BIODIVERSITY, CHANGE AND CONTINUITY

1. BIODIVERSITY, CHANGE AND CONTINUITY Evolution Introduction • Why evolution • Nature of Science

2. WHY EVOLUTION? • Evolution as a PROCESS is • a SETTLED THEORY accepted by • biologists all over the world. • Evolution provides a framework for • understanding all aspects of biology • (classification e.g. simple to complex • organisms, adaptation e.g. function, • environment & structure)

3. WHY EVOLUTION? Cont. Evolution is integral to medicine and agriculture studies / research such as - Biotechnology, GMO e.g., generate insulin by bacteria, - Tracing evolutionary origins of diseases, - Selective breeding of plants and animals, - Resistance of insect pests to insecticides

4. WHY EVOLUTION? Cont. • Evolutionary biology provides tools for many studies in genetics/genomics • Relationships between groups, • Research, • Resolving legal issues such as DNA fingerprinting & Sources of AIDS • infections,

5. Nature of Science • Science seeks to explain the natural world and its explanations are tested using evidence from the natural world. • Scientific ideas are developed through reasoning. • What we know from scientific study is based on inferences from data.

6. Nature of Science Characteristics of science • Conclusions of science are reliable, though tentative. Might change over time • Science is non-dogmatic. • Science cannot make moral or aesthetic decisions. • Science is not democratic. Science is based on evidence, not votes.

7. Nature of Science • Facts: Accepted to be true and universal • Hypothesis: An educated guess which is testable based upon observation(s) • Theory: A scientific theory is accepted to be “true” by the scientific community as a whole.

8. Nature of Science Scientific Theory

9. The Development of a Simple Theory • Observation: Every swan I've ever seen is white. • Hypothesis: All swans must be white. • Test: A random sampling of swans from each continent where swans are indigenous produces only white swans. • Publication: "My global research has indicated that swans are always white, wherever they are observed." • Verification: Every swan any other scientist has ever observed in any country has always been white. • Theory: All swans are white. • Prediction: The next swan I see will be white.

10. The Development of a Simple Theory (Cont.) • Note, however, that although the prediction is useful, the theory does not absolutely “prove” that the next swan I see will be white. • Thus it is said to be falsifiable. If anyone ever saw a black swan, the theory would have to be tweaked or thrown out.

11. Evolution is NOT the process of superior animals triumphing over inferior ones, but is rather a series of alternative strategies that have arisen in response to changing environments.

12. No organism is better or worse than another. • Arthropods (crabs, spiders, insects etc.) are more successful than vertebrates when one considers the number of species, number of individuals, and number of adaptations to different environments and habitats. • In a similar way, humans are more successful than other modern apes in having a large number of individuals adapted to living in different environments.