What is Science? Advanced Animal Science c (2) (a)(b)(c)(d)

What is Science?

Advanced Animal Science c (2) (a)(b)(c)(d)

Objectives• Today you will be able to:– Summarize the definition and importance of

science– Describe a hypothesis– Describe a scientific theory– Compare hypotheses and theories– Synthesize a hypothesis for given situations

How do we define science?• Science, as defined by the National Academy of

Sciences, is the "use of evidence to construct testable explanations and predictions of natural phenomena, as well as the knowledge generated through this process."

What does it really mean?• Science is a tool to understand how the universe

works around us. • Science is a system of acquiring knowledge.– A system of observation and experimentation used to

describe and explain phenomena.

• Scientific discovery takes a long time, and is the interconnection of many different studies and existing knowledge

Why? Why is it important?• Through explanations and knowledge gained through science,

we are able to improve our lives.

• What has science done for you?

University of California, Berkeley

Products of Modern Science• Electricity– Observations and experimentation by Ben Franklin

and Alessandro Volta in the 1700s pioneered the way for harnessing the power of electricity.

• Modern Medicine– Through science, we enjoy the benefits of:• Vaccines• Eradication of diseases such as smallpox• Extended lives through the treatment of once deadly

diseases

– Many people alive today are here because of the benefits that modern medicine provided them.

Products of Modern Science

• Modern Agriculture– Science has played a key role in developing a

safe and abundant food supply in developed countries.

– Specialized biologists (plant breeders) started developing high-yielding varieties of crops through new techniques in breeding.

– Today biotechnology plays an essential role in further transforming our food system, ensuring we have a plentiful and safe food supply for future generations.

Products of Modern Science

Impact of Science on Society• Those were some examples of products of

modern science. Almost everything we enjoy today is the result of science.

• Science also enables us to make informed personal and policy decisions concerning health, agriculture, economics, etc.

• As a result, it is extremely important to understand science and distinguish between “bad science” and “good science”.

• Groups can take advantage of ignorance to push their agenda.

THE SCIENTIFIC METHODWhat is Science?

The Scientific Method• As we discussed, science is a system of observation and

experimentation.

• This system of observation and experimentation is the scientific method. The scientific method is the engine behind science.

• List out what you feel are the steps of the scientific process.

The Scientific MethodGeneral Principles

HYPOTHESISWhat is Science?

Hypotheses

• After your observations/researching existing information about issue, you will form an educated guess to answer your question.

• Hypothesis is defined as: “a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation”.

Hypotheses

• Basically, it is a suggested solution for an unexplained occurrence that does not fit into current accepted scientific theory.

• It must be worded so that it can be tested, and subsequently answered.

• This is called falsifiability and testability.

Hypotheses

• In order to make it testable, you express your hypothesis using an independent variable and dependent variable.

• Independent Variable (IV): variable you change

• Dependent Variable (DV): you observe changes of this variable with the changes of the IV.

EXAMPLE SCIENTIFIC EXPERIMENT

Example Experiment

• Define a Question: “What happens if I water a plant with different liquids?”

• Information gathering: research on the methods water is absorbed through the plant

• Hypothesis: “Normal water with little to no additives is the most effective liquid to water”.

This is the variable you change.

Independent Dependent Control

ExampleUsing various liquids to “water” a plant versus

your control: water.

You collect data on this variable based off of

the changes you make to the independent

variable.

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ExamplePlant height

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Unchanged, constant.

ExampleType of plant, soil.

Plant water

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Types of Variables

Example Scientific Experiment

Soda Orange Juice Vinegar Water

Plant #1 10.2 12.4 4.5 19.8

Plant #2 12.6 11.9 6.7 21.5

Plant #3 11.7 10.5 5.9 21.9

Plant #4 9.8 11.3 6.4 22.3

Water Treatment (IV)

Height

(in)

Raw Data

Example Scientific ExperimentSoda Orange Juice Vinegar Water

Plant #1 10.2 12.4 4.5 19.8

Plant #2 12.6 11.9 6.7 21.5

Plant #3 11.7 10.5 5.9 21.9

Plant #4 9.8 11.3 6.4 22.3

Water Treatment (IV)

Height

(in)

Data AnalysisSoda Orange Juice Vinegar Water

Mean 11.075 11.525 5.875 21.375

Standard Deviation (σ) 1.305 0.818 0.974 1.100

Implications/Conclusion

• What would your conclusion be given this data?

• Recommendations?

Soda Orange Juice Vinegar Water

Mean 11.075 11.525 5.875 21.375

Standard Deviation (σ) 1.305 0.818 0.974 1.100

THE NEXT STAGE: THEORIESWe have tested hypotheses – now what?

Hypothesis

Theories• A scientific theory is a well-substantiated

explanation for natural phenomena. – Theory is the result of repeatedly testing and

confirming hypotheses with the use of the scientific method.

Hypothesis

Hypothesis Hypothesis

Scientific Theory

Theories• The US National Academy of Sciences defines

theories as:– The formal scientific definition of theory is quite

different from the everyday meaning of the word. It refers to a comprehensive explanation of some aspect of nature that is supported by a vast body of evidence. Many scientific theories are so well established that no new evidence is likely to alter them substantially.

Theories

• The common usage of the term theory does not reflect scientific theory.

Examples of Theories

• What are some examples of theories?

Examples of Theories

• Heliocentric theory– The model in which the Earth and planets revolve

around the Sun at the center of the Solar system.– Is this a fact?– It serves as an example of how many theories are

well established and no new evidence can substantially alter them.

Examples of Theories

• Germ theory of disease:– States that some diseases are caused by

microorganism• Cell theory:– Cells are the basic unit of structure in all

organisms and also the basic unit of reproduction.

Distinguishing: Hypotheses and Theories

Hypotheses• Suggested explanation for

an observable phenomenon• Prediction of a possible

relationship between two events

• Very specific – focused on certain events

Theories• Well-established, unified

explanation • Developed after a set of

proven hypotheses• Based on a wide set of data • It is a general principle

Identifying

• Hypothesis or Theory?

“If I add a certain amount of growth regulator to this plant, it will cease growing taller.”

Identifying

• Hypothesis

• Why?

• Specific• Suggestion, prediction• Predicting a correlation among events

Identifying

• Hypothesis or Theory?

• “Based on the studying of fossils and the modern distribution and reproduction of organisms, natural selection is how life has developed through the ages.”

Identifying

• Theory

• Why?

• General• Well-substantiated, unified explanation• Repeated testing, evidence

ACTIVITY

Activity

• In groups, develop a plan for a scientific experiment.

• Draw out and explain all the steps for the scientific theory for your experiment.

• Remember: the scientific process is methodical and intricate. It’s important to make sure the experiment is accurate.

ASSESSMENT

Assessment

• What is a scientific hypothesis?• What are the steps of the scientific theory?• Describe each step of the scientific theory– Provide examples

• Compare and contrast hypotheses and theories