Classification
Kingdom
Phylum
Class
Order
Family
Genus
Species
Canis domesticus: Canis = genus, domesticus = species
Genus has an upper case 1st letter: Canis
Species has a lower case 1st letter: domesticus
Five kingdoms of living organism:
1. Kingdom Animalia - multicellular eukaryotes, heterotrophic nutrition, radial or bilateral symmetry
2. Kingdom Plantae – multicellular eukaryotes, cellulose cell walls
3.Kingdom Fungi – eukaryotes that reproduce by spore production
4. Kingdom Protoctista – e.g. amoeba
5. Kingdom Prokaryotae – no nucleus, circular DNA
Selection
Natural Selection (selection pressure)
- Organisms whose genes give them an advantage for survival - more likely to survive, reproduce and pass genes on
- Feature arises by random mutation, and survival determines whether feature is passed on through population
Artificial Selection Breeding
- Controlled for certain characteristics - new breeds but not new species
- When no selection pressure, characteristics are best suited for the environment in which an organism lives
Species
A population or group of similar organisms that can reproduce to produce fertile offspring
New species evolve by:
- isolation
- natural selection
- speciation
Evolution relies strongly on immigration and emigration
Evidence for evolution
- - fossil records,
- common blood pigments,
- similar larval forms (annelids and echinoderms),
- similar embryological development in mammals, fish and reptiles
