All flashcards
Flashcard 1: What is the main limitation of using only anatomical evidence to compare fossils and modern organisms?
Answer: Fossils are often incomplete or missing soft tissues. Bones fossilize better than muscles or organs.
Flashcard 2: Which option is the best anatomical match for homology: same bones, different functions; or different bones, same function?
Answer: Same bones, different functions. Homology means same structure, different use.
Flashcard 3: What does it suggest if a fossil shows a mix of traits from two different modern groups?
Answer: It may represent a transitional form between those groups. Shows evolutionary link between the two groups.
Flashcard 4: Identify the anatomical evidence that a snake’s tiny pelvic bones suggest about its ancestry.
Answer: Vestigial remnants indicating ancestors had legs. Leftover hip bones prove legged ancestors.
Flashcard 5: Identify the anatomical evidence that a whale pelvis suggests about whale evolution.
Answer: A vestigial structure indicating ancestors had hind limbs. Reduced hip bones prove land-dwelling ancestors.
Flashcard 6: Which option best indicates closer relatedness: same number and arrangement of limb bones, or same habitat?
Answer: Same number and arrangement of limb bones. Bone patterns show inherited traits; habitat is environmental.
Flashcard 7: Identify the best conclusion if two organisms share a function (flight) but have different internal structures.
Answer: They likely have analogous structures from convergent evolution. Different origins achieving similar function independently.
Flashcard 8: Identify the best conclusion if a fossil limb and a modern limb share the same bone arrangement.
Answer: They are likely homologous and share a common ancestor. Same bone pattern indicates inherited from same ancestor.
Flashcard 9: Which anatomical feature is most useful for identifying homology: internal bone pattern or overall shape?
Answer: Internal bone pattern. Bone arrangement reveals shared developmental patterns.
Flashcard 10: What is comparative anatomy?
Answer: Study of similarities and differences in organism body structures. Reveals evolutionary relationships through structural analysis.
Flashcard 11: What is a transitional fossil?
Answer: A fossil showing intermediate traits between older and newer groups. Links evolutionary stages with mixed characteristics.
Flashcard 12: What does the term "common ancestor" mean in evolutionary comparisons?
Answer: An ancestral species from which multiple species descended. The shared evolutionary origin point for related species.
Flashcard 13: Which type of structure is most associated with convergent evolution: homologous or analogous?
Answer: Analogous structures. Independent evolution of similar features for same purpose.
Flashcard 14: Which type of structure most strongly supports common ancestry: homologous or analogous?
Answer: Homologous structures. Same origin proves shared evolutionary history.
Flashcard 15: What is a vestigial structure?
Answer: Reduced remnant structure with little or no current function. Evolutionary leftovers from functional ancestral structures.
Flashcard 16: What is an analogous structure?
Answer: Similar function but different ancestry and internal structure. Convergent evolution creates similar solutions independently.
Flashcard 17: What is a homologous structure?
Answer: Similar structure due to common ancestry, possibly different function. Same origin, modified for various uses over time.
Flashcard 18: What is anatomical evidence in evolution when comparing modern and fossil organisms?
Answer: Body structure similarities and differences used to infer relationships. Comparing structures reveals evolutionary connections.
Flashcard 19: What is a transitional fossil?
Answer: Fossil showing intermediate traits between ancestral and later groups. Provides evidence of evolutionary transitions between groups.
Flashcard 20: What does the fossil record provide when comparing ancient and modern anatomy?
Answer: A timeline of structural changes across species over time. Shows evolutionary progression through preserved anatomy.
Flashcard 21: Identify the best conclusion if a fossil limb and a modern limb share the same bone pattern.
Answer: They are likely homologous and indicate common ancestry. Same bone patterns strongly indicate shared ancestry.
Flashcard 22: Identify the best conclusion if two wings have similar function but different internal structure.
Answer: They are analogous and likely evolved by convergent evolution. Different structures achieving similar function independently.
Flashcard 23: Which option best supports common ancestry: same function or same underlying bone arrangement?
Answer: Same underlying bone arrangement. Structural similarity indicates evolutionary relationship better.
Flashcard 24: Identify the anatomical feature that best indicates a whale evolved from land mammals.
Answer: Vestigial pelvic (hip) bones. Remnants from terrestrial ancestors prove evolutionary origin.
Flashcard 25: What is the main limitation of using only soft-tissue anatomy to compare fossils and modern organisms?
Answer: Soft tissues rarely fossilize, so evidence is often missing. Decomposition prevents preservation of most soft structures.
Flashcard 26: Which anatomical evidence is most commonly preserved for comparing fossils to modern organisms?
Answer: Hard parts such as bones, teeth, and shells. Mineralization preserves these durable structures best.
Flashcard 27: Identify the best inference if a fossil shows a reduced structure that is fully functional in ancestors.
Answer: The structure is vestigial, supporting descent with modification. Shows evolutionary reduction of once-functional features.
Flashcard 28: What is a derived trait (derived character) in anatomical comparisons?
Answer: A newer feature that evolved in a lineage and was not in ancestors. Distinguishes recent evolutionary innovations from ancestral traits.
Flashcard 29: What is an ancestral trait (primitive character) in anatomical comparisons?
Answer: An older feature inherited from distant ancestors and shared widely. Present in common ancestors and retained in descendants.
Flashcard 30: What is a homologous structure?
Answer: Similar structure due to common ancestry, possibly different functions. Indicates shared evolutionary origin despite functional differences.