Based on the phylogeny shown, which species is not a tree but has seeds?

Question

A.  Psaronius

B.  ginkgo

C.  fern

D.  rose

E.  oak

F.  pine



Clarify Question

· What is the key concept addressed by the question?

· What type of thinking is required?

· What key words does the question contain and what do they mean?

 

Gather Content

· What do you already know about cladistics?

 

Consider Possibilities · What other information is related to the question? Which information is most useful?

 

Choose Answer

· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?

 

Reflect on Process

· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?

Answer 1

D.  rose

Clarify Question
· What is the key concept addressed by the question?
        o This question addresses cladistics.
· What type of thinking is required?
        o This question is asking you to take what you already know and apply it to this unfamiliar situation.
· What key words does the question contain and what do they mean?
        o A phylogeny is a diagram that represents a hypothesis about evolutionary relationships.
 
Gather Content
· What do you already know about cladistics?
        o Cladistics is the method used to construct a cladogram — a graphically represented hypothesis of evolutionary relationships.
        o Only shared derived characters (synapomorphies) are useful for inferring phylogenies, and they must be contrasted to an outgroup that has the ancestral characters.
        o Each nested clade is defined by a new shared derived character. These new characters are typically labeled on the branch.
 
Consider Possibilities · What other information is related to the question? Which information is most useful?
        o Normally, a new shared derived character would define a clade.
        o Here in this example, the feature ”tree” is shown as a character on three distantly related branches. There must have been many other characters that led researchers to believe that the plants became “trees” by convergent evolution.
 
Choose Answer
· Given what you now know, what information and/or problem solving approach is most likely to produce the correct answer?
        o The rose is shown above two character labels: “Seeds” and “Flowers”, but not above “Tree”.
        o So the rose is the member of this phylogeny that is not a tree but does have seeds.
 
Reflect on Process
· Did your problem-solving process lead you to the correct answer? If not, where did the process break down or lead you astray? How can you revise your approach to produce a more desirable result?
        o This question asked which species shown in the phylogeny has seeds but is not a tree.
        o The question required you to take what you already know and apply it to this unfamiliar situation.         o Did you recognize that the gray labels marked characters?