week6lecturer1 week6lecturer2
MAKE SURE YOU HAVE ALL THE EIGHT LECTURES:
Outline important topics for review, organized by lecture (Weeks 6-9)
- Minimum 5 bullet points per lecture
- Each bullet should include topic and brief description of what you should know (e.g. mark-recapture: equation N/m=s/r, assumptions, methods of marking)
- Review lecture slides and book
- Can include figures you think are important/challenging
- No page limit
I will send you the lectures after you accept as there are too many/it is too large to upload beforehand. All lectures are based on ecology.
Welcome
to EEB 100 (part II):
Introduction to Ecology
Instructor: Alison Lipman, Ph.D. Ecology
Lecturer, Dept. of Ecology & Evolutionary Biology
Co-founder / President SELVA International
Email: alipman@ucla.edu
Office: Mira Hershey 320
Office Hours: Tuesday 12:30-2:00 or by appt.
Amazon Forest, Bolivia
My Amazon
Work…
River Turtle Conservation: Bolivia,
IUCN, SSC, Red-listing group
Wildlife Rehab
Parque Machia, Bolivia
Wild Harvested Acai,
Comunidad de Porvenir,
Bolivia
Amazon Exchange Program
Noel Kempff Mercado NP
Bolivia
Eco Education, Indigenous
Communities del Bajo Paragua
Before in LA…
Palos Verdes Blue Butterfly
Project & Habitat Mapping
Habitat Restoration: Palos Verdes,
Santa Monica Mountains
Native Plant Propagation: Palos Verdes,
Santa Monica Mountains, Theodore
Payne, Tarweed Native Plants
Bioassessment, Water Quality
Studies, Santa Monica Mountains
Now in LA…
Native Garden Coalition
California Friendly Gardens: HOWs,
EcoGardens, & Research
Fight Against Plastics
Farmer’s Markets’ Sustainability
Course Info
• Be sure to check the course website for
additional readings/videos.
• This class is not podcasted, so check posted
notes, and take your own!
– Posted notes will not contain all pics for ease of
printing and copyright.
Have a question?
**First read your syllabus!
Contact your TAs:
• Questions related to lab or grading
Email me:
• Questions about class logistics
• Appointments to meet in person (if you have a conflict with
office hours)
• Brief clarification of lecture material that your TA cannot
answer
Expect 1-2 days to receive a response, longer on weekends
Use my office hours for:
• In depth questions about material
• To come chat about ecology, conservation, etc!
Course Material / Final Exam
• Use my lecture notes as an outline.
• Refer to the textbook for more detail.
• I will follow the textbook, as long as I like it!
• Be sure to read the assigned Ecological Applications!
• All assigned videos and articles will also be included.
• I care about concepts, NOT pointless details (e.g. dates,
names, difficult terms)
Tips to help you succeed in this course
• Do readings before coming to lecture.
• Come to lecture – there will be quizzes!
• Actively take notes during lecture.
• Attend office hours – don’t wait until it’s too
late!
Classroom Courtesy
Cell phones are toxic- to the natural environment AND the learning
environment, so please turn off in lecture and discussion!
Lecture 1: Intro to Ecology
What is it? What’s it good for? Why study it?
“Spaceship Earth” (K. E. Boulding)
Earthrise is a photograph of the Earth taken by astronaut William Anders in 1968, during
the Apollo 8 mission. Nature photographer Galen Rowell declared it “the most influential
environmental photograph ever taken.”
Overview
What is Ecology?
• ECO-
– from Ancient Greek οἶκος (oikos, “house, household”)
• -LOGY
– from the Greek verb λέγειν (legein, “to speak”) the study of [a
certain subject]”
(Wiktionary)
• Ecology is the scientific study of our home/environment
Our textbook
says…
“Ecology is the study of the relationship
between organisms and their environment.”
Ecology is…
• The study of any and/or all interactions
involving organisms (life) and their
environment.
Ecology is Science
• Ecology is the science most disrespected by
the media, our government, and the public.
• Has being an ecologist become an act of
political revolution?
• Why does our government disrespect ecology
as a science?
An Interdisciplinary /
Collaborative Science
• Population Ecology
• Community Ecology
• Ecosystem Ecology
• Landscape Ecology
• Evolutionary Ecology
• Physiological Ecology
• Conservation
Ecology
• Restoration Ecology
• Human Ecology
• Plant Ecology
• Animal Ecology
• Etc.
History of Ecology
• 18th – 19th century widespread exploration to
discover and claim the natural world
– Darwin and Wallace and others travel the
world cataloging nature
– Biogeography and evolution
• 20th century – e.g., geochemical cycling,
biosphere, succession, and population
dynamics
• Today people focus more and more on human
ecology
– How are humans impacting the environment
and what can we can do to protect it?
http://environment-ecology.com/history-of-ecology/132-history-of-
ecology.html#Timeline_of_ecologists
The Human Impact
(Fig. 5.9 from Chapter 5 of Global Glacier Changes, courtesy United Nations Environment
Programme.)
