In this Grade 7 Life Science lesson from Chapter 6, students explore the multiple lines of evidence that support the theory of evolution, including fossil evidence, vestigial organs, and similarities in biological structure. Students learn how scientists use common ancestors, structural comparisons, and ongoing field research to strengthen Darwin's theory of natural selection. The lesson also clarifies what distinguishes a scientific theory from everyday use of the word, helping students understand how observations and experiments build widely accepted scientific explanations.
Section 1
Scientists Use Multiple Evidence Types to Support Evolution
Fossil records, biological structures, embryonic development, and DNA sequences provide scientists with compelling evidence that species change over time through natural selection and common ancestry.
Section 2
Darwin Gathered Evidence to Develop Natural Selection Theory
After his voyage on the Beagle, Darwin collected fossils and observed species variations across different locations, carefully analyzing his findings before publishing his theory of evolution in 1859.
Section 3
Similar Structures Reveal Evolutionary Relationships
Animals like lizards, bats, and manatees share similar bone structures but use them differently. These similarities indicate common ancestry, while differences show adaptations to varied environments through natural selection.
Section 4
DNA Sequences Connect Related Organisms
Scientists compare genes like the "clock gene" across species. The more similar the DNA sequences, the more closely related the organisms are, regardless of their physical differences.
Section 5
Vestigial Organs Trace Evolutionary History
Structures like whale leg bones and snake leg remnants were once functional in ancestors but are now reduced or unused. These organs provide evidence of species' evolutionary relationships to earlier forms.
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Section 1
Scientists Use Multiple Evidence Types to Support Evolution
Fossil records, biological structures, embryonic development, and DNA sequences provide scientists with compelling evidence that species change over time through natural selection and common ancestry.
Section 2
Darwin Gathered Evidence to Develop Natural Selection Theory
After his voyage on the Beagle, Darwin collected fossils and observed species variations across different locations, carefully analyzing his findings before publishing his theory of evolution in 1859.
Section 3
Similar Structures Reveal Evolutionary Relationships
Animals like lizards, bats, and manatees share similar bone structures but use them differently. These similarities indicate common ancestry, while differences show adaptations to varied environments through natural selection.
Section 4
DNA Sequences Connect Related Organisms
Scientists compare genes like the "clock gene" across species. The more similar the DNA sequences, the more closely related the organisms are, regardless of their physical differences.
Section 5
Vestigial Organs Trace Evolutionary History
Structures like whale leg bones and snake leg remnants were once functional in ancestors but are now reduced or unused. These organs provide evidence of species' evolutionary relationships to earlier forms.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter