Looking at the two pictures, can - PowerPoint Presentation

Slide1

Looking at the two pictures, can you describe how this form of communication has changed over time?Slide2

Essential Question:How do scientists define and support the theory of evolution?

Standards:

S7L5a. Explain that physical characteristics of organisms have changed over successive generations (e.g. Darwin’s finches and peppered moths of Manchester)

S7L5c. Trace evidence that the fossil record found in sedimentary rock provides evidence for the long history of changing life forms.Slide3

Describe the evidence scientists use to determine that Earth changes over time.

Give an example of how Earth has changed over time.Slide4

Evidence of life’s history on earth is provided by fossils.

Fossils

are the remains

of organisms preserved in

the earth.Slide5

Fossils can consist of bones, bone fragments, imprints, and preserved remains.Slide6

Most fossils are found in sedimentary rock. Why?

Fossils are primarily found in sedimentary rocks because these rocks form at low temperatures and pressures.Slide7

Some organisms become fossilized in ice or amber.Slide8

Scientists observe fossil characteristics and make inferences concerning the life of the organism based on these observations.Slide9

Once scientists piece the fossil below together, what might they be able to know about the once living organism?Slide10

How can scientists tell that the first organisms lived in oceans, or that dinosaurs lived on land and that they disappeared 65 million years ago?

These questions and others can be addressed by determining the age of fossils.

Scientists use relative dating and absolute dating to describe the age of fossils.Slide11

Older fossils are found in deeper layers of the earth’s sedimentary rock; younger fossils are found in the upper layers of the earth’s sedimentary rock.Slide12

The fossil record and the geologic time scale provide reference to when and how long organisms have existed on planet Earth.Slide13

The fossil record is the

total number of fossils that have been discovered, as well as the information gained

from

them.Slide14

The geologic time scale

is

a system of chronological measurement that

describes

the timing and relationships between events that have occurred throughout Earth's history.Slide15

Turn to an elbow partner and answer the question below. Discuss how to determine the correct answer.Slide16

With the same elbow partner describe the changes in the fossils you see in each layer and what they tell you about that time period.Slide17

Turn to a different partner. Compare layer C to layer F in the diagram below.

W

hat evidence do these fossils provide of changes on earth?Slide18

Complete the Using Fossils to Gather Evidence

of Once Living Organisms WorksheetSlide19

Mr. Parr Fossils SongSlide20

Evolution is the process through which species change over time.Slide21

Evolution is a scientific theory.

A scientific theory is a statement based on observation and experiment. If continued observation and experiment support the statement, it may become widely accepted.Slide22

Activities to demonstrate Evidence and Theory

[see resources]

D and T Sentence

The

Great Fossil Find Activity

Xenosmilus

ActivitySlide23

Look at the two images below. The image on

the left

shows

the

skull

of a

fossil, the

Swift

Fox

(

Vulpes

velox

), compared

to the same view of a modern Kit Fox (

Vulpes

macrotis

). With a partner, identify the similarities.Slide24

The

Swift

Fox (on the left) was alive

during the

Pleistocene Epoch. Find the Pleistocene Epoch on the Geologic Time Scale diagram to the right.Slide25

If the

Swift

Fox was alive about 1 million years ago, why is it so similar to the modern Kit Fox? Slide26

Look at these three organisms. Each fossil comes from a different time on the Geologic Time Scale. Are they similar? How?Slide27

What can we learn from these two fossil comparisons?Slide28

Living or once living things share common ancestors and fossils provide evidence for common ancestry.

Physical characteristics of organisms change over time and fossils provide evidence of change.Slide29

Living or once living things share common ancestors and fossils provide evidence for common ancestry.Slide30

Physical characteristics of organisms change over time and fossils provide evidence of change.Slide31

Evidence to support the Theory of Evolution…

Fossils provide evidence of evolution as the previous slides demonstrated.

What other evidence might support evolution?Slide32

Similarities in Structure and Development provide evidence for the Theory of Evolution.Slide33

Vestigial Structures are physical structures that were fully developed and functional in an ancestral group of organisms but are reduced and unused in later species.Slide34

Vestigial Structure Examples

In the bodies of whales there are small leg bones

The skeletons of snakes also have traces of leg-like structures that are not usedSlide35

Vestigial Structure Examples

Vestigial toe in the horseSlide36

Why Some Humans Are Born With Tails VideoSlide37

Similar Structures with Different FunctionsSlide38

Similarities in Development

Organisms that appear to be very different as adults are similar during early development.Slide39

Scientists can also tell how closely organisms are related by comparing their genetic material (DNA).Slide40

In the previous slides we have identified the following evidence of evolution: Fossils, Similarities in Structure and Development, and DNA.

Which of the these three main types of evidence do you think would best help scientists prove the relationships among the organisms?

Slide41

A

Cladogram

or a Branching Diagram are often used to illustrate common ancestry and evolution.Slide42

Which organisms have fur and mammary glands?

Common

AncestorSlide43

Which organisms have lungs?

Common

AncestorSlide44

https://www.youtube.com/watch?v=_

C6cqsOf2mI

Common

AncestorSlide45

The organisms’ characteristics have changed over time, but they share a common ancestor.Slide46

Which organism(s) in the branching diagram will have the greatest physical difference from its ancestor? Why?Slide47

A.

B

.

C

.

D

.

Where is the location of the common ancestor for all of the organisms shown?Slide48

A.

B

.

C

.

D

.

What is meant by the dotted lines and question marks?

There are missing pieces in the fossil record.Slide49
Slide50

With a seat partner, compare and contrast the information Figure 1 will provide to the information Figure 2 will provide.

Figure 1

Figure 2Slide51

Evidence of Evolution Video:

https://

www.youtube.com/watch?v=lIEoO5KdPvg

Slide52

Summarizing Strategy: 3 – 2 – 1

Describe three ways in which scientists support the theory of evolution

.

Identify two ways in which scientists know the physical characteristics of organisms change over time.

Describe why the fossil record is important.