You discover a new group of velvet worms in New Zealand. Some species in this group lay eggs; some species in this group give birth to live young. Based on this feature, you decide to classify the egg layers into a new genus you name Ovophera and classify the live young bearers into a new genus you name Viviphera. You collaborate with a colleague to determine the phylogeny of this group using DNA sequence data. Answer the following questions assuming that transitions between O and V happen a minimum number of times (ie, base your answer on the most parsimonious reconstruction of changes).

(a) Assume you obtain the tree below, with the distribution of Ovophera (O) and Viviphera (V) species as shown.

O O V VV O OOO

Is Ovophera monophyletic, paraphyletic, or polyphyletic?

Is Viviphera monophyletic, paraphyletic, or polyphyletic?

Based on this tree, would you predict that the ancestor of all the species in your tree laid eggs, bore live young, or you can't tell? Justify your answer.

(b) You then learn that your collaborator had a DNA contamination problem in the lab that renders the first tree (in 3a) invalid. The DNA contamination issue is resolved and a new phylogeny is generated, with the following distribution of Ovophera and Viviphera species:

O OOOOO V VV

Is Ovophera monophyletic, paraphyletic, or polyphyletic?

Is Viviphera monophyletic, paraphyletic, or polyphyletic?

Based on this tree, do you predict that the ancestor of all the species in your tree laid eggs, bore live young, or you can't tell? Justify your answer.

Answer rating: 100% (QA)

a The monophyletic is a clade that has common antecedent and all ... View the full answer