In this Grade 7 Life Science lesson from Chapter 6, students learn how species change over time through the process of biological evolution, including early ideas proposed by Lamarck and Charles Darwin's development of the theory of natural selection based on his observations of tortoises and finches in the Galapagos Islands. Students explore key concepts such as adaptation and speciation, examining how new species can arise from older ones through inherited genetic changes. The lesson builds on prior knowledge of fossils and mass extinctions to help students understand the mechanisms driving evolutionary change across generations.
Section 1
Darwin Discovers Natural Selection Through Observations
Charles Darwin observed animal variations on the Galapagos Islands, including finches with different beak shapes adapted to specific food sources, leading him to develop his theory of natural selection.
Section 2
Evolution Changes Species Through Four Key Principles
Natural selection works through overproduction (many offspring), variation (differences among individuals), adaptation (beneficial traits), and selection (survival of organisms with advantageous traits).
Section 3
Geographic Isolation Creates New Species
When populations become separated by barriers like mountains or water, they evolve differently over time. These isolated groups eventually become distinct species that can no longer breed together.
Section 4
Organisms Pass Beneficial Adaptations to Future Generations
Organisms with traits that help them survive in their environment live longer and produce more offspring. These beneficial adaptations become more common in subsequent generations.
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Section 1
Darwin Discovers Natural Selection Through Observations
Charles Darwin observed animal variations on the Galapagos Islands, including finches with different beak shapes adapted to specific food sources, leading him to develop his theory of natural selection.
Section 2
Evolution Changes Species Through Four Key Principles
Natural selection works through overproduction (many offspring), variation (differences among individuals), adaptation (beneficial traits), and selection (survival of organisms with advantageous traits).
Section 3
Geographic Isolation Creates New Species
When populations become separated by barriers like mountains or water, they evolve differently over time. These isolated groups eventually become distinct species that can no longer breed together.
Section 4
Organisms Pass Beneficial Adaptations to Future Generations
Organisms with traits that help them survive in their environment live longer and produce more offspring. These beneficial adaptations become more common in subsequent generations.
Book overview
Jump across lessons in the current chapter without opening the full course modal.
Continue this chapter