Block1 Fossils

Study of Evolution The Fossil Record By: Nikki Kagan, Kayla Sigalos, Rohit Kundurthi

Defining Fossils

History of life

Remains or imprints of the organism from earlier geological periods

Can be found in rocks

Compare overlapping sequences

Benefits of Fossils

Acknowledges age to fossils

Provide information about climate and environment

Can unlock secrets of evolution

Can explain history of past geological habitation

How fossils are made

A process known as permineralization

Total replacement of original skeletal material by another mineral matter

Original components have been replaced by minerals deposited from water

The hard parts of the organisms can become buried in sediment rock

How to find Fossils

Start at the bottom of a creek

Look for fragments of bone

Follow them up the creek looking for larger, more angular bits as you go

When the bits of bone stop look up on the banks for the fossils

Find the larger piece of bone and excavate it

Cambrian Explosion

Happened 540 million years ago

Animals began to evolve

Over a period of 30 million years ancestors of large groups of animals living today appear in fossil records.

Organisms did not all appear at once

Discoveries

Radiometric dating indicates that earth was formed 4.5 billion years ago

The earliest fossils resemble microorganisms such as bacteria

The oldest fossils appear in rocks 3.5 billion years ago

The first vertebrates appeared about 400 million years ago

The fossil record is incomplete

Geological Time Period

Vendian Period, 600-540MYA

Cambrian Period, 540-500 MYA (new timescale)

Ordovician Period, 500-425 MYA

Silurian Period, 425-408 MYA

Devonian Period, 408-362 MYA

Carboniferous Period, 362-290 MYA

Permian Period, 290-245 MYA

Triassic Period, 245-208 MYA

Jurassic Period, 208-145 MYA

Cretaceous Period, 145-65 MYA

Tertiary Period, 65-1.64 MYA

Quaternary Period, 1.64 MYA - present

Cambrian Ordovician Triassic Quaternary Jurassic

Precambrian Era

Starts with the birth of earth

Many celled animals

570 million years ago

Primitive atmosphere

Later life saw a range of soft bodied creatures

Paleontologists

Scientists who study fossils

Find fossils by digging in

layers of sedimentary rock

Use scientific methods to find out more about the animal the fossil came from

Use picks, chisels, drills, shovels, and brushes.

Famous Paleontologists

Paul Sereno- found the first well preserved skull and completed skeleton of the oldest known dinosaur called Herrerasaurus ischigualastensis .

Gideon Algernon Mantell- discovered 4 of 5 genera of dinosaurs during the 1790’s

Meave Leakey- Found the first human fossil

Darwin’s Evolution Theory

Variation exists among individuals within species

Organisms produce more offspring than the environment can support

Competition exists among individuals

The organism whose variations best fit to the environment are the ones most likely to survive

Africa

All humans originated from Africa

Darwin said, “It is somewhat more probable that our early progenitors lived on the African continent than elsewhere.”

DNA Fossils

fossil record . ( 2009). In Encyclopædia Britannica. Retrieved April 13, 2009, from Encyclopædia Britannica Online: http://search.eb.com/eb/article-9101225

fossil . ( 2009). In Encyclopædia Britannica. Retrieved April 13, 2009, from Encyclopædia Britannica Online: http://search.eb.com/eb/article-9035001

evolution . ( 2009). In Encyclopædia Britannica. Retrieved April 13, 2009, from Encyclopædia Britannica Online: http://search.eb.com/eb/article-49846

http://www.britannica.com/EBchecked/topic/214564/fossil-record http://www.emerson.k12.nj.us/staff/rmkelly/Custom/Classwebpages/DreamBig/GroupB/JobPages/Paleontologist/BPaleontologist.html A Kansan’s Guide To Science. Page 9- the Cambrian explosion http://search.eb.com/search?query=famous+palientologists&ct=eb&fuzzy=true&autobounce=true http://www.earthsci.org/fossils/youngp/periods/periods.html#precambrian Citations!