Quiz and worksheet on cladograms and phylogenetic trees, featuring questions about evolutionary relationships based on the provided diagrams.

Problem Analysis and Solution

The provided image contains three questions related to cladograms, phylogenetic trees, and evolutionary concepts. Let's solve each question step by step.

---

#### Question 1: According to the cladogram shown, which organisms are most closely related?

Cladogram:
```
┌───── Zygnonium
│
│ ┌── Exospermum
│ │
│ └── Belliolum
│ └── Bubbia
│
└────────── Pseudowintera
│
└── Drimys
│
└── Tasmania
│
└── Takhtajania
```

Solution:
- In a cladogram, the most closely related organisms are those that share the most recent common ancestor.
- Observing the cladogram:
- Belliolum and Bubbia share the most recent common ancestor (the node directly above them).
- All other pairs of organisms have more distant common ancestors.

Answer: Belliolum and Bubbia

---

#### Question 2: According to the phylogenetic tree, which organisms are the least related to each other evolutionarily?

Phylogenetic Tree:
```
┌──────────── Trilobita
│
Arthropoda ─────┴──────────── Chelicerata
│
│ ┌──────── Crustacea
│ │
Mandibulata ────┴───┴──────── Myriapoda
│
└──────── Insecta
```

Solution:
- In a phylogenetic tree, the least related organisms are those that share the most distant common ancestor.
- Observing the tree:
- Trilobita and Insecta are at the farthest ends of the tree and share the most distant common ancestor (at the root of Arthropoda).

Answer: Trilobita and Insecta

---

#### Question 3: Which term best describes a group of species without a known common ancestor?

Solution:
- The term that describes a group of species without a known common ancestor is polyphyletic.
- Polyphyletic groups are characterized by members that do not share a single common ancestor but instead have evolved independently.
- Other terms explained:
- Monophyletic: A group that includes all descendants of a common ancestor.
- Paraphyletic: A group that includes some but not all descendants of a common ancestor.
- Lateral: Not a standard term in evolutionary biology.
- Binomial: Refers to the two-part naming system for species (e.g., *Homo sapiens*), not a classification term.

Answer: Polyphyletic

---

Final Answers:

1. Belliolum and Bubbia
2. Trilobita and Insecta
3. Polyphyletic

Boxed Final Answer:
\[
\boxed{\text{Belliolum and Bubbia, Trilobita and Insecta, Polyphyletic}}
\]