Self-Guided Tour of the Fossil Discovery Center

7/28/2019 Self-Guided Tour of the Fossil Discovery Center

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: 12-14 ft.

: 11,00022,000 lbs.*

*Body weight is difficult to gauge because fateaves no impression on the skeleton.

Columbian Mammoth (Mammuthus Columbi)

Asian ElephantClosest modern day

Relative

*This mammoth was named after the location of the

first discovery - the Columbia Plateau.

Steppe MammothMost recent ancestor

Woolly MammothCousin

About the exhibit

Adult Columbian Mammoths were only preyed upon

humans; however, the younger mammoths were preye

upon by Sabertooth Cats. How we know: 441 milk tee

(the teeth below your gums when you are born) of

Columbian Mammoth calves were found in Freisenhahn

Cave, Texas, alongside Sabertooth Cat remains.

The most common causes of death in adult mammoth

were accidents, human hunters, and starvation.

Predators Columbian Mammoths lived in North America as far back as

1.1 million years ago and occupied southern Canada to

central Mexico, but never made it into South America.

The Columbian Mammoth is believed to be a greatswimmer. We find their remains on the Channel Islands

and there has never existed a way to get there by land.

Also, the Mammoths that made it to the Channel Islands

underwent extreme genetic dwarfing, we call them Pygmy

Mammoths.

Columbian

Mammoth

Fossil

Locations

The Columbian Mammothskeleton in front of you is

replica. A replica is an exactcopy of the original bone

(there is a diagram explaining how they are made on th

7th stop of your tour the lab!). Replicas are importan

because otherwise you wouldnt be able to see the enti

animal skeleton. The original bone is too fragile, too he

and much too valuable to try and assemble.

Also, we needed to get this replica because we never

find an entire skeleton. The Fairmead bones were

scattered by predators and scavengers before they wer

covered in sediment by local flood water. The mammo

before you is from Florida.

Next Exhibit: Mammoth

Teeth and Tusk


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Columbian MammothTeeth

Characteristics: 5-8 enamel plates per 3.9 in.*Weight: The molar is approx. 8 lbs.*All mammoths are identified primarily by features oftheir teeth!

Lower jaw of a Columbian Mammoth

About theExhibits The specimens on the table are real fossils. On the left side of the table, marked with a 1, the

are two remnants ofColumbian Mammoth molars

and a partial rib. They are encased in a Plaster of

Paris and burlap jacket.

In the center of the table, marked with a 2, you casee a tusk fragment. Notice the growth rings inside

of the tusk? Unfortunately we cannot tell the age o

the mammoth by counting the rings but

paleontologists can extract data from them such as

the season of death, age at sexual maturation,

calving, and migration. On the right side of the table, marked with a 3, yo

see a Columbian Mammoth molar that has been

partially damaged by the heavy equipment at the

landfill.

Beside the table stands a tusk that was discovered 2006 and took 3 days to excavate. It is still encased

in the silty clay in which it was buried.

Tusks

Both males and females had tusksbut male tusks were longer and

heavier.

The tusks were used to dig forfood, fight during mating season,

and to defend against predators.

Mammoth tusks growcontinuously.

They are actually the mammothstwo front teeth (incisors)!

Molars

Columbian Mammoths gothrough 6 sets of molars in their

life time.

New molars grew in from the backof the jaw rather than under the

old tooth. It would push the old

ground down tooth out of the

mouth like a conveyor belt.

The old ground down tooth thatgets ejected is called a spit

tooth.Next Exhibit: The Dig Diorama


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Basic tools used: Chisel tip hammers, screw

drivers, brushes, tin foil, toilet paper, and

anything that can dig through hard soil.

The Excavation Process First, paleo-monitors will follow behind the heavy equipment

carrying orange flags that they use to mark off an area thatthey think a bone occupies. Afterwards they will go back to the

flags and begin excavation(Which means to dig out).

The paleontologist will dig a trench around the bone (shown intop right of page) so that it is elevated on a dirt pedestal.

The dirt and bone is then covered in toilet paper to protect itfrom the wet plaster cast that will shortly be wrapped around

it.

