As you enter class: • Turn in any Safety Contracts to the HW folder (or the front desk) NEATLY, make sure your name is on them due Fri • Take the ½ for notes on the Nature of Science. • Sit quietly and be ready for class to begin
The Nature of Science The Nature of Science refers to the way scientific knowledge is developed. This is a general definition A better description of the way scientific knowledge is developed is…… 1) Scientific knowledge is TENTATIVE. Tentative means “subject to change” Sometimes scientific knowledge changes
Examples: Tentativeness Science is "subject to change"
Germ Theory states that disease is caused by micro-organisms. • Before GERM THEORY: • Around 1800 some doctors were beginning to speculate about germs or micro-organisms. This was mainly due to the invention of the microscope. • Those doctors that believed germs existed, believed they were the result of disease and not the cause of it! • This idea was called spontaneous generation.
Very recent change to science is…. ..is Pluto the planet, a planet? The scientific definition of a planet has changed, Pluto is no longer considered a planet by the International Astronomical Union Good Bye Pluto written August 25, 2006 Reuters News has reported that Pluto was stripped of its status as a planet on Thursday when astronomers from around the world redefined it as a "dwarf planet," leaving just eight major planets in the solar system. With one vote, toys and models of the solar system became instantly obsolete, forcing teachers and publishers to scramble to update textbooks and lessons used in classrooms for decades. Pluto is dead," Mike Brown of the California Institute of Technology bluntly told reporters on a teleconference. Discovered in 1930 by the American Clyde Tombaugh, the icy rock of Pluto has traditionally been considered the ninth planet, farthest from the sun in the solar system. However, the definition of a planet, approved after a heated debate among 2,500 scientists from the International Astronomical Union (IAU) meeting in Prague, drew a clear distinction between Pluto and the other eight planets. The need to define what is a planet was driven by technological advances enabling astronomers to look further into space and measure more precisely the size of celestial bodies. "This is all about the advancement of science changing our thinking as we get more information," said Richard Binzel, professor of Planetary Sciences at The Massachusetts Institute of Technology and a member of the planet definition committee. "The significance is that new discoveries and new science have told us that there is something different about Pluto from the other eight planets and as science learns more information, we get new results and new considerations." Brown added impetus to the decades-old debate on the definition of a planet when he discovered UB313 in 2003. Xena, as it is nicknamed, is larger than Pluto, instantly creating a buzz over whether a new planet had been discovered. The scientists agreed that, to be called a planet, a celestial body must be in orbit around a star while not itself being a star. It must be large enough in mass for its own gravity to pull it into a nearly spherical shape and have cleared the neighborhood around its orbit. Pluto was disqualified because its oblong orbit overlaps Neptune's. Xena also does not make the grade of being a planet, and will also be known as a dwarf planet.
GLOBAL WARMING??? IS IT REAL?? Some scientist argue that humans are causing an impact on the global environment. Some scientists are arguing that any changes in global environmental is due to natural causes or are cyclical. When does science stop changing?
The Nature of Science 2) Scientific knowledge is EMPIRICALLY-BASED. 1) Scientific knowledge is TENTATIVE. Empirical Based means… …based on experiment, experimental data. …based on observations and inferences. Scientific knowledge is developed by making inferences after collecting data, from experiments and observations. ??? Observation vs. Inference ???
The Nature of Science ??? Observation vs. Inference ??? What is an observation? How are observations made? An OBSERVATION is information collected with the senses. What is an INFERENCE? An INFERENCE explains observations. practice
The Nature of Science 2) Scientific knowledge is EMPIRICALLY-BASED. 3) Scientific knowledge is SUBJECTIVE. 1) Scientific knowledge is TENTATIVE. Subjective means “based on an individuals own thoughts and experiences” Examples: Who is tall? What is “Good Music”?
Practice! Even some observations can be subjective!
The Nature of Science 2) Scientific knowledge is EMPIRICALLY-BASED. 3) Scientific knowledge is SUBJECTIVE. 4) Scientific knowledge is built up by creativity and imagination. 1) Scientific knowledge is TENTATIVE. Scientist use their creativity and imagination to study and understand natural phenomena and to solve the problems.
The Nature of Science 2) Scientific knowledge is EMPIRICALLY-BASED. 3) Scientific knowledge is SUBJECTIVE. 4) Scientific knowledge is built up by creativity and imagination. 5) Scientific knowledge is Socially and Culturally embedded. 1) Scientific knowledge is TENTATIVE. Scientists are influenced by their societal and cultural values. Society rules and cultural rules often dictate what type of science is acceptable. Stem Cell Research: Is it right or wrong? Examples: Prescription medicine vs. natural treatment Western Medicine vs. Eastern Medicine
The Nature of Science Categories of Scientific knowledge: Observations/Data/Inferences, Hypothesis, Theory, Law. Social & Cultural Context. Relationship of the categories of Scientific knowledge: Social & Cultural Context Theory, Law Hypothesis, Observations/Data/Inferences,
The Nature of Science Scientific Law vs. Scientific Theory What is the difference? Scientific Laws Scientific Theories Boyle’s Law Kinetic Molecular Theory Mendel’s Laws of Inheritance Chromosome Theory Newton’s Laws of Motion Quantum Theory
The Nature of Science Scientific Law vs. Scientific Theory State, identify, or describe relationships among observable phenomena. Scientific Laws: Based on observations Scientific Theories: Inferred explanation for observable phenomena. Based on inferences
Review Read the following sentences, underline the observation and circle the inference. • The dinosaurs were fighting because all the fossilized footprints were jumbled up together. • The sky was changing colors from dark to light because the sun is rising. • Jenny’s mom burned dinner downstairs and Jenny could hear the smoke detector upstairs. • The kitchen is warmer than inside the freezer so Emmanuel Lewis’s ice cubes were melting on the counter.
Review Answers • The dinosaurs were fighting because all the fossilized footprints were jumbled up together. • The sky was changing colors from dark to light because the sun is rising. • Jenny’s mom burned dinner downstairs and Jenny could hear the smoke detector upstairs.
The kitchen is warmer than inside the freezer so Emmanuel Lewis’s ice cubes were melting on the counter.
Model Scientific Method(s) Curiosity General Format Observations/Measurements Hypothesis Testing/Experiments inconsistent results Results consistent results Theory Law