About Science

Exploring Nature and

Discovering the Order Within It

Brief History• Rational Thinking – trying to find out what

event causes what result (cause-and-effect)– Basis of science– Replaced superstition and magic

Brief History• Greeks

– Botany– Earth was round– Density– Water sanitation

• Chinese and Polynesians– Charted stars and planets

• Middle East– Developed Mathematics– How to make glass, paper, metals,

& certain chemicals

Modern Science• Began in 16th century with Galileo

– Revived Copernican view of

Sun-centered universe

Math and Science

• Math studies the relationship among numbers– Essential tool in

science

Math and Science• Can be used to show relationships:

– Direct Proportion:• As one increases, the other increases

– Ex: The more you study, the better you will do in this course

The longer you run, the farther you go

– Indirect Proportion:• As one increases, the other decreases

– Ex: The more time you spend watching TV, the less time you have to study

Scientific Method• Observations

• Objective (using facts), not subjective (using opinions)• Quantitative (counting or measuring) and qualitative

(describing)

• Problem• The problem is the question we want to answer• Must be specific and testable

• Hypothesis• A hypothesis is an educated prediction based on observations.• MUST BE TESTABLE.

• Capable of proven wrong = principle of falsifiability

• Predict• Predict consequences if hypothesis is true and false

Quantitative or Qualitative?

This flower is 6 feet tall.

This flower is yellow.

Scientific Method• Experiment

• An experiment tests the hypothesis• Controlled variables—factors that are kept constant

• Ex. sunlight, soil

• Manipulated variable—factor that changes (only have one of these at a time)

• Ex. Amount of water given

• Dependent variable—factor that changes (the thing you’re measuring).

• Ex. plant height

Scientific Method

• Data analysis• Data analysis is making

judgments or evaluations about the results of an experiment

• Use graphs, tables, and statistics

• Conclusion• A conclusion explains the

results of the experiment• Tell whether or not the

hypothesis was supported• Explain sources of error

Scientific Method• Retest (OR revise hypothesis)

• Experiment is redone many times

• Theory• A theory is a conclusion that is

accepted by many scientists that EXPLAINS something.

• Evolves over time with more evidence

• Law• A law describes behavior of natural

events

PROBLEM

OBSERVATIONS

HYPOTHESIS

EXPERIMENT

ANALYZE DATA

DRAW CONCLUSIONS

RETEST DISCARD

THEORY

Bubble Lab!

An Investigation of Sea Butterflies• Sea Butterfly

– Shell-less snail – Brightly colored– Winglike extensions used for

swimming

• Hyperiella dilatata– Amphipod

• Type of Crustacean

– Looks like a small shrimp

An Investigation of Sea Butterflies1. Observe:

– Many amphipods were carrying sea butterflies– If an amphipod lost a sea butterfly, it would abduct another– An amphipod with a sea butterfly would swim much slower

than one without; easier for predators to catch

Sea ButterflyAmphipod

An Investigation of Sea Butterflies2. Question:

• Why did amphipods abduct Sea Butterflies?

Sea ButterflyAmphipod

An Investigation of Sea Butterflies3. Hypothesize:

• Sea Butterflies produce a chemical to deter predators, which protects amphipods.

Sea ButterflyAmphipod

An Investigation of Sea Butterflies4. Predict:

• This chemical could be isolated• Amphipod predators are deterred by the chemical

Sea ButterflyAmphipod

An Investigation of Sea Butterflies5. Experiment:

• Fish (amphipod predator) were presented with:• Solitary Sea Butterflies• Solitary amphipods• Amphipod holding Sea Butterfly

Sea ButterflyAmphipod

An Investigation of Sea Butterflies6. Results:

– Solitary Sea Butterfly• Not Eaten

– Solitary amphipod• Eaten

– Amphipod with Sea Butterfly• Not Eaten

WAIT!

Could a chemical be the ONLY reason that the fish

didn’t eat the Sea Butterfly…

An Investigation of Sea Butterflies• The fish could have

not eaten the Sea Butterfly because:– Chemical Production– Feel of the Sea

Butterfly in the fish mouth

• The scientists did not control for these variables– Must do another

experiment…

An Investigation of Sea Butterflies5. Experiment:

• Fish were fed physically identical food pellets that:• Did not have the Sea Butterfly chemical • Had the Sea Butterfly chemical

• This was a controlled experiment: • Ideally designed so that only one variable changes

An Investigation of Sea Butterflies

6. Results:• Fish ate the pellets

without Sea Butterfly chemical (control)

• Fish did not eat pellets with Sea Butterfly chemical (experimental)

An Investigation of Sea Butterflies7. Conclusion:

• Amphipods abduct Sea Butterflies in order to use the chemical that Sea Butterflies produce to protect themselves from predators

Molecule found to deter predator fish

Sea ButterflyAmphipod

Technology The Practical Use of Science

• Science and Technology are different– Science: Gathering knowledge and organizing it– Technology: Uses knowledge gathered by science

for practical purposes• Both Good

• And Bad

Types of Sciences• Physical Sciences:

– Physics:• Motion, Force, Heat, Energy

– Chemistry:• Atoms, Molecules

– Earth Science:• Geology, Weather, Oceanography

– Astronomy:• Planets, Stars, Galaxies

• Life Sciences:– Biology

• Molecular Biology, Microbiology,

Ecology

Integrated Science• The physical and life sciences are not

isolated from each other – they overlap– Ex: Photosynthesis

• Not just biology…• Physics: Energy• Chemistry: Bonds breaking and forming• Earth Science: Gases in the Atmosphere• Astronomy: Sun

• To truly understand most topics, you need to study it using more than one type of science

Everything is Connected!