This presentation covers evolution and biodiversity. It discusses survival and extinction, defining species and populations. Examples are given of extinct species like the Baji Dolphin and endangered species like the Siberian Tiger and West African Black Rhino. Fossil records are explained as providing insight into Earth's history and how species have evolved. Charles Darwin and his theory of natural selection are also summarized, including differential survival, limited resources, and how the fittest species survive.
Evolution and Biodiversity in Bheki Hadebe's Presentation
1. 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!!
3. Survival and Extinction
Species :
A group of living organisms
consisting of smaller individuals capable of
interbreeding and exchanging genes.
Extinct Species
Endangered Species
•Baji Dolphin
•Siberian Tiger
•West African Black Rhino
MDPettitt, Siberian Tiger, July 17, 2008,
Creative Commons License
4. 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
7. Survival and Extinction
Fossil Records Continued
◦Displays how species have evolved
IvanWalsh, Fossils and Dinosaurs
from Beijing Museum, December 5,
2009, Creative Commons License
9. Evolution
Charles Darwin
Ryan Murphy M.Ed. www.sciencepowerpoint@gmail.com
◦ Created his own theory of evolution
◦ All species from common ancestry
◦ Branching pattern of evolution - natural selection
10. Evolution
Darwin’s Theory of Natural
Selection
◦ Differential Survival
◦ Essential to Darwin’s theory
◦ Limited quantities of space and resources
◦ Those most fit will survive
13. Natural Selection
The gradual non-random process through
which biological traits become more or less
common in a population
14. 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
15. 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