Read and build a cladogram

Grade 9 Science Worksheet - Challenge Me

Circle the best answer.

1. Read this first

   Use this

   Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart. The mark for jaws is on the branch to node X. The mark for four limbs is on the branch to node Y. The mark for keratin skin growths is on the branch to node Z. Table: Traits of six animals (model data), 6 rows. Columns: animal | jaws | four limbs | keratin skin growths | feathers. Row 1: lamprey | no | no | no | no. Row 2: trout | yes | no | no | no. Row 3: frog | yes | yes | no | no. Row 4: lizard | yes | yes | yes | no. Row 5: pigeon | yes | yes | yes | yes. Row 6: dog | yes | yes | yes | no. Pigeon is in the table but is not yet drawn on the tree.

2. 1.

   Ari adds pigeon to the cladogram using only its new row in the table. Where does pigeon attach?

   • At node Z, as a third branch beside lizard and dog
   • Inside the lizard branch, because pigeon came from lizard
   • As the sister of dog, because feathers and hair are both body coverings
   • Below node Y, as the sister of frog, because both have four limbs

3. Traits of five animals (model data)

   Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart. The mark for jaws is on the branch to node X. The mark for four limbs is on the branch to node Y. The mark for keratin skin growths is on the branch to node Z.

   animal	jaws	four limbs	keratin skin growths
   lamprey	no	no	no
   trout	yes	no	no
   frog	yes	yes	no
   lizard	yes	yes	yes
   dog	yes	yes	yes

4. 2.

   Jun notes that a lizard and a frog can look more alike than a lizard and a dog, yet the tree pairs lizard with dog. Why?

   • The tree is wrong, because animals that look most alike must be closest relatives
   • Trees follow shared derived traits, and lizard and dog share keratin skin growths
   • Dog came from lizard, so the two are drawn together at node Z
   • The tree is mislabeled, since frog sits beside lizard and must be the closer pair
5. 3.

   Cladogram (model data), rooted, not to scale. Kira sees lamprey drawn first and dog drawn last, yet both groups live today. What does the order of tips mean?

   • Lamprey is the ancestor of the other four, which is why it is listed first
   • It is a drawing choice; only the nodes show how the groups are related
   • Lamprey is the simplest animal and dog the most advanced, so order shows progress
   • Flipping node W would move lamprey last and change how the animals are related

6. Traits of four organisms (model data)

   Cladogram (model data), rooted, not to scale. Tips from left to right: honeybee, trout, pigeon, dog. Node W is the root, where honeybee and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where pigeon and dog branch apart. The mark for backbone is on the branch to node X. The mark for four limbs is on the branch to node Y.

   organism	backbone	four limbs	wings
   honeybee	no	no	yes
   trout	yes	no	no
   pigeon	yes	yes	yes
   dog	yes	yes	no

7. 4.

   Luz sees wings marked yes for both honeybee and pigeon, yet the tree puts them far apart. What explains this?

   • Honeybee is the ancestor of pigeon, because it branches off first
   • Wings arose separately in each group, so they are analogous and show no closeness
   • Wings show that honeybee and pigeon are close relatives, so the tree must be wrong
   • Wings are a shared derived trait, so honeybee and pigeon should share node X

8. Use this

   Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, lizard, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and node Z branch apart. Node Z is where lizard and dog branch apart. Notebook: Notes on the animal cladogram (classmate's notebook), 4 lines. Columns: line, entry. Line 1: Node Z is the shared ancestor of lizard and dog. Line 2: The mark for keratin skin growths belongs on the branch to node Z. Line 3: Frog is drawn right beside lizard, so frog is the closest relative of lizard. Line 4: Lamprey is the outgroup for the other four animals.

9. 5.

   Milo reads a classmate's notebook about the animal cladogram. Which line has the mistake?

