Solved Evolutionary Relationships & Phylogenies Worksheet | Chegg.com - Free Printable

PART II: Building a Phylogeny without Knowing Species Names

#### Step 1: Understand the Character Table
The character table provides information about six species (A, B, C, D, E, F) and their traits:
- Long forelimbs for climbing
- Flat face
- Feathers
- Talons
- Hooves
- Endothermic
- Fur

Each trait is marked as either present (`1`) or absent (`0`).

#### Step 2: Analyze the Traits for Shared Characteristics
We need to group species based on shared derived traits (synapomorphies). Let's examine the traits:

| Species | Long forelimbs | Flat face | Feathers | Talons | Hooves | Endothermic | Fur |
|---------|----------------|-----------|----------|--------|---------|-------------|-----|
| A | 0 | 0 | 0 | 0 | 1 | 1 | 1 |
| B | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| C | 0 | 1 | 0 | 0 | 0 | 1 | 1 |
| D | 1 | 0 | 1 | 1 | 0 | 1 | 0 |
| E | 0 | 1 | 0 | 0 | 1 | 1 | 0 |
| F | 1 | 0 | 0 | 0 | 0 | 1 | 1 |

#### Step 3: Identify Groups Based on Traits
1. Species with Hooves: A, E
- Both A and E have hooves (`1`), while others do not.
- This suggests A and E are closely related.

2. Species with Feathers and Talons: D
- Only D has feathers (`1`) and talons (`1`).
- This indicates D is distinct from others in this regard.

3. Species with Long Forelimbs: D, F
- Both D and F have long forelimbs (`1`), suggesting they might be related.

4. Species with Fur: A, C, F
- A, C, and F all have fur (`1`), indicating they share this trait.

5. Species with Endothermy: All species except B
- All species except B are endothermic (`1`), which is a common trait but not very informative for grouping.

6. Species with Flat Face: C, E
- Both C and E have flat faces (`1`), suggesting they might be related.

#### Step 4: Construct the Phylogenetic Tree
Using the above observations, we can label the tree:

1. Node 1: All species split from a common ancestor.
2. Node 2: D splits off first due to unique traits (feathers and talons).
3. Node 3: C and E share a flat face, so they form a clade.
4. Node 4: A and E share hooves, so they form a clade.
5. Node 5: F shares long forelimbs with D but also has fur like A and C.
6. Node 6: B is the most distinct, lacking many derived traits.

#### Final Labeling of the Tree
- Node 1: Common ancestor of all species.
- Node 2: D splits off.
- Node 3: C and E form a clade.
- Node 4: A and E form a clade.
- Node 5: F splits off.
- Node 6: B is the most distinct.

The labeled tree would look like this:
```
1
/ \
/ \
/ \
2 B
/ \
/ \
3 F
/ \
/ \
C 4
/ \
/ \
A E
```

#### Answer for PART II
The labeled phylogenetic tree is:
```
A → Node 4
B → Node 6
C → Node 3
D → Node 2
E → Node 4
F → Node 5
```

---

PART III: Comparing Molecular Data

#### Step 1: Compare Amino Acid Sequences
We are given sequences for Species A, B, C, D, E, F, and G. We need to compare them pairwise to determine the number of differences.

#### Step 2: Pairwise Sequence Comparison
Let’s compare each pair of sequences:

1. Species A vs. Species B:
```
A: AVLLGMFASYTHKKSDCTRLGLFF
B: LPIFGFGISTYQKYTECDCLMLFW
```
- Differences: 17 positions

2. Species A vs. Species C:
```
A: AVLLGMFASYTHKKSDCTRLGLFF
C: AVLLGMFPCTTTKKSDEDCRLGLFF
```
- Differences: 5 positions

3. Species A vs. Species D:
```
A: AVLLGMFASYTHKKSDCTRLGLFF
D: AVLLGMFPSYTTHKSDSTRLGLFF
```
- Differences: 4 positions

4. Species A vs. Species E:
```
A: AVLLGMFASYTHKKSDCTRLGLFF
E: AVLLGMFPBYTHHKSDSTRLGLFF
```
- Differences: 4 positions

5. Species A vs. Species F:
```
A: AVLLGMFASYTHKKSDCTRLGLFF
F: AVLLGMFGSYTHHKSDCTCRLGLFF
```
- Differences: 5 positions

6. Species A vs. Species G:
```
A: AVLLGMFASYTHKKSDCTRLGLFF
G: LPIFGVGMSYTRKRSEDCDTLFLFW
```
- Differences: 18 positions

#### Step 3: Determine Closest and Most Distant Relatives
- Most Closely Related: Species A and D, and Species A and E (both have 4 differences).
- Most Distantly Related: Species A and G (18 differences).

#### Answer for PART III
1. Which two species are the most closely related, and how do you know?
- Species A and D, and Species A and E. They have the fewest differences (4 differences each).

2. Which two species are the most distantly related, and how do you know?
- Species A and G. They have the most differences (18 differences).

---

Final Answers

- PART II: The labeled phylogenetic tree is:
```
A → Node 4
B → Node 6
C → Node 3
D → Node 2
E → Node 4
F → Node 5
```

- PART III:
1. Species A and D, and Species A and E are the most closely related.
2. Species A and G are the most distantly related.

Boxed Final Answer:
\[
\boxed{
\text{PART II: } \text{A → Node 4, B → Node 6, C → Node 3, D → Node 2, E → Node 4, F → Node 5}
}
\]
\[
\boxed{
\text{PART III: } \text{1. Species A and D, and Species A and E; 2. Species A and G}
}
\]