The paleontologist then soaks burlap in water (damp burlapabsorbs the plaster more efficiently) and mixes the Plaster of

Paris. After ringing out the wet burlap it is dipped into the

plaster and wrapped around the specimen in a crisscross

pattern.

Once the jacket dries the specimen is flipped over, examinedfor exposed bone, and removed from the site.

A Paleontologist digs the trench aroun

mammoth tusk.

A paleontologist dips burlap

into the Plaster of Paris.

Fun Facts This low-tech method has been used for over 100

years and we are yet to find a better way to remov

fossils!

For fossils that are 1cm or smaller in size (Microfoswe use a screen washer to find them. The two wat

troughs seen in the back of the Fossil Discovery Ce

building are used for that process.

The Dig Diorama An Excavation Model

Next Exhibit: Display Cabinets

A casted fossil dries!


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ate of the Fairmead site: 550,000 780,000 yr. B.P.

Fossil Display Cabinets and Signage

Paleomagnetism: Two samples from the site were taken to thePaleomagnetism Laboratory of UC Davis and run through a

cryogenic magnetometer. The results showed that the fossils

were deposited during the Brunhes normal polarity epoch

(around 780,000 the present).

We discovered Tetrameryx (Antelope) bones that were onlyknown to exist in the bay area during the Irvingtonian time

period.

When you find large herbivore bones that are from theRancholabrean time period you usually find bison along with

them. We dont find any bison at the Fairmead Site.

About the exhibit Fossils are exceptionally rare because it takes very

specific circumstances to allow for fossilization. The

animal needs to be covered in sediment as soon as

possible unless it is frozen or dies in an anoxic (oxyg

free) environment.

The display cases show a variety of fossils frompetrified wood and amber (fossilized tree sap), to

trilobites and coprolites (fossilized dung).

Trace fossils, such as burrows, carvings, footprints, afeeding marks, give us clues to what the organism d

while it was alive!

The first two glass cases contain fossils that are notfrom our site. The third glass case contains bones th

were found at our site. On the top shelf you might

able to find a bone that has a hole in it. This is the h

bone of a horse and that hole just might have been

made by the strong jaws of a Dire Wolf.

The fourth case illustrates some of the tools that areused to preserve the fossils.

t the Fairmead site? The Fairmead Landfill is situated on what used to be the alluvial

fan of the Chowchilla River. An alluvial fan is where a fast

flowing river or stream flattens, slows, and spreads.

The seasonal flooding of the river would have left behindtemporary watering holes that would attract many animals and

predators. The next season of flooding would then cover the

bones with sediment.

An alluvial fan

Geologic Time Scale

Next Exhibit: The Evolution of the Horse

erms you might want to know:

r. B.P.: Years before present

vingtonian: A time period specific to North America from 1.8 million 240,000 yr. B.P.

ancholabrean: A time period specific to North America from 240,000 11,000 yr. B.P.

Dinos

First H


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Fun Fact: Horses share common ancestry with Rhinoceroses

Terms you might want to know:

*mya: Million years ago

Browser: An herbivore that feeds on high growing plants, such as shrubs.

Grazer: An herbivore that feeds on grass or other low vegetation.

Evolution of the Horse Display

What does vestigial(Ves-ti-jee-ul) mean? If you look at the bones that are on the ground on the ri

side of the horse display you should see a modern horse

foot (The only light colored bone). The two bones on th

back of the foot are actually remnants of the outer toe

of its ancestors!

These toe bones are considered vestigial because theyhave lost most if not all of their ancestral function as toe

More examples of vestigiality:

The blind mole rat has eyes that are covered by skin Whales and other cetaceans (mammals adapted to aqua

life) have leg bones!

Humans have underdeveloped ear muscles that dontallow us the mobility of other animals.

Human goose bumps are vestigial. Their originalfunction was to raise the hair to make us larger so we

could scare off predators.

Flightless birds like emus, penguins, and ostriches still hawings.

During the late Eocene the climate in North America becamemuch drier and grass began to evolve! This would mean that

the forests were giving way to flatlands and prairies. Because

of thhis environmental change the horse (now Mesohippus)

evolved to have only 3 toes. It walked predominantly on its

middle toe. This horse still had soft feet.

