HUNTING FOR FOSSILS IN LOUISIANA

The Mission of theThe Mission of theLSU Museum of Natural ScienceLSU Museum of Natural Science

Acquisition,Acquisition, Preservation, andPreservation, and StudyStudy

of research collections to generate knowledge of:of research collections to generate knowledge of:

Regional and global biodiversity,Regional and global biodiversity, Geological history, andGeological history, and Human history and prehistoryHuman history and prehistory

for the benefit of the people of the state, the nation, and the world.for the benefit of the people of the state, the nation, and the world.

Divisions of the LSU MNSDivisions of the LSU MNS

7 main fields of RESEARCH7 main fields of RESEARCH Ornithology (Birds)Ornithology (Birds) GeneticsGenetics Ichthyology (Fishes)Ichthyology (Fishes) MammalogyMammalogy Herpetology (Reptiles and Amphibians)Herpetology (Reptiles and Amphibians) PaleontologyPaleontology Anthropology (Archaeology and Ethnography)Anthropology (Archaeology and Ethnography)

EDUCATIONEDUCATION

1.1.THE PALEONTOLOGY THE PALEONTOLOGY COLLECTIONSCOLLECTIONS

What is palynology?What is palynology?Palynomorphs =

- both plant and animal structures

- microscopic in size (from about 5 µm to about 500 µm)

- made of compounds that are highly resistant to decay

- abundant in most sediments and sedimentary rocks

- can be extracted by chemical processing (acids digestion & sieving)

Spores Pollen grains Dinoflagellate cysts Acritarchs Leiospheres

Invertebrate Paleontology: PalynologyInvertebrate Paleontology: PalynologyDr. Sophie Warny

* Biostratigraphy and geochronology: - correlate strata - determine the relative age of a bed or formation

What is it used for?What is it used for?

* Palaeoecology and climate change: - used to reconstruct past vegetation (land),

hence palaeoclimatic conditions- used to infer past environmental conditions (marine)

* Criminology (forensic palynology)

* Archaeology (past agriculture)

* Commercial (melisopalynology, culture prediction)

* Medical field (allergies)

Collections:

- Over 17,000 specimens from over 1000 localities with emphasis on Louisiana. 

Research statement: Dr. Schiebout's focus is on:

Paleoecology

Biostratigraphy and paleogeography of southern North America and China in the Tertiary

Early and middle Tertiary mammals

The Cretaceous-Tertiary and Paleocene-Eocene transition

Louisiana fossil vertebrates, particularly in the Miocene

Vertebrate PaleontologyVertebrate Paleontology

Dr. Judith Schiebout

Large collection of middle Tertiary mammals from the Fort Polk region

Dr. Schiebout excavates the lower jaw of 13.5 million year old

herbivore at Fort Polk.

Large collection of Tertiary fossils including this whale:

Vertebrae and ribs of the Eocene whale Basilosaurus at Montgomery Landing, Louisiana. The Museum holds the front 1/3 of the skeleton including one of the

most complete skulls known for this whale.

18 meters (60 feet) in length

Large collection of Tertiary mammals from Tunica Hills,

such as early elephant, rhino, hedgehog and camel relatives.

Also: Dr. Ting holding an early Pliocene(Ice age) mastodon tusk and palate from the Tunica

Hills.

Allosaurus in Howe-Russell building

The biggest, most abundant meat-eater during the late Jurassic period in America, about 150 million years ago.

It probably preyed upon large, plant-eating dinosaurs,like iguanodons.

The allosaur¹s serrated teeth, while smaller than those of theT. rex, were as capable of tearing free large quantities of meat.

-walked on two powerful legs-massive tail-short arms with 3-fingered hands-sharp claws up to 6 inches long-38 feet long and 16.5 feet tall-weighed about 1400 kg-3-ft long skull-sharp, serrated teeth 2 to 4’’ long

Goals:

- help you

identify some

of the

fossils

- describe

the history

of their

journey

2. ACTIVITY: 2. ACTIVITY: HUNTING FOR FOSSILS IN LAHUNTING FOR FOSSILS IN LA

1 Gravel can be found in many places in Louisiana

2 It occurs naturally in stream and river banks

3 Gravel is just a loose mixture of rock fragments

4 We rarely wonder where it came from…

5 We don’t often sit down and look for unusual shapes or colors

6 But… LA gravel is made up of rocks formed millions of years ago

7 On the sea bottom

8 If we look closely, we can often find distinct impressions

of ancient marine life

- The earth was formed approximately 4,600 million years ago.

