#### Related to [[Evolution]] --- ## How to read an evolution tree - The **start** of the tree shows the oldest ancestor. - Each **diverging branch represents a divergence in evolution**. This means that two populations of the same species developed differing traits over time. *(The diverging points are known as nodes).* - At the end of the evolution tree will be a selection of spices all of which came from the ancestors at nodes that they are **directly connected to**. *(These are known as tips).* >[!tip] >- As the tree gets larger *(going down or across)* that generally symbolizes the passing of time. >- You can think of the x or y axis as time. >- Think of evolution trees **as those things that hang above cribs!** They can rotate about any node and still be the same. >[!example] >![[Pasted image 20230206110153.png]] --- ## Who is more closely related? - To figure out how closely related two different species are travel backwards in time until you find the **most recent common ancestor of those two animals**. - **Whoever shares a *more recent* ancestor is more closely related.** - If two species both share the same **most recent** common ancestor as another species then they are both *equally closely related.* >[!quote] >![[Pasted image 20230206111649.png|800]] --- ## How to construct evolutionary trees - Always construct an evolutionary tree from the varying/*living* spices on the left towards their common ancestor on the right. - If a spices has a unique trait they must **branch from an intermediary common ancestor**. - Next connect spices that have the same trait. The **fewer animals share a trait the more recent the development of that trait should be.** --- #subpage