   • Line 4: lamprey cannot be the outgroup of the other four, because it is drawn first
   • Line 1: lizard and dog cannot share an ancestor if frog sits between them
   • Line 2: keratin skin growths belong on the lizard tip and the dog tip
   • Line 3: drawing order does not show closeness; lizard shares node Z with dog

10. Use this

    Cladogram (model data), rooted, not to scale. Tips from left to right: moss, fern, pine, flowering plant. Node W is the root, where moss and node X branch apart. Node X is where fern and node Y branch apart. Node Y is where pine and flowering plant branch apart. The mark for vascular tissue is on the branch to node X. The mark for seeds is on the branch to node Y. Notebook: Notes on the plant cladogram (classmate's notebook), 4 lines. Columns: line, entry. Line 1: Moss is the outgroup, so it branches off before the other three plants. Line 2: Seeds arose once, on the branch to node Y. Line 3: Pine is the ancestor of the flowering plant, so flowering plants came from pines. Line 4: Fern, pine and flowering plant share node X.

11. 6.

    Noah reads a classmate's notebook about the plant cladogram. Which line has the mistake?

    • Line 3: pine and flowering plant are sisters from node Y; neither came from the other
    • Line 2: seeds should be marked on the pine tip and the flowering plant tip
    • Line 4: fern cannot share node X with the flowering plant, because fern has no seeds of its own
    • Line 1: moss cannot be an outgroup because it lacks vascular tissue

12. Tree A tips from left to right

    Lamprey, trout, frog, lizard, dog. Tree B (model data), rooted, not to scale, is Tree A with the two branches at node Y swapped. Tips from left to right: lamprey, trout, lizard, dog, frog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where node Z and frog branch apart. Node Z is where lizard and dog branch apart. Notebook: Notes on Tree B (classmate's notebook), 4 lines. Columns: line, entry. Line 1: Tree B comes from Tree A by swapping the two branches at node Y. Line 2: In Tree B, frog is drawn right beside dog. Line 3: So Tree B shows frog as a closer relative of dog than lizard is. Line 4: Lizard and dog share node Z in both trees.

13. 7.

    Pia reads a classmate's notebook about Tree B, drawn here after the swap. Which line has the mistake?

    • Line 1: branches at a node cannot be swapped unless the tree also gains a new trait
    • Line 2: frog cannot be drawn beside dog in any cladogram that is drawn correctly
    • Line 4: node Z cannot be shared by lizard and dog in both trees, because the swap moved that node
    • Line 3: swapping does not change relationships; lizard is still the closest relative of dog
14. 8.

    Cladogram (model data), rooted, not to scale. Ren claims that lizard is a closer relative of dog than frog is. Which claim with its reason is best?

    • No, because the tree is read left to right, and frog comes first
    • Yes, because lizard and dog share node Z, which frog does not share
    • No, because frog and dog both have four limbs, so they must pair up
    • Yes, because lizard is drawn just before dog, so it is the ancestor

15. Traits of four animals (model data)

    Cladogram (model data), rooted, not to scale. Tips from left to right: lamprey, trout, frog, dog. Node W is the root, where lamprey and node X branch apart. Node X is where trout and node Y branch apart. Node Y is where frog and dog branch apart. The mark for backbone is on the stem below node W. The mark for jaws is on the branch to node X. The mark for four limbs is on the branch to node Y.

    animal	backbone	jaws	four limbs
    lamprey	yes	no	no
    trout	yes	yes	no
    frog	yes	yes	yes
    dog	yes	yes	yes

16. 9.

    Tala says a backbone shows that trout is closer to dog than to lamprey. Which reply with its reason is best?

    • Yes, because trout is the ancestor of dog and passed its backbone on
    • No, because lamprey has no backbone, so lamprey cannot be compared with trout and dog
    • No, because lamprey, trout and dog all have a backbone; jaws groups trout with dog
    • Yes, because trout and dog both have a backbone, so they are the closest pair
17. 10.

    Cladogram (model data), rooted, not to scale. Zee says moss, drawn at the far left, is the ancestor of fern, pine and flowering plant. Which reply is best?

    • No: moss has no traits in the table, so it cannot be an ancestor
    • Yes: tips on the left are older than tips on the right
    • No: moss is a present-day group on its own branch; the shared ancestor is node W
    • Yes: moss branches off first, so the other three plants came from moss long ago