The downward curve
2014, Anomalies from 20th C average
http://www.ncdc.noaa.gov/climate-monitoring/
http://www.ncdc.noaa.gov/climate-monitoring/
http://www.ncdc.noaa.gov/climate-monitoring/
http://www.ncdc.noaa.gov/climate-monitoring/
Ocean Acidification
Some local problems…
Human Impact on the Environment
• Population growth & an
ever-growing demand for
resources has led to:
– Decline in resources (land,
water, food, air, materials)
– Biodiversity loss
– Climate change
– Pollution
• We need to:
– Redefine our relationship
with nature
– Stop resource decline in
order to save life on Earth
Theoretical Ecology
• Knowledge for the sake of knowledge
• It’s interesting to know how long it takes for
detritus to rot, what soil organisms do in the soil,
why birds make such long migrations, etc.
• Background information that is the basis of
Applied Ecology.
Ecology = Conservation
But, ecology is (one of) the backbone(s) of conservation
The other backbone of
conservation:
Applied Ecology
Using science to do something real:
• How to best manage resources?
• How to restore degraded systems?
• How to conserve endangered species?
• How are we going to save life on Earth?
Applied Ecology: why I decided to become an ecologist
“Conservation” without ecology…
– Monkeys in Bolivia
– Habitat “restoration” in Los Angeles
• T. Longcore dissertation
• PVPLC & seeds
– Turtle conservation
An even worse example:
Belo Monte
& all dams in lowland areas
• Belief (not based in science):
– Dams produce “green,” carbon neutral
energy
– Dams are great!
• Truth (based in science):
– Dams can produce more greenhouse gas
emissions than coal power plants with the
same energy output.
Located on the Xingu River, main tributary of the Amazon River, the world’s third largest dam
Belo Monte
Time out for part of a movie:
Damocracy
• https://www.youtube.com/watch?v=vnM
D4e6nLms
• (-2:30, 7:15-21:05)
The point is…
• We can’t stop environmental destruction & we
can’t live sustainably, if we don’t understand how
ecosystems function.
• Until the present, decisions in our society have been
based on short-term human needs & greed/profit
• Ecology needs to become the basis of all decisions
we make:
– Economics
– Political
– Energy
– Resource use
– Infrastructure
– Etc.
Some Ecological Concepts…
Ecosystem
• Coined by Sir Arthur Tansley, an English botanist in 1935:
Ecological system: “biotic and abiotic
components considered as a whole.”
-Eugene Odum
Hierarchical Structure
© 2015 Pearson Education, Inc.
Landscape
How do variations in topography
and soils across the landscape
influence patterns of species
composition and diversity in the
different prairie communities?
Population
Is the population of this species
increasing, decreasing, or
remaining relatively constant
from year to year?
Community
How does this species interact
with other species of plants
and animals in the prairie
community?
Ecosystem
How do yearly variations in
rainfall influence the productivity
of plants in this prairie grassland
ecosystem?
Individual
What characteristics allow
the Echinacea to survive,
grow, and reproduce in the
environment of the prairie
grasslands of central North
America?
Biome
What features of geology and
regional climate determine the
transition from forest to prairie
grassland ecosystems
in North America?
Biosphere
What is the role of the grassland
biome in the global carbon cycle?
Slide 7
Scientific Method
• A powerful tool for understanding nature
• Minimizes bias through standardization &
repetition
• Empirical (verifiable by observation /
experience)
• Logical
• Conservative
• Isn’t the only way of acquiring knowledge!
© 2015 Pearson Education, Inc.
Observations
All scientific studies begin with
observations of natural phenomenon.
Question
Observations give rise to questions
that seek an explanation of the
observed phenomenon.
Hypothesis
An answer to the question is
proposed that takes the form of a
statement of cause and effect.
Predictions
Predictions that
follow from the
hypothesis must
be identified.
These
predictions
must be
testable.
Hypothesis Testing
The predictions that follow from the
hypothesis must be tested through
observations and experiments (field
and laboratory). Data from these
experiments must then be analyzed
and interpreted to determine if they
support or reject the hypothesis.
If the experiment
results agree with
the predictions,
further observations
will be made and
further hypotheses
and predictions will
be developed to
expand the scope of
the problem being
addressed.
If the experiment
results are not
consistent with
the predictions,
then the conceptual
model of how the
system works must
be reconsidered and
a new hypothesis
must be
constructed.
Slide 7
Scientific Method
1. Make observations and develop a question.
There are less turtles than before. What is
leading to their decline?
Scientific Method
2. Develop tentative answers-
hypotheses.
