Transcript Lecture 1 introduction-2011

双语教学课程
Bilingual teaching program
Lecture notes for
Paleoecology
Instructor: Hong HUA
（华 洪）
Email: [email protected]
Office: Room 430, Geological building
Scientific Method
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When solving problems scientifically we follow a series of steps
to avoid wasting time, effort, and resources. These steps
include:
1. Defining the ________ (may include research or observation)
2. Stating a ____________ (explanation of observation; must be
able to be tested)
3. _________ the hypothesis (involves measurement of one
variable at a time)
4. Analyzing the _________ (data organized in graphs, tables,
and charts)
5. Drawing _____________ (returning to step #2 as needed)
***This is not a rigid, step-by-step outline.***
Schedule of Topics
Topic
Introduction
The Earth as a system
How Real is Global Warming?
Cultural Responses to Climate Change:
What we have learnt from the Holocene
Gigantism & Dwarfism:
Thoeries about biogeography
The modern-Day Mass Extinction:
Lessons from the past
Invasive Species:
What’s the Problem
All things are not equally nice to eat:
Evolutionary Patterns
The Panda’s thumb:
Functional morphology
Trace Fossils :
Reconstructing Animal Behavior
Evolutionary Paleoecology
Examinations and Grading:
Grading: 1 tests at 70 points plus 1 presentations
at 30 points
Presentation will be evaluated by the instructor
and by the students:20 points By Instructor and 10
points by Average of student evaluations
Final examination:
l Writing test for 3 hours;
l Open to textbooks, dictionary and any other
material.
l Questions and answer are in English
Topic 1
Introduction
• 1. What is Paleoecology?
• 2. The data base in paleoecology
• 3. The operational base in
paleoecology
• 4. The nature of the fossil record
Study of fossils
What? What are fossils?
Morphological paleontology
When? When did a particular fossil live?
Stratigraphical paleontology
Whence(从何处来) and whither(到何处去)? in other
words, what were the ancestors of a particular fossil
and what were its descendants?
Evolutionary paleontology
 How and where? How and where animals
and plants lived in the past ?
Paleoecology
岩石地层学
古环境学
地史学
化石
古生物学
生物地层学
古生态学
古生物钟
地质年代学
古生物地理学
进化生物学
生物化石在地质学科多方面的运用
1. What is Paleoecology?
Ecology is the study of the interactions of
organisms with one another and with the
physical environment
Paleoecology is the study of the
environmental relationships of organisms
in the geological past
• “ecology of the past” where our
understanding of the “present is the key
to understand the past”
• Theory = paleoecology is the
understanding of relationships between
past organism and the environment in
which they lived
• Practice = paleoecology is the practice of
reconstruction of past environments
Two dominant subject areas in
paleoecology
●The study of organism-environment
interactions
● The study of the more strictly biological
attributes of the organisms —
their individual life histories,
their interactions with one another,
and their integration into communities(群
落)
Levels of ecological
organization and
examples of the
kinds of questions
asked by ecologists
working at each
level
Individuals
Physiological ecology
Behavioral ecology
Population
• Study the factors influencing population
structure and process
Adaptation
Extinction
Distribution
abundance
population growth
interaction
• Predation
• Parasitism
• competition
How do Ecology and Paleoecology differ
Can we observe the actual ecosystem?
Ecological study = yes, Paleoecological study = no
Can we select the organism and / or community for study?
Ecological study = yes, Paleoecological study = only
sometimes
Are our observations based upon repeatable experiments?
Ecological study = yes, Paleoecological study = no
Do our studies operate within a defined timescale and
space?
Ecological study = yes, Paleoecological study = no
Evolution
Biogeography
Physical
environment
Biota
Diagenesis
Rock facies
Ecosystem
Causal influence
Palaeoecosystem
Causal relationships in biology and geology pertinent to
ecology and paleoecology
What are some problems inherent in
paleoecology reconstruction?
