1. Science and the Ways of Knowing

2. Equipped with his five senses, man explores the universe around him and calls the adventure Science. Edwin Hubble What is Science? Science is all those things which are confirmed to such a degree that it would be unreasonable to withhold one’s provisional consent. Stephen Jay Gould The title of one of Carl Sagan’s books: The Demon-Haunted World: Science as a Candle in the Dark

3. Science is A way of thinking that is both imaginative and disciplined; A balance between openness to new ideas and skepticism of claims unsupported by evidence; Based on the facts, even if they don’t conform to our preconceptions; Self-correcting. Science is an area of knowledge that comes with a built in error-correcting mechanism, and demands that scientific ideas be open to scrutiny by the “outside world”

4. Whenever scientific findings are published, the data is accompanied by error bars, describing how well we trust what we think we know. If the error bars are small, we have a greater confidence that the data is reliable and reflects how the world really is. The larger the error bars, the more variable the data and the less confident we are that a true relationship exists. The data may be suggestive, but further confirmation is needed before anyone will accept a conclusion based on such unconvincing data.

5. Scientists are very careful in the way they state their claims to understand the real world. Levels of confidence vary from educated guesses based on observations, called hypotheses, to scientific laws, which are meant to be simple, true, absolute and universal. Scientific theories explain a series of related hypotheses that have been critically tested multiple times and withstood all attempts to falsify them.

6. Rabbits average 6 babies per litter. OBSERVATION #1: All species have such great potential fertility that their population size would increase exponentially if all individuals that are born reproduced successfully. The world is not overrun by rabbits. OBSERVATION #2: Populations tend to remain stable in size, except for seasonal fluctuations. There’s only so much food and space available to rabbits. OBSERVATION #3: Environmental resources are limited.

7. Only some of the baby rabbits survive to adulthood. INFERENCE #1: Production of more individuals than the environment can support leads to a struggle for existence among individuals of a population, with only a fraction of offspring surviving each generation.

8. No two baby rabbits are exactly alike. OBSERVATION #4: Individuals of a population vary extensively in their characteristics; no two individuals are exactly alike. Rabbits reproduce sexually which leads to variation among offspring. OBSERVATION #5: Much of this variation is heritable.

9. INFERENCE#3: The unequal ability of individuals to survive and reproduce will lead to a gradual change in a population, with favorable characteristics accumulating over the generations. Law of Natural Selection: populations can change over generations if individuals that possess certain heritable traits leave more offspring than other individuals, thus leading to better adaptation of the population to its environment.

10. INFERENCE #2: Survival in the struggle for existence is not random, but depends in part on the hereditary constitution of the surviving individuals. Those individuals whose inherited characteristics best fit them to their environment are likely to leave more offspring than less-fit individuals. Well adapted rabbits contribute more offspring to the next generation than do less well adapted rabbits.

11. Theory of Evolution by Natural Selection – All species are descended from preexisting species through the gradual accumulation of genetic changes Lines of Evidence fossil evidence of species’ change over time embryology and conserved DNA sequences universal genetic code “molecular clock” of DNA anatomical evidence of homologous structures laboratory and field work with numerous species To date, there exists no scientifically credible evidence to falsify the theory of evolution – scientists accept it as TRUE until evidence emerges to suggest otherwise.

12. Should scientifically credible evidence appear, scientists will have to make what is called a Paradigm shift Thomas S. Kuhn – The Structure of Scientific Revolutions “scientific revolutions necessitated the community’s rejection of one time-honored scientific theory in favor of another incompatible with it. And each transformed the scientific imagination in ways that we shall ultimately need to describe as a transformation of the world within which scientific work was done. Such changes…are the defining characteristics of scientific revolutions.”

13. In astronomy: Ptolemy’s Heliocentric theory – The Copernican Revolution - Kepler’s Laws of Planetary Motion In Physics: Aristotle – Newton’s physics - Einstein’s physics – Quantum physics and the wave-particle duality of matter In Chemistry: Democritus’ ideas about atoms - Theory of elective affinity – John Dalton’s atomic theory - Niels Bohr’s planetary model – Modern electron cloud model and the Heisenberg exclusion principle

14. My favorite quote is from Niels Bohr, speaking of quantum physics: “If you aren’t confused you haven’t understood it very well.” Science requires us to give up our “naïve” notions of how the world works, in favor of experimentally demonstrated laws which we understand to be provisional. These laws are only as good as their ability to explain the data, that is, our perceptions.

15. Be open to new ideas, but be skeptical! question authority ask for the evidence consider the background assumptions reject pseudoscience – claims presented in scientific language but not rigorously tested using scientific methods