of backbone. Lamprey can then be separated based on the lack of a Hinged Jaw. Tuna can then be separated based on the absence of four limbs. Salamanders can then be classified as an outgroup because of the absence of amnion. Because both Lamprey and Turtles have milk, they are considered sister species.Answer b: Assuming tuna and dolphin are sister species and taking into account all six (1-6) traits, the phylogenic tree may be built as follows: Explanation: To treat Tuna and dolphins as sister species, the dorsal fin might be used to differentiate them.Answer c: The most parsimonious tree is the phylogenic tree (a). Explanation: In the case of (a), five evolutionary changes are required, but nine evolutionary changes are required in the case of (b).Conclusion: In both situations, a phylogenic tree is depicted. The phylogenic tree (a) is the most parsimonious since it requires just five evolutionary changes, whereas (b) requires 9 evolutionary changes.