Motivated by the new hard ground and the need to outrunpredators (cant hide in the prairies) the horses foot began to

change into a hoof. The hoof is made out of keratin, the same

protein that makes up our hair and nails.

Many other changes were taking place as well. The legs of thehorse were getting longer enabling it to run faster, their neck

was getting longer to make it easier to reach the grass, and the

Next Exhibit: Fossil Display Cabinets and Skulls

The first horse, Hyracotherium (52 32 mya)

Horse foot evolution

The Hyracotherium (52 32 mya) is the earliest animal to showhorse-like anatomy and is shown in the upper right hand

corner of the exhibit. Hyracotherium bones are found mainly

in Wyoming, and as you can see it did not have a hoof yet and

his teeth were small and rigid. The environment at the time

was like that of a tropical rainforest.

The early Hyracotherium was a browser because grass did notexist yet!


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1. Astragalus2. Atlas3. Axis Vertebra4. Calcaneum Caniniform Shaped like a

canine tooth

5. Carpals6. Cervical Vertebra7. Cranium8. Cuboid9. Dentary/Mandible

Dentitian Arrangement of

Developing Teeth in the mouth

10.Fibula11.Humerus12.Incisors13.Lumbar Vertebra14.Maxilla15.Metacarpal16.Metatarsal Metapodial Referring to

either the metatarsals or the

metacarpals

Molariforms Having the formof a molar tooth

Neurocranium The part ofthe skull that houses the brain

17.Occiptal Condyle18.Pelvis19.Philanges20.Radius21.Scapula22.Tarsals23.ThoracicVertebra24.Tibia25.UlnaThe radius/ulna (forearm) and

tibia/fibula (shin) bones of a horse

fused together. The wolf compari

shows the difference.

You may find the following diagram helpful when viewing the bones

displayed in the cases.

The names of the bones are listed alphabetically and the numberscorrespond to their location on the horse.

*The bones are still located in similar places on the other mammals (#4 is

the horses heel bone and #5 is the horses wrist).

Fossil Display Cabinets

Wolfs Shin

Wolfs

Forearm

Refer to the next page for Information on the

replica skulls on top of the cabinets


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Fossil Display Cabinets (cont.)

Why do the horse and the Camelops skull look sosimilar? Interestingly enough, the horse and the camel

arent very closely related. A rhinoceros is more

closely related to a horse than a camel is!

The similarities in the skull that you see are duewhat is called convergent evolution. This means

that two organisms (i.e. the horse and the came

developed similar traits even though they are fr

different lineages. They developed these traits

because they both shared similar environmenta

challenges.

Pill Bug Pill Millipede

Duck Platypus

Mammal

Bird

Woodlou

se

Lizard

Snake

Brown SnakeGlass Lizard

More examples of convergent evolution:

Predator Skulls

Dire Wolf

Carnivore

The highlighted area onthe back of the dire

wolfs skull is called the

sagittal crest. This is

where the jaw muscles

will attach giving them amore powerful bite!

Smilodon

Carnivore

The saber-toothed cat(nottiger) could open its

mouth at a 120 degree

angle.

The inside edge of theirlarge teeth (highlighted

yellow) is serrated, like a

steak-knife.

Defense

Beak

Legless

Browser

Modern-day Camel

The skull on the top leftof the cabinets is a

Camelops (Western

Camel) skull. The picture

on the left is modern day

camel. You can see how

much the camel has

changed!

Grazer

Horse

Sitting to the right of theCamelops skull is the

skull of a Pleistocene

horse.

Next Exhibit:

The Lab

-The skulls located on the top of the shelves are all

replicas but the bones inside the display cases are real.

-A replica is an exactcopy of the original.


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The Laboratory

Fun Fact: Most of the lab work is done by volunteers! If you share our

interest in past life feel free to fill out a volunteer application at the front

desk.

Fossils that come in from the dig sight are cleaned and prepared for

exhibit here at the lab.

Common tools used to work on specimens

Once the fossils are removed from the dig sight they are

moved to a safe location and eventually end up here at the

laboratory.

