Self-study
Of the dinosaurs of the birdlike group called ornithomimids, the later ones had toothless beaks and weak jaw muscles. █ ██████ ██ ███ █████ ████████████ ███████ ██████████ ████████ ███ █████ ██ ████ ████████ ██ █ ████████ █████ ██████ ███ █████ ████ ██████ ███ █████ ██ ██████ █████ ███ ██████ ███████ ████ ██████ █████ ████ ██ ████ ████ █████ ███ ████ ███████████████ █████████ ███████████ ████ ██ ████████ ███ ██ █████████ ████ ████ █████ ███ ████
Summarize Argument: Phenomenon-Hypothesis
The paleontologists hypothesize that G. bullatus fed by filtering food from water and mud. They support this by noting that a fossil of G. bullatus had a comblike plate in its beak, similar to those found in ducks and geese today, which use them to strain food from water and mud.
Notable Assumptions
The paleontologists assume that G. bullatus could feed by filtering food from water and mud, and that factors like a very dry climate or a different diet didn't interfere with this. They also assume that the comblike plate had no other potential purpose that would better explain its presence, and that G. bullatus and modern ducks and geese are relevantly similar in enough ways to make the paleontologists’ hypothesis likely.
5.
Which one of the following, ██ █████ ████ ████████ ███ ███████ ███ ███ ████████████████ ███████████
a
Some dinosaurs with █████████ █████ ███ ████ ███ ███████ ███ ████████ ██ ████ ███████ █████ ████ ███ ██ ████ █████ █████
This fails to address the paleontologists’ key claim that G. bullatus’s comblike plate is evidence that it fed by filtering food from water and mud, nor does it help to make this hypothesis more likely.
b
Toothless beaks and ████ ███ ███████ ████ ███ ██████ ██ ███ ████████ █████ █████ ████ ██████████████
Like (A), this ignores the paleontologists’ primary argument, which is about the comblike plate, not the toothless beaks and weak jaw muscles. Also, we already know that G. bullatus was an ornithomimid with a toothless beak and weak jaw muscles, so (B) is irrelevant.
c
Except for the ████████ ██████ ██ █████ ██████ ██ ████████ ██████ ███ ██████████ ████████ ████ ██████ █████ ███ ██████
This weakens the paleontologists’ hypothesis by suggesting that G. bullatus and modern ducks and geese are not physically similar apart from their comblike plates.
d
Most G. bullatus ███████ ████ ████ █████ ██ █████████ █████████ ██ ██████ ███████ ███ █████ ███ █████████████
This strengthens the argument by affirming one of the paleontologists’ key assumptions. If G. bullatus fed by filtering food from water and mud, they must have lived near water and mud, so their fossils would likely be found there too.
Plausibility
Plausibility
Presenting evidence that corroborates (in Strengthen) or conflicts (in Weaken) with the author's hypothesized explanation or the predictions that follow from that explanation.
e
Paleontologists have not █████ ████████ ████ ███ █████████ █████ ████ ██ ████████ ███ ████████ ███████
We already know that G. bullatus did have comblike plates, and the argument is concerned with whether they also fed by filtering food from water and mud. Whether any other dinosaurs had comblike plates is not relevant to the argument.