- Geologists have divided the earth’s history into intervals

- The period during which the fossils found in Louisiana gravels lived was between 408 and 330

million years ago.

- The fossils in the Louisiana gravels lived during part of the Paleozoic Era, in the Silurian, Devonian, and Mississippian Periods.

- Study rocks -> in what environment sediments were deposited.

-> Recognize past rivers, beaches, deltas, inshore/offshore trends.

- Studies of Paleozoic rocks show that the North America of those times was far from that of today (it was covered by a shallow sea).

This is a scene of how the sea bottom may have looked at this time.

In this sea, life proliferated with coral reefs, fields of

sea lilies, shellfish,

moss-like bryozoans, insect-like trilobites and other

animals and plants.

How did these fossils, buried

hundreds of millions of years ago in

the North, arrived as gravels in

Louisiana today?- Buried rocks uplifed

- Weathered and broken up (erosion) by wind, water, and ice.

- Transported by glaciers between 1.8 and 10,000 years ago (Pleistocene) as the earth underwent a series of glaciation.

- At these times, ice covered much of North America, large volumes of rock were eroded.

- Some of the Paleozoic rock was broken up by ice.

- Then transported south to Louisiana by rivers when the ice melted.

- The shape, structure, and markings of a fossil =

characteristics

- Used to classify them according to the system shown

above.

- Because Louisiana gravels contain relatively few

different types of fossils, let’s look at what each fossil

type looks like.

Paleozoic life - The marine invertebrates!

Arthropodes Insects, trilobitesBrachiopoda ShellsBryozoa Moss-like animalsCnidaria Corals (tab. & rug.)Echinodermata Starfish, sand dollarsMollusca Snails, clams

Crinoid remains preserved in

gravel are mostly hollow molds

or filled molds (casts).

Look for circular shapes with a

central hole and

fine radiating grooves.

Look also for rectangular and

columnar shapes,

sometimes stacked.

Rugose:

- solitary or colonial

- extinct group of corals

- abundant in

Ordovician/Permian

- some were a meter in length

Tabulate:

- common in gravels

- differences with rugose:

a) all colonial;

b) radiating septa reduced or

absent

c) main structure = horizontal

plate (tabulae) that looks

like ‘honeycomb’ appearance.

Bryozoans are:

- moss-like animals

- grow in fan-shaped,

branching,

or encrusting colonies.

- look somewhat like

corals;

- but, more delicately

built,

- with a fan-shaped

structure.

In gravels:

look for delicate fan

shapes.

Mollusca: Bivalva

- clams, oysters, mussels

- shells = 2 pieces (valves)

- joined by an elastic ligament

- shells:

= mirror images of each other

= ! bilateral symmetry

Difference with brachiopods:

Each valve is bilaterally

symetrical.

Mollusca: Gastropoda- soft body - a large foot enclosed in:- a single, non-chambered, coiled shell.

The shells may be shaped as a:- dome or - cone

The gravels usually contain casts of the inside coils of the gastropods.

Look for these coiled cross-sections.

Brachiopoda- shells

- attached to the sea bottom

by a fleshy stalk or pedicle.

- a hole through which this stalk

passed

- it can often be seen on the

larger of the two valves

- brachiopods always:

* have different sized valves,

* each valve is bilaterally

symmetrical.

* bivalves do not have a

pedicle hole.

Trilobites:

- extinct marine arthropods (insect-like animals) - lived on the seafloor. - they have a three-part body plan that consists of a

* cephalon (head), * a thorax, and * a pygidium (tail)

with a chitinous exoskeloton.

The thorax is fairly flexible and when preserved, the trilobites are often found curled up like modern rolly-pollies.

They are rarely found preserved in gravels.

3. FIELD TRIP: PRACTICAL DETAILS3. FIELD TRIP: PRACTICAL DETAILS

General Info& Tours

Monday-Friday 8:00 am - 4:00 pm

FREE!

SchedulingMaterialsRulesParking

…

4. MNS ACTIVITY BOOKLET4. MNS ACTIVITY BOOKLET

Activities forSelf-guided tours

The MNS book is available:- in French thanks to:… Anne-Sophie & Stanislas Dubois

- in Spanish thanks to:… Ana Morales

Learn about paleontology!

Learn aboutmastodons!

5. HANDS ON ACTIVITIES5. HANDS ON ACTIVITIES

Learn aboutthe different types of fossils