• Should be guided by experience & knowledge
• Must be testable (disprovable)
• Multiple working hypotheses – don’t treat your hypothesis like an only child!
3. Design an experiment to test the hypothesis
(1) Lab experiment
(2) Field Manipulative experiment
(3) Field “Natural” experiment
Scientific Method
One of my hypotheses: Human consumption is
causing a decline in local turtle populations.
Scientific Method
4. Collect data
– Qualitative/quantitative
Scientific Method
5. Analyze & interpret the data.
– Statistics
Scientific Method
6. Draw conclusions from the data.
Scientific Method
7. Determine whether results support or disprove the
hypotheses.
Scientific Method
8. If the hypotheses are consistent with predictions, conduct
additional experiments to test further, or if rejected,
construct new hypotheses (and repeat process).
Scientific Theory
“A grand scheme that relates and explains many observations
and is supported by a great deal of evidence.”
(Botkin & Keller 2011)
“An integrated set of hypotheses that together explain a
broader set of observations than any single hypothesis.”
(Smith & Smith 2015)
Can never be absolutely proven to be true.
Scientific Models
• Simplified constructs of nature
• Based on accumulated knowledge / data
• Models are useful to predict events, etc.
• Models are not perfect and need to be updated.
Uncertainty in Science
• Science is a continuous process.
• We will never have all the facts.
• We are limited to inspecting only a part of
nature because to understand, we need to
simplify.
• Human error
Ecology can be fun…
Lecture
2: Population Ecology
– Ch. 8
© 2015 Pearson Education, Inc.
Why study Population Ecology?
In order to conserve species we need to know:
Which species are threatened?
In decline?
Vulnerable to habitat change?
Cause of decline?
Which part of the population is in decline, and
why?
Is decline related to density, distribution, or range?
Problem of numbers or genetic diversity?
Are conservation efforts working?
Is a species’ population increasing, declining, or
stable?
Change in distribution?
Properties of Populations
A population is a group of individuals of the
same species that inhabit a given area and are
able to interbreed
Populations have structure
density
spacing
age distribution
Populations are dynamic, changing over time
© 2015 Pearson Education, Inc.
Organisms May Be Unitary or Modular
Unitary organisms exist as individuals
After fertilization, the zygote grows into a genetically
unique organism through a series of predictable
stages
Most animals are unitary organisms
© 2015 Pearson Education, Inc
.
Modular organism
produces more, similar modules
Most plants are modular
develop by branching, producing repeated structural
units
The fundamental unit above-ground is the leaf, with
its axillary bud and internode
Roots also show modular growth
© 2015 Pearson Education, Inc.
Organisms May Be Unitary or Modular
© 2015 Pearson Education, Inc.
Figure 8.1 Step 4 Slide 4
Axillary bud
Stem
Leaf
Node
Basic vegetative unit
Internode
Vegetative units
repeat along the stem
Vegetative branches
form from axillary buds,
and are made of
additional vegetative
units
Branch
Shoots
Roots
Whole plant in a collective of
units making up both the shoot
and root systems
© 2015 Pearson Education, Inc.
Suckers – new stems that sprout
from surface roots and may appear
to be individuals
Genet – plant produced by sexual
reproduction, a genetic individual
Ramet – module produced
asexually by a genet (a clone)
Reproduction in Plants
Stolon
.
Clones Parent
In woody plants (shrubs and trees), such as an aspen tree (Populus tremuloides),
ramets develop from root suckers. They appear to be individuals!
http://www.9news.com/story/life/2014/07/02/aspens-colorado/12051273/
Pando -105-acre clonal colony of Quaking Aspen in Utah, connected by a single root
system. At least 80,000 years ago. Some estimates as old as 1 million years.
At 6,615 tons, Pando is the heaviest living organism on earth.
To study populations of modular organisms, both
individual (genet) and module (ramet) must be
recognized
This can be challenging
molecular studies can distinguish
Ramets are often counted as individuals, and
they often function this way, but diversity must be
considered in conservation applications.
The distribution of a
population is the area over
which it occurs.
Where individuals are present
© 2015 Pearson Education, Inc.
The Distribution of a Population
Geographic Range
Encompasses all of the individuals of a species
Individuals are found in suitable habitats within that
geographic range
This range is limited by
Abiotic factors, e.g., temperature, soil moisture,
elevation
Biotic factors, e.g., predation, competition, parasitism
Giant Amazon River Turtle (Podocnemis
expansa)
© 2015 Pearson Education, Inc.
The range of the red maple is limited by temperature
in the north and drier conditions in the Midwest
Endemic Species
Ubiquitous species – geographically widespread
Endemic species – geographically restricted
many have specialized habitat requirements
Geographic Barriers
Reduce/prevent individuals colonizing new areas
bodies of water, including rivers; mountains; large
areas of unsuitable habitat such as deserts
© 2015 Pearson Education, Inc.
