Read and build a cladogram

Grade 9 Science Worksheet

Circle the best answer.

1. 1.

   Ari builds a cladogram from the trait table of five animals. Which description fits the traits?

   • Trout, frog, lizard and dog branch apart at one node, with lamprey outside that group
   • Lamprey and trout share a node, and frog, lizard and dog join them at a later node
   • Lamprey branches first, then trout, then dog; frog and lizard share the last node
   • Lamprey branches first, then trout, then frog; lizard and dog share the last node
2. 2.

   Bo builds a cladogram of moss, fern and pine from the trait table. Which description fits?

   • Pine branches first; moss and fern share a node, since they sit side by side
   • Moss branches first; fern and pine share a node
   • Moss, fern and pine branch apart at one node, with no closer pair
   • Fern branches first; moss and pine share a node

3. Read this first

   Traits of five model bugs (model data)

   Tips to place: J, K, L, M, N. No tree is drawn.

   bug	three-part antennae	spotted back	hooked legs
   J	no	no	no
   K	yes	yes	no
   L	yes	yes	no
   M	yes	no	yes
   N	yes	no	yes

4. 3.

   Esme builds a cladogram of five model bugs from the trait table. Which description fits the traits?

   • J branches first; L and M share a node, since they are neighbors in the table
   • J branches first; K, L, M and N then branch apart together at one single node
   • J branches first, then K, then L, and finally M and N share the last node
   • J branches first; K and L share a node, M and N share a node, and the two nodes join

5. 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.

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

6. 4.

   Jun wants to mark where jaws first appeared on the cladogram. Which branch gets the mark?

   • The branch to node Y, before frog, lizard and dog split
   • The branch to node X, before trout, frog, lizard and dog split
   • The trout tip, because trout is drawn first among the jawed animals
   • The stem below node W, before lamprey split off

7. Traits of four plants (model data)

   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.

   plant	vascular tissue	seeds	flowers
   moss	no	no	no
   fern	yes	no	no
   pine	yes	yes	no
   flowering plant	yes	yes	yes

8. 5.

   Kira marks seeds on the plant cladogram. Where did seeds first appear, using the fewest changes?

   • The stem below node W, before moss branched off from the others
   • The pine tip and the flowering plant tip, with one mark on each tip
   • The branch to node X, before fern and the seed plants split
   • The branch to node Y, once, before pine and flowering plant split

9. 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.

11. 6.

    Milo looks for a clade on the cladogram. Which group of animals is a clade?

    • Lizard and dog, the descendants of node Z
    • Frog and lizard, because both have four limbs
    • Lamprey and dog, the two ends of the tree
    • Trout and frog, because they sit side by side
12. 7.

    Noah reads the clade that starts at node Y. Which animals does it hold?

    Use the picture in question 6.

    • Trout, frog, lizard and dog, the animals that descend from node X
    • Frog and dog, leaving out lizard because it sits between them
    • Lizard and dog, the animals that descend from node Z
    • Frog, lizard and dog, the animals that descend from node Y
13. 8.

    Ren flips the branches at node Y, so frog is now drawn last. Which statement about the redrawn tree is true?

    • Frog is now the closest relative of dog, because the two animals sit side by side
    • Frog is now the most advanced animal, because it is drawn last
    • Nothing changes about relationships; lizard and dog still share node Z
    • The relationships changed, because flipping moves the branches to new ancestors
14. 9.

    “rooted, not to scale” Tala swaps the branches at node W, so moss is drawn last. Which statement about the redrawn tree is true?

    • Moss now branched off last, because it is drawn last
    • Moss is still the outgroup, and the relationships are unchanged
    • Moss is now a descendant of node X, because its branch moved
    • Moss is now closest to the flowering plant, because the two sit side by side

15. Use this

    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 branches at every node swapped.

16. 10.

    Zee compares Tree B, with tips dog, lizard, frog, trout and lamprey, to Tree A, with lamprey first. Does Tree B show different relationships?

    • No; Tree B is Tree A flipped at every node, so the relationships are the same
    • Yes; dog is now far from lamprey, so the relationships changed
    • Yes; Tree B has frog beside lizard, so frog is now a closer relative of lizard
    • Yes; lamprey is now drawn last, so it is now the newest group