One of the major limitations of the study of
paleoecology:
Not all species are preserved as
fossils
The Biocoenosis (life assemblage)
does not equal the Thanatocoenosis
(death assemblage)
(1) What we don't see may be as important
as what we do: Not every creature was
fossilized
(2)Fossil beds are composites of fossils
(3)The older the material, the more likely it
was modified, or destroyed by geological
events or biological intrusions
(4)At best you are sampling just a portion of
what existed
A lot of assumptions must be made
given the paucity( 缺 乏 ) of data
available in order for paleoecologists
to generate ecosystems of the past.
They must assume:
The ecological relationships we use today to
describe system dynamics are those that
held in the past
Trophic dynamics
energy flow transfers
competition & predation
parasitism and so on
where common controlling determinants of
ecosystem functioning
We have no real reason to doubt this at this
time
That animal, plants & microbes
had more or less the same
environmental habitats and to
an extent niches as those
today - fish live in water etc
Since all that is left generally is
the morphology of bones, pollen，
wood etc. that these
morphological adaptations to
environment fit the pattern
existent today
what is the importance of
paleoecological study for ecologists?
It tells us how we got to where
we are today
It shows us the range of natural
variation of communities and
climates
It gives us hints of where we
might be headed in the future,
especially during a period of
potentially rapidly changing
climate
• 1. What is Paleoecology?
• 2. The data base in paleoecology
• 3. The operational base in
paleoecology
• 4. The nature of the fossil record
Paleoenvironmental reconstruction
depends on three ingredients:
 a well-established stratigraphic
framework
 good taxonomy
 a comprehensive ecologic background
● The stratigraphic setting provides the
spatial and temporal relationships(时空关系)
for the comparison of fossils within geologic
history
● The basic data of paleoecology are the
fossils, adequately identified and correctly
positioned within the stratigraphic framework
The necessary ecology（常规生态学）
consists of an understanding of
 the ways in which living organisms function
within their ecosystem;
 how their morphology and physiology is
adaptive to their conditions of life;
 the ways in which they may interact with
one another;
 and the ways in which they may modify
their life history to fit the environment
l At one end of the spectrum general
ecologic "laws" developed inductively
from the living world are applied
deductively to the fossil record
l At the other end of the spectrum the
present day significance of a particular
species or morphologic feature is
applied to the same species or biotic
characteristic in the fossil record
• 1. What is Paleoecology?
• 2. The data base in paleoecology
• 3. The operational base in
paleoecology
• 4. The nature of the fossil record
The operational base in paleoecology
uniformitarianism(均变论)
analogy(同功原理)
simplicity(简化法) or
Parsimony
Uniformitarianism
Hutton (1726-1797)
Lyell (1797-1875)
• James Hutton, Scottish farmer, physician, and geologist; father of
geology; published “The Theory of the Earth” (1785)
• Charles Lyell, English geologist, published “Principles of Geology”
(1830-1833)
• “The past history of our globe must be explained by what can be
seen to be happening now”
• “The present is the key to the past” (Sir Archibald Geike, 18351924)
• Giving enough time, modern Earth processes were capable of
having produced the record of the past
• Implies deep time
Uniformitarianism can be classified as
either substantive or methodological (Gould,
1965).

Substantive uniformitarianism （实质均
变论） implies that the materials, conditions, and
rates of processes during earth history have
remained constant
 Methodological uniformitarianism (方
法均变论) implies that the laws of nature (such
as gravity, the properties of fluid flow, and
thermodynamics) have been constant in their
operation through geologic time
Four Meanings of Uniformitarianism
• Methodological
– Uniformity of Law: Foundation of historical
science
– Uniformity of Process: Actualism(现实主义)
• Substantive
– Uniformity of Rate and magnitude: Gradualism
(Things do change, but at constant rate)
– Uniformity of Condition: nondirectionism
(Things do not change; or the Earth system
has been maintaining the same equilibrium
state)
Catastrophism
Cuvier (1769-1832)
Brongniart (1770-1847)
• Baron Georges Leopold Cuvier (1769-1832) and Alexander
Brongniart (1770-1847)
• Studied fossils in the Paris Basin
• Dramatic changes in successive fossil assemblages
• Believed that these changes were caused by total extinction resulted
from catastrophes akin to the Noachian Deluge, followed by
successive creations of new species
• We now know that these abrupt changes are largely due to
unconformities or missing record
• Catastrophism has not been totally abandoned; it is particularly
instructive in later studies on mass extinctions
Analogy (or actuopaleontology
（实证古生物学）) involves the application of
modern organismic features to ancient
organisms.
