What is Science?

What is science?What is science?Science is that activity, the

underlying aim of which is to further our understanding of

why things happen as they do in the natural world.

It accomplishes this goal by applications of scientific method—the process of

observing nature, isolating a facet that is not well

understood, and then proposing and testing possible

explanations.-S. Carey, 2004

What is science?What is science?

Way of knowing

Study of natural world (process)

Involves observing, proposing explanations, testing explanations

Evidence-based

CURIOSITY! ASK WHY.

What is science?What is science?

Know, use and interpret scientific explanations of the natural world

scientific knowledge (content)

Generate and evaluate evidence and explanations

scientific reasoning, using evidence (process)

What is science?What is science?

Understand the nature and development of scientific knowledge

how science works (nature of science)

Participate productively in scientific practices and discourse

how to talk/think about science, how to use scientific knowledge, engage in scientific practice

Be careful…

Sometimes we think science can do things it can’t OR does more than we think--there are

about science

Video: Science Myths

Common Science Myths

When exposed to the vacuum of space, the human body pops.

a human can survive for 15 – 30 seconds in outer space as long as they breathe out before the exposure

Food that drops on the floor is safe to eat if you pick it up within five seconds Um, no..but eating germs and dirt is not always a bad thing as it helps us to develop a robust immune system

Common Science Myths

Brain cells can’t regenerate – if you kill a brain cell, it is never replaced.

In 1998, scientists at the Sweden and the Salk Institute in La Jolla, California discovered that brain cells in mature humans can regenerate. An old dog CAN learn new tricks!

A penny dropped from a very high building can kill a pedestrian belowthe aerodynamics of a penny are not sufficient to make it dangerous. What would happen in reality is that the person who gets hit would feel a sting

The Nature of The Nature of ScienceScience

Content, process, nature

How does science lead to new knowledge?

What can science do?

What can’t it do?

a Nature of Science quiz…a Nature of Science quiz…What do What do youyou know about science? know about science?

(Answer True or False)(Answer True or False)

1) Science is a system of beliefs.

2) Scientists are totally objective in their work

3) The scientific method is the basic, 5-step guide for conducting scientific research.

4) Doing science involves creativity.

5) Scientific ideas are tentative and can be modified or disproved, but never proved.

1. Science is a system of beliefs

Many students, science teachers, and the general public often believe that science is a system of beliefs

Scientific ideas are established only after compelling evidence has accumulated from observations of nature.

Scientists use reasoning and imagination, study the work of other scientists, and collaborate with other professionals, always looking for evidence to support or disprove their ideas.

FALSE

2. Scientists are totally 2. Scientists are totally objective in their work. objective in their work.

Science involves some subjectivity. Humans do sciencehumans are

subjective SO…science involves subjectivity

Personal experience and expectations influence observations

How do we "get around" this? Controlled settings Repeat tests Confirmation from other observers Large sample sizes

FALSE

Perceptions Take out a piece of paper.

Place one of your hands in the middle of the paper.

On the RIGHT side of your hand draw a small cross.

On the LEFT side of your hand draw a dime size circle.

Hold the paper at arms length and cover your right eye.

While staring at the “cross” slowly bring the paper towards your face.

Perceptions

Perception is not always reality.

The natural world is full of illusions, and simple common sense doesn't always work to explain such illusions.

What do you see?What do you see?

What do you see?What do you see?

What do you see?What do you see?

Inference is when observations are influenced by prior knowledge and beliefs

Being able to infer is a survival mechanism, so it is positive.

Inference doesn’t make science weak, but rather forces us to be careful in our observations and interpretation of evidence

Video: Inference vs. Observation

What happened here?What happened here?

What do you OBSERVE?

Now what do

you think?

Infer what happened based on your observations.

Observation Any information collected with the

senses.

The skill of describing scientific events.

__________Inference______________

Conclusions or deductions based on observations .

The process of drawing a conclusion from given evidence.

What happened here?What happened here?

Be sure to distinguish observation and inference.

Prior knowledge affects observation! Not all evidence leads to one answer.

Not all scientific knowledge is gained through controlled experiments. (Paleontology for instance)

3. The 3. The scientific method scientific method is the is the basic, 5-step guide for basic, 5-step guide for

conducting scientific research.conducting scientific research. There is no universal scientific

method.

There are methods, but not a single pathway

Observations (before, during, after) Proposing explanations based on

observation Testing explanations or predictions

FALSE

Observations

Definition

Using senses to gather

information

Observations lead to

questions

How does sand How does sand grain size affect grain size affect the size and the size and abundance of abundance of crabs?crabs?

Two types of Observations

Qualitative:

Uses senses to describe

Ex: color and consistency of sand, minerals present etc.

Quantitative:

Uses tools to take a numerical measurement

Ex: actual size of grains, actual size and number of crabs at various sites.

Hypothesis

Predicts the answer to a

question

Hypothesis are based on:

Past experience

Observations

Research

It must be testable

Written as “If…..then” statements.

Experiment: Procedure to test your prediction.

Experiments

Variables: Factor in the experiment that is tested.

Scientific Experiments Scientific Experiments Follow RulesFollow Rules

An experimenter changes one factor and observes or measures what happens.

Other Variables

The factor that is being changed is known as the independent variable.

The factor that is measured or observed is called the dependent variable.

The Control VariableThe Control Variable

The experimenter makes a The experimenter makes a special effort to keep other special effort to keep other factorsfactors constant constant so that so that they will not effect the they will not effect the outcome.outcome.

Those factors are called Those factors are called control variablescontrol variables..

What is the Purpose of What is the Purpose of a Control?a Control?

Controls are NOT being tested

Controls are used for COMPARISON

Remember: To be a Remember: To be a Valid Experiment:Valid Experiment:

Two groups are required --- the control & experimental groups

There should be only one independent variable

DataData Results of

the experiment

May be quantitative (numbers) or qualitative

DataData Must be

organized

Can be organized into charts, tables, or graphs

ConclusionConclusion

The answer to the hypothesis based on the data obtained from the experiment

ConclusionConclusion

My conclusion [supports/does not support] my hypothesis because ____________________.

RetestRetest

In order to verify the results,

experiments must be retested.