Evidence of common descent of living organisms has been discovered by scientists researching in a variety of disciplines over many decades, which can be interpreted as demonstrating that all life on Earth comes from a single ancestor.Evidence is from:Palaeontology - the study of fossils.Comparative anatomy - the study of similarities and differences in anatomy.Comparative biochemistry - the study of similarities and difference in the biochemical makeup and reactions of an organism.Comparison of the DNA genetic sequences of organisms has revealed that organisms that are phylogenetically close have a higher degree of DNA sequence similarity.
Evidence for Evolution
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Specification: OCR Biology A (H020), AS-level, 4.2.2 Classification and evolution. Topic: Classification and Evolution.
Key terms in this lesson
- pathogen
- A microorganism that causes disease.
- vector
- An organism, such as an insect, that transmits a pathogen from one host to another.
More in Classification and Evolution
- Archaebacteria and Eubacteria
- Phylogeny
- Advantages of Phylogenetic Classification
- Theory of Evolution
- Palaeontology
- Comparative Anatomy
- Comparative Biochemistry
- Types of Variation
All 36 lessons in Classification and Evolution · All OCR AS-level Biology topics