This principle may be applied to :
individuals (with regard to form and function)
community
structure
(species
diversity,
organizational and trophic structure（营养结构）
and population dynamics (response to timeindependent environmental factors),
and is inferred to represent response to timeindependent environmental forces
Whenever we find, in two forms of
life that are unrelated to each other,
a similarity of form or of behavior
patterns which relates to more than
a few minor details, we assume it
to be caused by parallel adaptation
to the same life-preserving
function
章鱼
人类
Simplicity or Parsimony
Principle of simplicity: everything else being equal,
the best explanation is the simplest one
Simplicity in this sense is that the most probable
explanation is generally the one with the fewest
steps from cause through intermediate causes and
effects to the final result
Ockham's Razor
This simplifying procedure should be
valid in paleoecology because it is
exactly that used in ecology, and in
science in general
 It saves us from the despair of
attempting to derive from the limited
paleontologic data an explanation
incorporating
the
myriad
of
environmental parameters
• 1. What is Paleoecology?
• 2. The data base in paleoecology
• 3. The operational base in
paleoecology
• 4. The nature of the fossil record
A fossil assemblage may be only a
small and biased representation of the
original community
Destruction by various processes after
death of the organism, a potential fossil
may not be preserved
Taphonomy
(1) It helps in understanding the relationship of
the fossil assemblage to the original
community and thus allows to some extent
the reconstruction of the community
(2) Recognition of taphonomic processes that
have formed the fossil assemblage provides
insight into the depositional and
postdepositional environment
Subsidiary topics within taphonomy are necrolysis
（尸积学）, which deals with the decomposition of
the organism upon death,
biostratinomy（化石产生学）, which deals with the
sedimentational history of the fossil, and fossil
diagenesis, which deals with chemical and
mechanical alteration of the fossil between the time
of its burial and collection
During each of these stages of the
post-mortem history, mechanical,
chemical, and biological processes
are reshaping the original community
Two opposing views on processes
that form from the original
community the assemblage of
fossils
One is that a fossil assemblage
accumulates slowly through the yearby-year preservation of some fraction
of the community
Thus the assemblage represents a
time-averaged sampling of a
sequence of communities over a
period of years and of perhaps a
considerable range of environments
(Fürsich, 1978)
The opposing view is that preservation is in
general so poor, the fossil record is much
more likely the result of occasional chance
preservation of an individual community
Thus an assemblage may be a fairly
reasonable representation of the community
existing during a short interval rather than
the accumulation of meager sampling
during a longer time interval
• 1. What is Paleoecology?
• 2. The data base in paleoecology
• 3. The operational base in
paleoecology
• 4. The nature of the fossil record
Text books and references:
陈源仁,1992. 生态地层学原理. 北京:地质出版社
孙儒泳，李 博等, 1993. 普通生态学.北京:高等教育出版社.
杨式溥, 1983. 古生态学及遗迹化石学. 武汉地质学院古生物教
研室.
殷鸿福等,1988. 中国古生物地理学.武汉:中国地质大学出版社
Boucot, A.J., 1981, Principles of
Academic Press.
Benthic Marine paleocology,
Dodd, J.R. and Stanton, R.J., 1981, Paleoecology, Concepts
and Applications. John Wiley and Sons.
Allmon W. D., Bottjer D. J.,2001. Evolutionary paleoecologyThe ecological context of macroevolutionary change.New York:
Columbia University Press.