- Classification based on evolutionary history, or phylogenetic classification, enables scientists to make reliable predictions.
- It also helps them understand the biological connections between species.
Criteria for Evolutionary Classification
- For classification to correspond to evolutionary relationships, it must satisfy two conditions:
- All organisms that share a common ancestor must be placed within the same taxonomic group.
- Each taxonomic group should include only species derived from that same ancestor.
- This ensures that each taxon represents a monophyletic group (a clade), not a mixture of unrelated organisms.
This approach ensures groups are monophyletic (include all descendants of a common ancestor).
Key Advantages of Evolutionary Classification
1. Predictive Power of Evolutionary Classification
- Because clades share inherited traits, discovering a new species within a clade allows scientists to predict its characteristics before direct study.
- This predictive value makes evolutionary classification especially useful in medicine, agriculture, and ecology.
- Bats:
- If a new species of bat is discovered, classification within mammals immediately allows predictions:
- Four-chambered heart
- Presence of hair and mammary glands
- Placenta and therefore a navel
- Endothermy (warm-blooded metabolism)
- If a new species of bat is discovered, classification within mammals immediately allows predictions:
- Daffodils (Narcissus):
- Some daffodils produce galanthamine, a drug used for treating Alzheimer’s disease.
- Because all Narcissus species share a common ancestor, it was predicted that other species would also produce alkaloids.
- Over 80 alkaloids have now been identified in daffodils, some with potential pharmaceutical applications.
