Today is Thursday, May 3 DO NOW – Take clicker Take w/s & complete Life changes over time

Today is Thursday, May 3

DO NOW –

• Take clicker

• Take w/s & complete

Life changes over time

Today is Thursday, May 3

DO NOW –

• Take clicker

• Take w/s & complete

Life changes over time

Lessons 14 - 15 packets –

“Evolution”

Chp. 14-2 What Fossils Show

I. Fossils

A. Definition 1. The remains or traces of organisms that lived in the past B. Where found 1. Located in rocks, in tree sap, shells and other materials

II. Types of fossils A. Skeletons 1. Dinosaur skeletons are fossil types 2. Soft material/parts of an organism rapidly decay, bone and teeth become fossils for millions of years B. Sediment 1. If when an organism does and is buried in mud/dirt known as sediment and found below water 2. Over time layers of sediment harden into rock C. Mold 1. When trapped remains leave an impression 2. The mold is an empty space inside the rock a. materials or water may fill rock and harden into a cast

1. the cast resembles the remains that formed the mold

What do we know?

• Creatures have changed over time• How do we know this?

Fossil RecordFossil Record

OBSERVATIONOBSERVATION

What are the remains of the past known as?

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1. Crime scene evidence

2. Fossils3. Records4. Crumbs

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Which is not a type of fossil?

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1. Sediment2. Mold3. Teeth4. Bone5. Sap

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Which is NOT a place where a fossil would be found?

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1. Rocks 2. Ocean3. Living tree4. Dead tree

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III. The fossils record

A. Paleontologists 1. scientists who study life in the past, look for and study fossils 2. their findings form a fossil record

B. Fossil record 1. Tells how old fossils are 2. Tells how organisms have changed over time

What has the fossil record shown us?• Many creatures that lived in the past don’t

exist today

Origin of new species Origin of

new species

OBSERVATIONOBSERVATION

What has the fossil record shown us?• The creatures alive today haven’t

always been around

Different species lived in the pastDifferent species lived in the past

OBSERVATIONOBSERVATION

What has the fossil record shown us?• Many creatures in the past looked like living

ones we see today

“Family Tree”Relatives with similar,

but not the same traits

“Family Tree”Relatives with similar,

but not the same traits

OBSERVATIONOBSERVATION

C. Geological time scale 1. Tells the history of life on Earth 2. Life goes back 3.5 billion years 3. Shows life forms in each 4 time periods

EON ERA PERIOD EPOCHTIME SPAN(million years) AGE of

Phanerozoic

Cenozoic

QuaternaryHolocene

0-2

Mammals

Humans

Pleistocene

Mammals develop and become dominant

Extinction of dinosaurs (beginning of Paleocene) Tertiary

Neogene

Pliocene 2-5

Miocene 5-24

Paleogene

Oligocene 24-37

Eocene 37-58

Paleocene 58-66

Mesozoic

Cretaceous 66-144

Reptiles

Flowering plants, height of dinosaurs

Jurassic 144-208 1st birds/mammals, abundant dinosaurs

Triassic 208-245 First Dinosaurs

Paleozoic

Permian 245-286

Amphibians

End of trilobites & other marine animals

Carbon-iferous

Pennsylvanian 286-320 Abundant insects, first reptiles

Mississippian 320-360 Large primitive trees

Devonian 360-408Fishes

First amphibians

Silurian 408-438 First land plant fossils

Ordovician 438-505Marine Invertebrates

First Fish

Cambrian 505-5701st shelled organisms,

trilobites dominant

Proterzoic

Also known as Precambrian

570-2,500 First Multicelled organisms

Archean 2,500-3,800 First one-celled organisms

Hadean 3,800-4,600 Approx age of oldest rocks (3800)

The Geologic Time Scale

What do we know?• The Earth is very old• How do we know this?

Radioactive Datingof the Rocks

Radioactive Datingof the Rocks

TESTING & OBSERVATIONTESTING & OBSERVATION

Life is very old!Life is very old!

What’s happened to life during those billions of years?What’s happened to life during those billions of years?

This divides the history into time periods.

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1. Eras2. Time zones3. Geological time

scale4. Radioactive dating

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Scientists that study the life in the past are called

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1. Biologists2. Paleontologists3. Scientists4. Bone specialists

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Radioactive dating can be determined by the

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1. age of the rock2. energy given off by

the rock3. make up of the rock4. rock’s environment

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IV. Dating fossils

A. Relative age

1. Fossils can be dated by comparing their locations in rock 2. Relative age shows if older or younger than other fossils 3. Fossils in lowers areas are older than those in upper layers – as lower rocks were formed first

B. Actual age

1. Tells the numbers of years ago the fossil formed

2. Use radioactive mineral to determine

a. these minerals give off energy as they decay into another substance over time

3. Measured in units called half-life

a. time it takes for ½ the mineral to decay

Today is Monday, November 19th

DO NOW –

• Take clicker

• Take w/s & complete

Today is Monday, November 19th

DO NOW –

• Take clicker

• Take w/s & complete

True or false: Evolution can occur in a single organism.

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100%

1. True2. False

V. Extinction

A. Fossil record shows some organisms lived and one time then disappeared

B. When disappeared known as extinction

C. As one species becomes extinct, a new species appears

D. Mass extinction

1. Ending of a large new of species at one time

2. Dinosaurs and other reptiles became extinct about 65 million years ago

VI. Fossils and evolution

A. Fossils show how groups of organisms change over time 1. Evolution of an organism

B. Ex – horse

1. 50 million years ago a horse had 4 toes on front foot, less than 48 cm tall (about size of a dog)

2. As it evolved the 4 toes became a hoof and became larger

VII. Fossils and living organisms

A. Paleontologist learned more about fossils by comparing them to today’s living organisms

B. Look for similarities in teeth, structure and bones then compare environments

C. By studying they are able to discover relationships

VIII. Hunting for fossils today

A. Paleontologists still search for fossils today

B. As fossils are formed, they try to fit the info into the history of life on Earth C. New techniques and technology help scientists learn more info from fossils

1. DNA a. Compare fossil DNA to living organism’s DNA

b. Use this info to see how organisms evolved or the relationships between organisms

Mass extinction

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100%

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1. has never happened2. is the beginning of

life3. ends a large species

at one time4. will never happen

again

Rocks are measured in units called

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100%

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1. rockages2. lives3. half-life4. decayers

Rocks can be dated by

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1. the environment2. their layer location3. the amount of

decay

ASSIGNMENT:

- page 365 # 1 – 5

- w/s 14 - 2