6th Grade Science Benchmark Fall - Kayla Combs | Library

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Another way to understand how Earth's surface has changed is to look at the distribution of
extinct life-forms in the fossil record. In their research, the paleontologist and the geologist have found evidence that, more than 3 million years ago, the sea life on each side of Latin America was the same. (Today, the Pacific Ocean is to the west of Latin America, and the Atlantic Ocean is to the east.) Less than 3 million years ago, the sea life began to diverge and eventually became very different.

Which of the statements is true? Choose TWO correct answers.

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Which of the following statements is most correct?

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Which observation best supports your answer to Part A?

Some of the evidence of how the arrangement of the continents may have changed over time is illustrated in the current world map shown. 

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Compare the current world map on the previous page to the four maps above showing what Earth might have looked like millions of years ago. Based on the fossil distribution in the current world map, which of these is most accurate?

In this performance task, you will answer five questions.

A geologist is giving a lecture to help people understand why fossils are sometimes found in
unexpected places. This includes fossils of fish found in tall mountains and fossils of tropical
plants found in deserts. She will also discuss why the same fossils are found in different
locations thousands of miles apart and why they are not found in some places at all. She begins by explaining that Earth's surface is made up of many large slabs known as plates, which are constantly moving although very slowly. The movement of Earth's plates is known as plate tectonics. This movement helps explain why some fossils are found in strange places.

Questions 5-6
When plates meet, one plate will often slide beneath a second in a process called subduction, causing the second plate to push upward. Because of great pressure. the hard rock of the plate that sinks is often destroyed, along with any fossils contained in that part of the plate. At other times, plates will pull apart or slide alongside each other.
Examine the map on the previous page and the diagrams below closely to answer the following questions.

Fossils of the same animals found along the east coast of South America are found on the west coast of Africa. These are fossils of land animals that cannot swim long distances.

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Which of the following statements is most correct?

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Which observation best supports your answer to Part A?

The geologist next wants to explain why fossils of some fish are found high in the mountains. Not
far from the west coast of South America is a mountain chain called the Andes Mountains. The
average elevation of the Andes Mountains is 3,962 m (13,000 ft). High in the Andes Mountains,
many fossils of whales, fish and other marine life have been found.
To help you understand how fossils of marine life are found high in the mountains, study the map,
and answer the question that follows.

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How did marine fossils come to be high in the Andes Mountains? Choose the two best options.

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The paleontologist and the geologist now think that they have enough evidence to prove that Earth's Surface has changed over time. Scientists can see how landmasses once aligned by comparing which of the following?

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The geologist explains that there are additional reasons some areas don't contain fossils. Earth's surface is made up of three major rock types: metamorphic, igneous and sedimentary.
Fossils do not occur in igenous rock because it comes from magma found deep within Earths mantle. When sedimentary rock transforms into metamorphic rock the fossils are destroyed. Which process most closely describes the transformation?

Next, the geologist wants to explain why some locations have very few fossils or none at all. In a
few places, there are hot spots in Earth's crust. These are volcanic areas that do not exist along
the perimeter of the Pacific Plate. Instead they occur where convection currents inside Earth
cause heated magma to rise to the surface. As a plate moves over a hot spot, volcanoes can
erupt. Examples of hot spots include Iceland and Hawaii.
The Hawaiian Islands formed from massive lava flows that created a series of islands over
millions of years. The oldest and smallest of the state's large islands is Kauai, which formed
about five million years ago, while the largest and most active is the island of Hawaii.
Examine the map, and then complete the activity that follows.

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Hawaii has very few fossils. Look at the map, and consider what you have learned so far. Explain why the island of Kauai is smaller than the island of Hawaii and why there are so few fossils on any of the islands.