Progression of Classification
384 BC-2013
350 BC Aristotle
- Greek philosopher
- divided organisms into 2 groups - plants and animals
- divided animals into blood and bloodless
- also divided animals into 3 groups according to how they moved - walking, flying, or swimming (land, air, or water
Times
1400's
· Classifications of things based on....
· Similarities and resemblances
· Characteristics are inherited
1500s-1800s
· Knowledge comes from close observation and visual description
· Classification based on reproduction and relationships
· Competition and struggle to survive leads to selection of successful traits over time
1900s-2000s
· Earth is approximately 4.5 billion years old.
· The structure of DNA can be read
Top Historians
Carolus Linnaeus
- lived from 1707-1778
- devised a system of naming species that would take hold in the scientific community
- based on forms and reproductive structures he grouped relatd living things.
Jean-Baptiste Lamarck
- lived form 1744-1829
- Studied Geology and fossils
- He believed that the environment gives rise to adaptations (webbed feet for birds living near the shore), these changes were then past from parents to their offspring
Antoni van Leeuwenhoek
- lived from 1632-1723
- First person to describe single-celled organism called animalcules with his own handcrafted microscope
- He was influenced by Robert Hooke.
The Present day Classification
The modern classification is an extension of the system of classification proposed by Carolus Linnaeus. The present system of classification involves a series of graded taxonomic ranks called taxa which include phylum and family in addition to the four taxa introduced by Linnaeus.