Week 6- Quizzes, Animations, Clicker Questions Flashcards
A node on the phylogenetic tree indicates:
A., a branch point in evolution.
B., a common ancestor.
C., a branch point and common ancestor.
C., a branch point and common ancestor.
Why:
A taxon that includes a single common ancestor and all its descendants is a _____ group.
paraphyletic
polyphyletic
monophyletic
monophyletic
Why:
Of the following taxonomic categories, which is the MOST inclusive?
species
family
genus
order
class
Class
Why:
The nodes on a phylogenetic tree represent:
homologies.
common ancestors.
present-day groups.
sister groups.
descendant lineages.
common ancestors.
Why:
Which of the following statements is TRUE regarding a phylogenetic tree?
Given the sheer number of prokaryotic and eukaryotic species on Earth, it is impossible to create a phylogenetic tree encompassing all of these organisms.
Phylogenetic trees could be considered physical representations of hypotheses that seek to establish the evolutionary relationships between different organisms.
Within a phylogenetic tree, the order of groups located at the tree tips, not the nodes within a tree, determines sister group relationships.
Phylogenetic trees are constructed based solely on the morphological characteristics of species; sequence similarities among different organisms are only evaluated by taxonomists.
Phylogenetic trees only depict the evolutionary relationships between different classes; relationships among different species within the same genus are not illustrated in such trees.
Phylogenetic trees could be considered physical representations of hypotheses that seek to establish the evolutionary relationships between different organisms.
Why:
Seals and penguins both have streamlined body forms that allow them to move through water efficiently. This similarity in body shape is MOST likely the result of:
homology.
cladistics
shared ancestry.
convergent evolution.
phylogeny
convergent evolution.
Why:
Why might a phylogeny based only on molecular data show a different pattern of relationships than a phylogeny of the same taxa that is based only on morphological traits? (Select all that apply.)
Morphological analyses always provide more data because each morphological trait is the result of the expression of many genes.
Some highly conserved genetic sequences can result in unrelated species appearing closely related in a molecular phylogeny, and not reflect the same pattern as the morphologic phylogeny.
Gene sequences always provide more data than morphological traits.
The molecular data may be based on the analysis of introns, which aren’t expressed and don’t contribute to the evolutionary history of a group of taxa.
Gene sequence changes may not result in morphological changes
Some highly conserved genetic sequences can result in unrelated species appearing closely related in a molecular phylogeny, and not reflect the same pattern as the morphologic phylogeny.
Gene sequence changes may not result in morphological changes
Why:
Traits that are similar in two species as a result of common ancestry are referred to as:
homologous.
ancestral.
convergent.
analogous.
derived.
homologous
Why:
Imagine that a scientist discovers a new, flying species of mammal that resembles a winged rabbit. What can the scientist say about this organism?
If molecular sequence data show that bats and this new species do not share a common ancestor not shared by other mammals, the wings of bats and this new species would be considered homologous.
No data could support or disprove the hypothesis that the wings of bats and the new species are homologous.
If molecular sequence data show that bats and this new species share a common ancestor not shared by other mammals, the wings of these two species would be considered homologous.
If molecular sequence data show that bats and this new species share a common ancestor not shared by other mammals, the wings of these two species would be considered analogous.
Without any further information, the scientist can say that bat wings and the wings of this new species are homologous.
If molecular sequence data show that bats and this new species share a common ancestor not shared by other mammals, the wings of these two species would be considered homologous.
Why:
Which of the following is MOST likely to fossilize?
a leaf that fell from a tree and landed on the forest floor
a jellyfish that died and sunk to the bottom of the ocean
a crayfish that died in its muddy burrow by a creek
a lizard that died on a mountainside
a snail that died on a rock
a crayfish that died in its muddy burrow by a creek
Why:
Fossils’ contributions to phylogenetic trees include:
All of these choices are correct.
correlation between evolution and Earth’s environmental history.
time calibration.
records of extinct species.
All of these choices are correct.
Why:
Why is the fossil record of marine life more complete than that of organisms living in terrestrial ecosystems?
Marine habitats are places where sedimentation is more likely than erosion.
Organisms that live in terrestrial habitats are evolutionarily too old to fossilize.
Fossilization cannot occur without water acting to preserve body parts from decomposition.
Organisms that live in marine environments don’t have bones or other hard body parts.
Marine habitats are places where sedimentation is more likely than erosion.
Why:
Mass extinctions:
allow surviving species to proliferate.
represent loss of many species in a short time.
can be reconstructed from fossil records.
All of these choices are correct.
All of these choices are correct.
Why:
The LARGEST mass extinction occurred at the end of which period?
Devonian
Permian
Ordovician
Triassic
Cretaceous
Permian
Why:
The discovery of Tiktaalik roseae was significant for which of the following reasons?
It provided evidence that birds and dinosaurs are closely related.
It provided evidence that the continents were once linked together.
It was the first fossil to be found with soft parts preserved.
It was the first fossil from which DNA and other macromolecules were successfully extracted.
It provided evidence that terrestrial vertebrates are descended from fish.
It provided evidence that terrestrial vertebrates are descended from fish.
Why:
