Investigation: Phylogenetic Trees

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This page is a draft and is under active development.

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Part 1: Is a dog more closely related to a coyote or a wolf?

wolf 1.png

Gray Wolf

Species Name: Canis lupus

Color: Light gray to black

Size: 80-120 pounds, 2.5 feet tall

Appearance: broad snout, round ears, long tail

wolf 2.png

Coyote

Species Name: Canis latrans

Color: Light gray to brown

Size: 20-50 pounds, 1.5 feet tall

Appearance: narrow snout, pointed ears, long tail

wolf 3.png

Dog, Alaskan Malamute

Species Name: Canis lupus familiaris

Color: Gray and white or brown and white

Size: 70-80 pounds, 2 feet tall

Appearance: broad snout, round ears, long tail

Examine the images and descriptions above. Underline any similarities between the dog and the wolf. Place a star ✭ next to any coyote traits that are similar to the dog.
Based on appearance alone, which do you think is the most closely related to a dog?

Part 2: Phylogenetic Trees

Once scientists learned how to sequence DNA, that became a great resource for determining relationships. A phylogenetic tree shown below is based on DNA evidence and similarities in appearance.

wolf 4.png

3. Branch points are called “nodes” and they indicate a more recent common ancestor from which each branch species has descended from.

- Place a box to indicate the node or common ancestor of all the fox species.

- Place a triangle to indicate the node or common ancestor of all the canis species.

4. Which two members of the canis group have the most recent common ancestor?___________________

5. A species name has two words, a system called BINOMIAL NOMENCLATURE. The first word of a species name refers to its GENUS. For example, wolves, coyotes and dogs all belong to the genus “CANIS.”

What is the genus for the foxes? ________________________________

6. In some cases, a third name is given to the animal to indicate a SUBSPECIES.

What animal on the chart is a subspecies? _______________________________________

What is this animal’s full scientific name? _______________________________________

7. Final Synthesis: Is a dog more closely related to a coyote or a wolf? ______________________ Provide EVIDENCE from the phylogenetic tree to support your position.

8. Extension: Is a red wolf or a domestic dog more closely related to a common fox? Use the phylogenetic tree to explain your answer.

Follow up video on dog evolution: ~ 5 minutes

https://www.nytimes.com/video/scienc...come-dogs.html