Bheki Hadebe This is the presentation by Bheki Hadebe from different authors, for more details find the credits page on the last slide. Hope you will find this info useful. Enjoy the
Bheki Hadebe
This is the presentation by Bheki Hadebe from different authors, for more details find the credits page on the last slide. Hope you will find this info useful.
Enjoy the lesson!!
Evolution and Bio-Diversity
•Survival and Extinction•Theory of Evolution•Natural Selection
Survival and Extinction
Extinct Species•Baji Dolphin
Endangered Species•Siberian Tiger•West African Black Rhino
Species : A group of living organisms consisting of smaller individuals capable of interbreeding and exchanging genes.
MDPettitt, Siberian Tiger, July 17, 2008, Creative Commons License
Survival and Extinction
◦Population – A group of organisms of one species that interbreed and live in the same place at the same time.◦Example:◦ Deer Population
LoneTown, Deer ‘White Tail Deer’, February 20, 2011, Creative Commons License
Survival and Extinction◦Removal of genes from gene pool
Survival and Extinction
◦Fossil Records
◦Majority of species are extinct◦Give us insight to Earth’s history
Survival and Extinction
Fossil Records Continued ◦Displays how species have evolved
IvanWalsh, Fossils and Dinosaurs from Beijing Museum, December 5, 2009, Creative Commons License
EvolutionEvolution Definition
◦Any change across successive generations in the heritable characteristics of biological populations
Evolution Charles Darwin
Ryan Murphy M.Ed. [email protected] ◦Created his own theory of evolution ◦All species from common ancestry◦Branching pattern of evolution - natural selection
EvolutionDarwin’s Theory of
Natural Selection◦Differential Survival ◦Essential to Darwin’s theory◦Limited quantities of space and resources◦Those most fit will survive
Evolution Best displayed through
comparisons of: Fossils
Modern species
Changes are displayed in different ways
EvolutionNatural Selection
◦Provides a mechanism for evolution◦Process to explain evolution
Natural Selection
The gradual non-random process through which biological traits become more or less common in a population
Natural Selection
How it works◦Traits are passed down generations◦Beneficial traits are passed on◦Negative traits disappear ◦Important traits are traits that:◦Benefit reproduction and/or survival
Natural Selection◦Mutations◦Some diversity comes from mutations◦Beneficial mutations are passed on◦Mutations can become part of genes◦Example: Giraffes’ long necks
JRobertMoore, Giraffe, January 13, 2007, Creative Commons License
Natural Selection Geographic Isolation
◦A species is physically separated◦Plays important role in evolution◦Two diverse groups form
Natural Selection◦Environmental Factors◦New predators or prey◦Low food supply◦Finite resources
Credits to:◦ Pettitt, M. D. (2008: 17). Siberian Tiger. Creatice Commons License. ◦ Lonne Town, Deer White Tail Deer. (2011: 20). Creative Commons
Licenses . ◦ Ivan Walsh. (2009, 05). Fossils and Dinosaurs. Beijing Museum. ◦Moore, J. R. (2007: 13). Giraffe. Creative Commons License. ◦[email protected] ◦ Ryan Murphy M.Ed. [email protected]