The larger fossils are usually still encased in the burlap and

plaster cast which is carefully removed.

Once the cast has been removed the lab worker will use

dental picks to slowly expose the bone and a paint brush is

Loose dirt form the landfill is run through a screen washer

and the remaining sediment is closely inspected for

microfossils like small rodent, reptile, and amphibian bones.

Microfossils are very important because small burrowing

rodents, snakes, and frogs do not migrate making them a

good environmental indicator.

How are replicas made?A clay bed is built around the

fossil

Liquid Rubber

is painted atop

the bone

The rubber iscovered with

hard plastic

Once dry it is

removed and steps

1-4 are done for the

other half.

Next Exhibit: Mammoth

Skull

1

2

3

4

The two halves are then put

together and filled with a resin.5

A microfossil claw


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The Columbian Mammoth Skull

In 1914 A Paleontologist named Othenio Abel theorized

that dwarf elephant skulls found in Cyprus and Sicily

might have been the influence for the Cyclops myth. If a

Greek farmer were to stumble upon one of these skulls it

would be very easy to confuse the sinus cavity for a

single, large eye.

Incorrect

Correct

Dwarf elephant skull interpretations

Shark Tooth Fossils

Europe: Known as Glossopetrae

(Petrified snakes tongue), and they

grew naturally in the ground.

Malta: In 1768 they arelisted as an

available medicine in the pharmacy of

Santo Spirito to cure poisoning.Japan: Believed to be the thumbnails of

Tengu Man, a mountain goblin.

llr

Ammonite Fossils

Folklore

Northern England: Known as the

petrified remains of snakes that were

turned to stone and beheaded so an

abbey could be built in their stead.

Southern England: A British virgin who

lived in the woods turned the snakes to

stone. In other areas they were

thought to be fairies first turned to

snakes, then stone.(Extinct Mollusk)

About the Exhibit Just like humans, elephants and mammoths can be ri

or left handed. The tusk that the elephant or mamm

used more often is called the Master Tusk.

See if you can figure out what tusk the mammoth in fof you might have preferred.

In most humans the left side of the brain controls finmotor skills like hand movement, and because eachbrain hemisphere controls opposite sides of the body

have more right-handed than left-handed people.

Handedness TheoryElephant brain location

Next Exhibit: Mosasau

Woolly Mammoth head preserved in permafros

Fun Fact: This replica skull used to hang from the ceiling.


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Mosasaur Exhibit

A hunting Mosasaur

We find very fewdinosaurs in California because almost all

of the state was covered in ocean water when they were

alive! The rare exception is probably because a dinosaur

was washed out to sea after drowning in a river.

We do find Mosasaur bones in California because this

reptile was adapted to life at sea.

Mosais Latin for Meuse Riverand

Saurosis Greek for Lizard

erms you might want to know:

inosaurs: Potentially warm blooded and walked with their legs directly

eneath them

eptiles: Cold blooded and have splayed out legs.Vs.

California During the time of the Dinosaurs

Shark Tooth Hill: A spectacular amount of Miocene shark

teeth and marine mammals are buried in the hills of

Bakersfield, including Megalodon teeth!

Fossil Reef Park: The remnant of an 18,000,000 year old

tropical shell reef is located in Orange County.

There was widespread volcanism in California because the

Sierra Nevada was beginning to form during the time of

the dinosaurs. Two huge plates crashed into each other

and one went below the other.

About the Exhibit The Mosasaur breathed air and had a double-hinged

that allowed it to eat prey that was larger than its hea

This is one reason why it is considered to be the snak

closest ancestor.

Ammonites were the Mosasaurs favorite prey.

A Mosasaur (Tylosaurus Proriger) and a School Bus

In 1918 a Mosasaur was found with the remains of aPlesiosaur in its stomach!

The largest of the Mosasaur family is the TylosaurusProriger, shown in the image above.

The first Mosasaur found was in the Netherlands in1764. During the French Revolutionary war the Frenc

occupied the Netherlands and supposedlybought the

fossil for 600 bottles of wine and took it back to Paris

Fun Facts

Next Exhibit: The Pond


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Self-Guided Tour of the Fossil Discovery Center

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