Practice Flashcards
Flip to reveal answersWhat is a cladogram?
Track your progress — Sign up free to save your progress and get smart review reminders based on spaced repetition.
All 6 Flashcards — Analysing cladograms
Sign up free to track progress and get spaced-repetition review schedules.
Question
What is a cladogram?
Answer
A branching **tree-diagram** showing the **most probable evolutionary relationships** among groups (clades), based on the best current evidence.
Question
What does a node on a cladogram represent?
Answer
A **common ancestor** — the point where one ancestral lineage **diverged (split)** into two lineages.
Question
How do you find the two most closely related groups?
Answer
Find the pair whose branches meet at the **most recent node** (nearest the tips) — they share the **most recent common ancestor**.
Question
What is the root of a cladogram?
Answer
The **deepest (oldest) node**, on the far left — the **common ancestor of every group** on the tree.
Question
Why are some groups more distantly related than others?
Answer
Their branches meet only at a **deep node (near the root)**, so their **common ancestor is much older** — they diverged earlier.
Question
Why is a cladogram only a hypothesis?
Answer
It shows the **most probable** relationships from the **evidence available** (now mainly DNA). New evidence can lead to it being **revised**.
Read the notes
Full study notes for Analysing cladograms
Topic 1.7 hub
Classification and cladistics
More from Topic 1.7
All flashcards in this topic
Biology exam skills
Paper structures & tips
Track your progress with spaced repetition
Sign up free — Aimnova tells you exactly which cards to review and when, so you remember everything before your IB exam.
Start Free