Transcript A brief HISTORY OF PALEONTOLOGY

INTRODUCTION TO
MICROPALEONTOLOGY
MICROPALEONTOLOGY
• Study of small fossils that must be studied with a
microscope.
• Taxonomically diverse & heterogeneous:
– Monerans (Bacteria)
– Protistans (small Eucarya)
– [Review 5-kingdom & 3-domain classifications]
– Parts of
• Animals (e.g., teeth, scales) and
• Plants (e.g., pollen, spores)
– Fungi (minor)
– Incertae sedis (of unknown taxonomic affinities)
MICROPALEONTOLOGY DEVELOPED FOR
PRACTICAL REASONS
• Size of some fossils requires
– microscopic equipment
– different preparation techniques
• Commercial applications in search for mineral and energy
resources
• Abundance of microfossils is high
• Small sediment samples are sufficient, e.g., well cuttings
• Rigorous quantitative analyses are possible because of abundance
• Distribution of microfossils is widespread
– Geographically
– Environmentally
– Lithologically
– Age
MICROPALEONTOLOGY DEVELOPED FOR
PRACTICAL REASONS
• Most sedimentary rocks are marine & most microfossils are
marine
• Many occur in otherwise unfossiliferous nonmarine rocks, e.g.,
pollen and spores of land plants (=palynology), ostracodes,
conchostracans, charophytes.
• Microfossils are generally excellent indicators of
– Age
– Paleoecology
– Paleoenvironments
– Paleogeography
– Thermal maturation
EXAMPLES OF TAXONOMIC DIVERSITY
• Prokaryotic Bacteria (cosmopolitan, Precambrian-Recent)
[Reading assignment in Brasier = Chapters 1-3 (copied)]
• Protoctistans (~Protista)
–
–
–
–
–
–
–
–
–
–
–
–
–
–
Dinoflagellates
Silicoflagellates
Coccolithophores
*Diatoms
Chlorophyta
Charophyta
Rhodophyta
Tintinnids
Calpionellids
*Acritarchs
Chitinozoa
Ebridians
**Radiolaria
*****Foraminifera
EXAMPLES OF TAXONOMIC DIVERSITY
• Animalia
– Micromollusks (Pteropods, tiny prosobranchs & bivalves)
– ***Ostracodes (Arthropoda)
– Conchostracans (branchiopods) (Arthropoda)
• Skeletal elements (parts)
– Spicules (Porifera & other invertebrate phyla)
– Sclerites of sea cucumbers
– ***Conodonts (Chordata)
– Scolecodonts (Annelida)
– ***Pollen & spores of Tracheophyta (vascular plants)
(palynology)
EXAMPLES OF TAXONOMIC DIVERSITY
• Megafossils that are studied exclusively microscopically
– ** Ectoprocta (= Bryozoa)
– **Graptolites
– Stromatoporoids (Porifera)
– Calcareous algae
DIVERSITY OF SKELETAL COMPOSITIONS
•
•
•
•
•
•
*Aragonite
*Calcite
*Mg-calcite
*Opalline silica
*Apatite
*Organic
– Chitin
– Cellulose
– Others
• *Arenaceous/agglutinated
• Rare minerals
– Celestite (Sr sulfate)
– Magnetite
– Rhodocrosite (sp?)
DIVERSITY OF SAMPLE PREPARATION
TECHNIQUES
• Unconsolidated sediments
– Washing & sieving
– Heavy liquid separations
– Floatation
• Consolidated/cemented sedimentary rocks
– Splitting and crushing
– Chemical solution and disaggregation (e.g., for ostracodes, etc.)
– Acid dissolution and insoluble residue analysis
– Thin section studies (e.g., fusulinids)
GEOL 3213, Micropaleontology
• Description:
– Study of selected major groups of
microfossils: their morphology,
classification, evolution, paleoecology and
biostratigraphy.
• Prerequisite:
– GEOL 2213 (History of Life), equivalent, or
permission of the instructor
GOALS














 
 
 
 
 
 
 
Survey the major and some of the minor microfossil groups
Identify major fossil groups in thin section
Prepare samples for microfossil analysis
Pick microfossils from prepared samples
Prepare micropaleontology slides for study
Recognize major kinds of microfossils isolated from matrix
Recognize a population of individuals as representing a
species, genus, etc.
Identify genera and species with suitable reference
materials
Prepare faunal lists for evaluation
Be able to use a faunal list to determine an assemblage's
age
Be able to use a faunal list to determine an assemblage's
paleoecology
Become familiar with applying the procedures of taxonomy
Be able to describe and illustrate fossils
Be able to prepare a report on a fossil assemblage
EVALUATION
•
•
•
•
•
•
•
•
Laboratory reports on fossil assemblages
Laboratory skill development
Written homework assignments
Tests:
– Test #1
– Test #2
PowerPoint Oral presentation
Class participation
Class & laboratory attendance
Final examination
TOTAL
25%
5
10
10
10
5
5
5
25
=
100%
Outline of Topics in Detail
• Lectures – see syllabus
• Laboratories – see syllabus
• ACME “Related Links” provides various files:
– Syllabus
– Powerpoint lecture files
– Assignments
END OF FILE
5 KINGDOMS
(Whittaker; Whittaker &
Margulis)
Symbiosis Theory for the
origin of eucaryotic cell
(Margulis)
Broad Cell Categories
• Prokaryotic cell evolved first:
– Small cells
– No nucleus
– No organelles (no chloroplasts, etc.)
• Eukaryotic cell evolved ~1.5 Ga ago (?2.7Ga) through symbiosis:
– Larger cells
– Has nucleus, organelles, etc.
• Chloroplasts from cyanobacteria
• Flagella from other prokaryotes
• Golgi body from other prokaryotes
• Notes:
– Debate about age of 1st appearance
– Debate about only symbiosis
Model for Symbiosis Theory for Origin of Eukaryotic cells
DOMAIN CONCEPT
• 3 Domains of Carl Woese of Univ. of Illinois (early 1990’s):
MANY MORE KINGDOMS NOW CONSIDERED
• 3 Domains of Carl Woese of Univ. of Ill.:
ARCHAEA
• Domain Archaea with 3 kingdoms:
• 2.7 Ga molecular data (Australia)
• 3.8 Ga organic matter = chemical fossils?
Methanogens
Thermophiles
Halophiles
Kingdoms vs Domains
A. The new tradition became the 5 kingdom system.
Monera
Protista
Plantae
Fungi
Animalia
But, these were polyphyletic!
B. Then, 6 (& even 8) kingdoms were proposed:
Archaebacteria
Monera
Protista
Plantae
Fungi
Animalia
C. 3-Domain system is widely accepted today
B
Domain EUKARYA
A
A
C
T
E
R
I
A
R
C
H
A
E
A
A
R
C
H
E
Z
O
A
E
U
G
L
E
N
O
Z
O
a
A
L
V
E
O
L
A
T
a
S
T
R
A
M
E
N
O
P
I
L
a
R
h
O
D
O
P
H
Y
T
A
Plantae
+ others
Fungi
Animalia
New Version of the Tree of Life
Ancestor
Domain Bacteria
Domain Archaea
Domain Eucarya
K. Archaezoa
K. Euglenozoa
K. Alveolata
Dinoflagellates
Apicomplexans
Ciliates
K. Stramenopila
Diatoms
Golden Algae
Brown Algae
Water Molds
K. Rhodophyta
K. Plantae
Chlorophyta
Tracheophyta
K. Animalia
3-Domain Classification
• Based on molecular analyses
MICROPALEONTOLOGY