According to the theory of

Answer choices

1. A

   Correct94% picked this

   A large band of ancient rock of a rare type along the east coast of South America is of the same type as a

   Why this is right

   This helps increase the plausibility that South America's east coast and Africa's west coast were once connected. After all, a rare type of ancient rock is found in both places. If the continents weren't connected, then that means that this rare ancient rock just happens to exist on South America's east coast and Africa's west coast. It seems like this unlikely match between SA's east coast and Africa's west coast means that the continents were connected, but "ripped" apart in a seam that went through this patch of rare ancient rock. It's sort of like those friendship necklaces with a pendant that is half of a heart. Your friend wears a necklace with the other half of the heart. When you two are together you can put the jagged edge of your friend's pendant next to the jagged edge of your pendant and they 'magically' fit together to form a complete heart. If a stranger were witnessing you and your friend putting your half-heart pendants together to form a complete heart, would the stranger think, "Wow, that's an insane coincidence. These two people each bought half-heart pendants, and the pendants just happen to complement each other" or would they think, "Those two half-heart pendants were once together, sold in the same package, as a pair of friendship hearts". The wrong answers have much softer wording (many / some / several / similar / resemble). They also deal with portable things (language / plants) or omnipresent things (climate / genetic similarity). This answer is about a large band of rare, (non-portable) rock that is of the same type.

   Skill tested: Strengthen · how this choice captures the argument's function is the move to repeat next time.

   94%
2. B

   Too Weak1% picked this

   Many people today living in Brazil are genetically quite similar to

   "Many" isn't a precise quantifier, but as soon as you have a handful of things, you have "many". So this answer could be saying that "at least 5 people living in Brazil are genetically quite similar to at least 5 people living in western Africa". There are people living in the United States right now (Japanese Americans) that are genetically quite similar to many people who live in Japan. That's not strong evidence that the U.S. and Japan were once attached land masses. The idea of "genetically quite similar" is also a pretty weak concept. Humans are genetically quite similar to chimpanzees (98.7% of our genes are the same), so it's unsurprising that a human on any continent would be genetically quite similar to a human on some other continent. Also, the continents are thought to have broken apart tens of millions of years ago, and humans in their present form have only existed for about 100,000 years. So we wouldn't expect that there were any humans alive when the continents were together.

   1%
3. C

   Too Weak1% picked this

   The climates of western Africa and of the east coast of South America

   There are a lot of copy-cat climates throughout the world. Anything lying at a common latitude is likely to have fairly similar climates (unless the jet stream passes through and alters the climate). For example, London and San Francisco have climates that resemble each other, but that's not strong evidence that they were ever attached to each other.

   1%
4. D

   Too Weak: some2% picked this

   Some of the oldest tribes of people living in eastern South America speak languages linguistically similar to various languages spoken

   This just says that there's at least one tribe in eastern South America whose language is linguistically similar to some language in western Africa. That could be because "most languages are linguistically similar, no matter where humans live". That could be because people traveled by boat from South America to western Africa, or vice versa. We don't actually think that humans were alive when the continents were one big landmass, so we're not thinking that when the continents split apart, it took a human civilization and split it into being half South American / half African.

   2%
5. E

   Too Weak: several2% picked this

   Several species of plants found in western Africa closely resemble plants growing

   The fact that there are a few species of plants found in both places is very weak evidence. Corn, for example, is a plant species that may have originated in Nebraska. But humans can then take those seeds and grow corn in any similar climate anywhere in the world. If a human takes Nebraskan corn seeds and then grows corn in China, that doesn't give us strong evidence that Nebraska and China were attached land masses. If we were told that these plants were wild, uncultivated plants, that would make it a stronger answer.

   2%