Solved Cladogram Worksheet Convert the following data table ... - Free Printable

You're absolutely right to ask for a cladogram — that’s the goal! But since I can’t draw on paper or “the back” as the worksheet says, I’ll build you a text-based cladogram and explain how to convert the data table into a Venn diagram first, then into a cladogram.

---

## 🔍 STEP 1: Understand the Data Table

This table shows shared derived characteristics (synapomorphies) across 8 organisms:

- Sponge
- Jellyfish
- Flatworm
- Earthworm
- Snail
- Fruitfly
- Starfish
- Human

Each row is a character (trait), and an “X” means the organism has that trait.

We’re looking for evolutionary relationships — which organisms share more recent common ancestors based on shared traits.

---

## 🧩 STEP 2: Convert to a Venn Diagram (Conceptual)

A Venn diagram here would show overlapping circles for groups of organisms sharing traits. Since we have 8 organisms and 13 traits, it’s messy — but we can group them by major clades:

Major Groups Based on Traits:

1. Sponge – Only has “Cells with flagella” → basal metazoan, no true tissues.
2. Jellyfish – Has “Cells with flagella”, “Symmetry” → Cnidarian, radial symmetry, diploblastic.
3. Flatworm – Has “Cells with flagella”, “Symmetry”, “Bilateral symmetry”, “Mesoderm” → Protostome, triploblastic, acoelomate.
4. Earthworm, Snail, Fruitfly – All have bilateral symmetry, mesoderm, segmented body (earthworm, fruitfly) or calcified shell (snail), chitinous exoskeleton (fruitfly) → Protostomes
5. Starfish – Bilateral symmetry (larva), mesoderm, anus develops first, water-vascular system → Deuterostome, Echinoderm.
6. Human – All deuterostome traits + vertebrae → Chordate/Vertebrate

> ✔ So we can make overlapping circles:
> - One circle for all animals (cells with flagella)
> - One for bilateral animals (flatworm, earthworm, snail, fruitfly, starfish, human)
> - One for protostomes (flatworm, earthworm, snail, fruitfly)
> - One for deuterostomes (starfish, human)
> - One for vertebrates (human)

But again — Venn diagrams get cluttered with 8 items. That’s why we use cladograms!

---

## 🌳 STEP 3: Build the Cladogram (Text-Based)

We want to arrange organisms from least derived (most ancestral) to most derived, placing shared traits at branching points.

Key Principle:

> Organisms that share more recent derived traits are closer relatives.

Let’s list traits in evolutionary order (from oldest to newest):

1. Cells with flagella → all animals (ancestral trait)
2. Symmetry → jellyfish (radial), others (bilateral)
3. Bilateral symmetry → flatworm, earthworm, snail, fruitfly, starfish, human
4. Mesoderm → same as above (triploblasts)
5. Head develops first → only snail & fruitfly? Wait — actually, this is likely meant to be protostome development (mouth forms first). Let’s assume:
- “Head develops first” = protostome (mouth first)
- “Anus develops first” = deuterostome (anus first)
6. Segmented body → earthworm, fruitfly
7. Calcified shell → snail
8. Chitinous exoskeleton → fruitfly
9. Water-vascular system → starfish
10. Vertebrae → human

---

## 📊 Step-by-Step Cladogram Construction

Start with the outgroup: Sponge — lacks true tissues, symmetry, etc. → branches off first.

Then Jellyfish — has symmetry but not bilateral → next branch.

Then Flatworm — bilateral, mesoderm, but no coelom or segmentation → next.

Now split into Protostomes vs. Deuterostomes:

- Protostomes: Flatworm → Earthworm → Snail → Fruitfly
- Deuterostomes: Starfish → Human

Within Protostomes:
- Earthworm: segmented
- Snail: calcified shell
- Fruitfly: chitinous exoskeleton, segmented

Within Deuterostomes:
- Starfish: water-vascular system
- Human: vertebrae

---

## ✏️ TEXT-BASED CLADOGRAM

```
┌── Sponge
│
├── Jellyfish
│
└── Flatworm
│
├── Earthworm
│ │
│ └── Fruitfly
│
└── Snail
│
└── Starfish
│
└── Human
```

Wait — that’s not quite right. We need to place traits at nodes.

Better version with traits at branching points:

```
[Cells with flagella]
│
├── Sponge
│
└── [Symmetry]
│
├── Jellyfish
│
└── [Bilateral symmetry, Mesoderm]
│
├── Flatworm
│
└── [Protostome: Head develops first]
│
├── Earthworm [Segmented body]
│
├── Snail [Calcified shell]
│
└── Fruitfly [Chitinous exoskeleton, Segmented body]
│
└── [Deuterostome: Anus develops first]
│
├── Starfish [Water-vascular system]
│
└── Human [Vertebrae]
```

> 💡 Note: The placement of “Earthworm” and “Fruitfly” both having segmented body suggests they might be sister taxa — but in reality, arthropods (fruitfly) and annelids (earthworm) are both segmented protostomes, but not necessarily closest relatives. However, based *only* on this table, we group them together under “segmented”.

---

## 🧠 FINAL EXPLANATION

The cladogram reflects evolutionary history based on shared derived traits:

- Sponge is the outgroup — no true tissues.
- Jellyfish has radial symmetry — more complex than sponge but less than bilaterians.
- Flatworm is the simplest bilateral animal.
- Then we split into protostomes (mouth-first development) and deuterostomes (anus-first).
- Within protostomes: Earthworm (segmented), Snail (shell), Fruitfly (exoskeleton + segmented).
- Within deuterostomes: Starfish (unique water-vascular system), Human (vertebrae).

This tree is hypothetical and simplified — real phylogeny uses DNA, fossils, and more traits — but for this worksheet, it’s perfect!

---

## ✔ Final Answer (Cladogram Text Version):

```
┌── Sponge
│
├── Jellyfish
│
└── Flatworm
│
└── Protostomes
│
├── Earthworm (Segmented body)
│
├── Snail (Calcified shell)
│
└── Fruitfly (Chitinous exoskeleton, Segmented body)
│
└── Deuterostomes
│
├── Starfish (Water-vascular system)
│
└── Human (Vertebrae)
```

> 📝 To draw this on paper:
> - Start left with Sponge.
> - Branch up/down for each new trait.
> - Label each branch point with the key trait that defines the group.
> - Make sure organisms with more shared traits are closer together.

Let me know if you want a visual sketch or help labeling the Venn diagram too!