Mystery of theMystery of the

Matching MarksMatching Marks

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DO I HAVE YOUR ATTENTION?

For some reason, a GUNSHOT seems to suggest a CRIME SCENE…

with BULLETS…

and BULLET MARKS…

4

How are these marks used to solve crimes?

5

RIGHT!They are used to COMPARE

bullets found at a crime scene,

with bullets that werefired from suspect guns

6

Here are the marks from a crime scene bullet…

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and here are the marks from bullets fired from four possible suspect

guns…A B

C D

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Which bullet matches the crime scene bullet?

A

Crime Scene:

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B

Crime Scene:

Which bullet matches the crime scene bullet?

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C

Crime Scene:

Which bullet matches the crime scene bullet?

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D

Crime Scene:

Which bullet matches the crime scene bullet?

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RIGHT! It’s a bullet shot from gun C.

So what does that tell us?

C

Crime Scene:

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YOU’VE GOT IT! The Crime Scene bullet and bullet C came from the

SAME GUN !

C

Crime Scene:

We could say the bullets had a “Common Origin”

Many studies have told us that when any two items

with COMPLEX PATTERNS MATCH EACH OTHER

perfectly, we can be confident

that they had a…

COMMON ORIGIN !

KEEP THIS IN MIND:When we find other

COMPLEX PATTERNS that MATCH,

What does this tell us?They had a…

“COMMON ORIGIN”

This is our theme:Matching Complex Patterns =

COMMON ORIGIN

What is this?

Right, it’s a HUMAN KARYOTYPE

A Human Karyotype has photos of all the matched pairs of human

chromosomes from one cell, stained to show banding patterns,

and arranged from long to short, with centromeres near the top.Here are our numbers 6-9…

On the next slide, you will see another kind of human

karyotype:It has diagrams of

the chromosomes, with only one member of each

pair, clearly showing their banding patterns…

And on the next slide, you will see a similar

diagrammatic karyotype,

but this is from a NON-HUMAN

SPECIES…

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NEXT, we wll see both karyotypes together,

showing the matching chromosomes side by side:

each human chromosome is on the left…

each NON-human chromosome is on the right

As you COMPARE the CHROMOSOMES,side-by-side,

what is MOST surprising?

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What is most surprising?

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Did you notice how very SIMILAR they are? Here’s a closer look at the first

seven:

Any identical ones? What did we say about

items with IDENTICAL COMPLEX PATTERNS?

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RIGHT!Identical Patterns = COMMON

ORIGINHow would this apply

to two different SPECIESwith IDENTICAL banding patterns

on their CHROMOSOMES?

RIGHT!They MUST have a Common Origin, or

a COMMON ANCESTOR !

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Time for a Revelation…

The clear chromosome evidence

of identical banding patterns

tells us that humans andchimpanzees must have had

a…

The non-human species is

the CHIMPANZEE

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Somewhere, in our distant past,there was an ape-like species

thatgave rise to two lines of

ancestry.One branch led to modern

CHIMPS, the other branch led to HUMANS.

COMMON ANCESTOR !

DNA analysis and fossils tell us that

this split was around 6-7 million years ago (6-7 mya)

<---Common Ancestor

Chimps Us

6 mya

NOW

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That’s pretty strong stuff...

And seems to conflict with Traditional Views!

Is there any other evidence that supports this conclusion?

Let’s take another look at thosechromosomes… [next set of slides]