Evidence Trails Exit Ticket
Evidence Trails
Exit Ticket: Heredity & Evolution
Standard 8.L.4
Agent Name
Date
Mission: Analyze the evidence provided in each scenario. Select the best answer that supports scientific claims about how organisms change over time or pass on traits.
1
Scientists have discovered that the bone structure in a whale's flipper is remarkably similar to the bone structure in a human arm and a bat's wing. What is the most likely scientific conclusion based on this evidence?
These organisms live in similar environments and evolved the same traits independently.
These organisms share a common ancestor that possessed a similar limb structure.
The structures are vestigial and no longer serve a functional purpose for the organisms.
Whales, humans, and bats are currently evolving into the same species.
2
A geologist finds a layer of sedimentary rock containing fossils of fish. In a layer directly above it, she finds fossils of early amphibians. Which claim is best supported by this fossil evidence?
The environment changed from land to water over a long period of time.
Amphibians and fish lived together in the same ecosystem at the same time.
Modern fish evolved from early amphibians found in the upper rock layers.
Biological evolution occurred as organisms transitioned from aquatic to terrestrial life.
3
In a population of beetles, most are green, but a few are brown. After a severe drought turns the green forest floor brown, the brown beetles survive and reproduce more successfully than the green beetles. How does this provide evidence for evolution?
It shows that individual beetles can change their color when the environment changes.
It demonstrates that genetic variation allows a population to adapt to environmental shifts.
It proves that the drought caused the beetles' DNA to mutate from green to brown.
It indicates that the beetle population will eventually go extinct due to the drought.
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Evidence Trails Answer Key
Evidence Trails
Answer Key & Teacher Guide
Standard 8.L.4
1
Question Focus: Comparative Anatomy
Which conclusion is best supported by similar bone structures in whales, humans, and bats?
Correct Answer: These organisms share a common ancestor that possessed a similar limb structure.
Rationale: This refers to homologous structures. The similarity in underlying anatomy, despite different functions, provides evidence for shared evolutionary descent rather than coincidental adaptation to similar environments (analogy).
2
Question Focus: Fossil Record & Geology
Which claim is best supported by finding amphibians in rock layers above fish fossils?
Correct Answer: Biological evolution occurred as organisms transitioned from aquatic to terrestrial life.
Rationale: The Law of Superposition places younger fossils above older ones. Finding amphibians (terrestrial/aquatic) above fish (aquatic) supports the claim of a historical transition in life forms over geological time.
3
Question Focus: Genetic Variation & Adaptation
How does the survival of brown beetles over green beetles during a drought provide evidence for evolution?
Correct Answer: It demonstrates that genetic variation allows a population to adapt to environmental shifts.
Rationale: Natural selection requires existing genetic variation (different colors). When the environment changes, certain variations provide a survival advantage, leading to a change in the population's trait frequency over time.
EOG Proficiency Alignment
3/3
Exceeds Proficiency
2/3
Meets Proficiency
0-1/3
Developing
