Grade 10 - Biology - Evidence for Evolution

Study Notes

Types of Evidence for Evolution

Relative Dating:
- Determines fossil age by comparing its placement in layers of rock.
- Assesses sequential order of fossils to infer relative ages.
Radiometric Dating:
- Measures absolute age of geological materials.
- Utilizes concentrations of radioactive isotopes and their decay products for precise dating.
Fossil Record:
- Provides comprehensive information on past life forms.
- Contains details such as organism structure, diet, predators, habitat, and chronological order of existence.
Biogeography:
- Studies the geographical distribution of plant and animal species.
- Sheds light on evolutionary processes influenced by physical landscapes.
Anatomical Homology:
- Involves comparison of body structures (homologous structures) across species.
- Indicates common ancestry through similar bone arrangements.
Embryo/Developmental Homology:
- Examines similarities in structures that arise from the same tissue during embryonic development.
- Highlights shared developmental pathways among different species.
Cellular/Molecular Homology:
- Focuses on similarities in gene or protein sequences among species.
- Reflects shared ancestry at a molecular level, supporting evolutionary relationships.
Analogous Structures:
- Features shared by unrelated species as a result of convergent evolution.
- Demonstrates how different organisms develop similar adaptations in response to similar environmental challenges.
Adaptation:
- Refers to the evolutionary process by which species adjust to environmental conditions.
- Enhances survival and reproduction through beneficial traits.
Artificial Selection:
- Human-directed breeding for specific traits from natural variations in organisms.
- Demonstrates selective pressure and its role in evolution.
Experimental Evidence:
- Involves laboratory or field experiments that can manipulate conditions.
- Helps to test hypotheses about evolution by observing effects on organisms.