Copy+of+2WKST-Cladogram Who+Am+I Worksheet - Cladogram Worksheet ... - Free Printable

Cladogram Worksheet Solution and Explanation

#### Part 1: Complete the cladogram and answer the questions

The cladogram provided includes the following organisms:
- Shark
- Bony Fish
- Frog
- Crocodile
- Birds
- Rodents
- Primates

We need to fill in the traits (1-8) based on the characteristics of these organisms.

#### Traits from the box:
1. amniotic egg
2. bony skeleton
3. eggs with shell
4. feathers
5. four legs
6. hair
7. opposable thumb
8. vertebrae

#### Step-by-step solution for the cladogram:

1. Which organisms have amniotic eggs?
- Amniotic eggs are found in terrestrial vertebrates that lay eggs with a protective membrane. These include:
- Crocodile
- Birds
- Rodents
- Primates
- This trait is shared by all animals after the split from amphibians (Frog).
- Location: 3

2. Which organisms have amniotic eggs in shells?
- Eggs with shells are found in reptiles and birds.
- These include:
- Crocodile
- Birds
- This trait is shared by all animals after the split from amphibians but before mammals.
- Location: 4

3. A clade that includes frogs and crocodiles must also include what other animals?
- Frogs and crocodiles share a common ancestor that includes all tetrapods (four-legged vertebrates). Therefore, this clade must include:
- All animals after the split from fish (Bony Fish).

4. If all the organisms with four legs form a clade, which organisms make up the outgroup?
- Organisms with four legs include:
- Frog
- Crocodile
- Birds
- Rodents
- Primates
- The outgroup would be the organisms without four legs:
- Shark
- Bony Fish

5. Could a worm be part of this cladogram? Why or why not?
- Worms are invertebrates and do not have vertebrae or many of the traits listed (e.g., amniotic eggs, bony skeleton, etc.). They are not part of the vertebrate lineage represented in this cladogram.
- Answer: No, because worms are invertebrates and do not share the key traits of the vertebrates in this cladogram.

6. Birds most closely related to which group of animals?
- Birds are most closely related to crocodiles, as they share a common ancestor after the split from amphibians and before the divergence of mammals.
- Answer: Crocodiles

#### Completed Cladogram:
- 1: vertebrae
- 2: bony skeleton
- 3: amniotic egg
- 4: eggs with shell
- 5: feathers
- 6: four legs
- 7: hair
- 8: opposable thumb

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Part 2: Draw a cladogram using the information in the chart and answer the questions

#### Organisms and Traits:
| Org. / Trait | Eukaryotic Cells | Bipeda | Backbone | Legs | Hair |
|--------------|------------------|--------|----------|------|------|
| Human | ✓ | ✓ | ✓ | ✓ | ✓ |
| Tiger | ✓ | – | ✓ | ✓ | ✓ |
| Salamander | ✓ | – | ✓ | ✓ | – |
| Sponge | ✓ | – | – | – | – |
| Clown fish | ✓ | – | – | ✓ | – |

#### Step-by-step solution for the cladogram:

1. Which trait is most ancestral?
- Eukaryotic cells are present in all organisms listed. This is the most ancestral trait.
- Answer: Eukaryotic cells

2. Which organisms have hair?
- Hair is present in:
- Human
- Tiger
- Answer: Human, Tiger

3. What is a derived trait for humans when compared to tigers?
- Humans have bipedalism, which is not present in tigers.
- Answer: Bipedalism

4. According to the Cladogram, a sponge is more closely related to a ______ than a salamander.
- Sponges are simple multicellular organisms and are more closely related to clown fish (both lack backbones and legs) than to salamanders (which have backbones and legs).
- Answer: Clown fish

5. If a clade included all groups with a backbone, which organisms would make up the outgroup?
- Organisms with backbones include:
- Human
- Tiger
- Salamander
- The outgroup would be the organisms without backbones:
- Sponge
- Clown fish
- Answer: Sponge, Clown fish

#### Completed Cladogram:
- Cladogram structure:
- At the base: Eukaryotic cells
- Next level: Backbones
- Further splits: Legs, Hair, Bipedalism

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Final Answers:

#### Part 1:
1. amniotic egg (Location: 3)
2. eggs with shell (Location: 4)
3. All animals after the split from fish (Bony Fish)
4. Shark, Bony Fish
5. No, because worms are invertebrates and do not share the key traits of the vertebrates in this cladogram.
6. Crocodiles

#### Part 2:
7. Salamander
8. Eukaryotic cells
9. Human, Tiger
10. Bipedalism
11. Clown fish
12. Sponge, Clown fish

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Final Answer Box:

\boxed{
\begin{array}{l}
\text{Part 1:} \\
1. \text{amniotic egg (3)} \\
2. \text{eggs with shell (4)} \\
3. \text{All animals after the split from fish (Bony Fish)} \\
4. \text{Shark, Bony Fish} \\
5. \text{No, because worms are invertebrates and do not share the key traits of the vertebrates in this cladogram.} \\
6. \text{Crocodiles} \\
\\
\text{Part 2:} \\
7. \text{Salamander} \\
8. \text{Eukaryotic cells} \\
9. \text{Human, Tiger} \\
10. \text{Bipedalism} \\
11. \text{Clown fish} \\
12. \text{Sponge, Clown fish} \\
\end{array}
}