Genetic differences across ranges
It’s important to understand the
genetic/physiological variability across a range
E.g. Habitat restoration
• Populations divided into
subpopulations that live
in suitable habitat
patches surrounded by
unsuitable habitat
• The environment is
heterogeneous
• Spatially separated but
connected by the
movement of
individuals
Metapopulations
Worldwide
Cluster
Pine barrens
400
4000
10,000
8500
100
Locality Colony Clump
N
Swampy
Stream
20′
Region
Ocean
River
Continental
Physiographic
area
Coniferous
stump
clay bank
Distribution of
moss (Tetraphis
pellucida)
that requires
microclimates
Human altered landscapes function as
metapopulations…
1
2
3
Abundance: # of
individuals in the
pop
Population
density: # of
individual/area
Density of cell 1 =
5 ind/m2
3 kinds of
distribution…
Random
distribution: the position of one
individual is independent of another
the scattering of plant seeds by the wind can lead
to a random distribution of plants after the
seeds
germinate
© 2015 Pearson Education, Inc.
Random
Organisms are found at a regular distance
from one another
Often the result of negative interactions
among individuals such as competition
© 2015 Pearson Education, Inc.
Uniform Distribution
Uniform
Nesting Shorebirds
Acacia: uniformly spaced because of competition for water and nutrients
Individuals are found in groups
This is the most common spatial distribution and results
from a number of factors
suitable habitat or resources are found in patches
species form social groups (herds, flocks, schools)
ramets formed by asexual reproduction
© 2015 Pearson Education, Inc.
Clumped
Distributions
Clumped
Figure 8.11
© 2015 Pearson Education, Inc.
(b)
(a)
Acacia tortilis
Euclea divinorum
20 m
20 m
Spatial distributions of
individuals may be
described at multiple
spatial scales…
How to determine population size?
Population size (abundance)
population density the area occupied
Determining Density Requires Sampling
A complete count may be possible if both the
abundance and area occupied are small, or if an
area is very open so that all individuals can be seen
If an organism is sessile (attached), like a plant or coral,
sampling can be done using quadrats/ sampling units
Area is divided into subunits
# of individuals counted a random sample of subunits
Mean density X total Area = Estimate of population size
© 2015 Pearson Education, Inc.
Determining Density Requires Sampling
Depends largely on the spatial distribution of
individuals in the
population
works well if individuals have a uniform distribution
works less well with a random or clumped distribution
important to report a confidence interval or some
estimate of variation
© 2015 Pearson Education, Inc.
Determining Density Requires Sampling
10 Randomly Placed Quadrats 20 Randomly Placed Quadrats
Randomly sampling – # of samples matters!
Mark-recapture is the most commonly used
technique to measure animal population size
This method is based on
capturing a number of individuals in a population
marking them
releasing of marked individuals (M) back into the
population
after an appropriate period of time, recapture a
sample of the population
© 2015 Pearson Education, Inc.
Determining Density Requires Sampling
N -Total population
m – initially captured and marked individuals
s – captured animals on the second visit
r – the # of ind. marked on the 2nd visit
Ratio: N/M (Total pop/ Initial capture) =
s/r (2nd capture/ marked recapture)
N/m= s/r
Assumptions
1. No effect of marking on probability of recapture – tags
should not be obvious or slow the individual, or reduce
fitness in any way
2. Mixing of marked and unmarked – mix into the entire
population (how much time between sampling events)
3. Captured individuals are representative of the whole
population, not a certain age group or one sex vs another,
only weak
4. Marks are not lost
Methods of Marking
Tags
Leg bands
Pit tags
Paint
Chopping off legs
Etc.
Do these affect fitness?
© 2015 Pearson Education, Inc.
You capture and mark 80 snails by putting a small
spot of white paint on their shells. When you return
five months later, you capture 45 snails and 5 of them
have the mark. Based on these data, the population
has ________________ individuals.
A. 80
B. 128
C. 720
D. 2000
© 2015 Pearson Education, Inc.
Signs of the presence of animals include:
counts of vocalizations, such as bird song
counts of animal scat seen along a length of trail
counts of animal tracks, such as footprints in snow
Determining Density Without Direct Counts
How would you sample populations of
the giant Amazon river turtle?
Situation:
Individuals stay submerged until the nesting
season.
Individuals weigh a LOT, and are very difficult to
capture.
Individuals migrate great distances throughout
the year.
What we did…
We did mark recapture – didn’t work.
We counted ALL the nests on a sample of
nesting beaches – this worked!
Measuring turtle tracks…
Population Structure
– Age, Developmental
Stage, and Size
Abundance doesn’t provide information on the
population characteristics…
Why would you want to know the
age structure
of a population?
A population with non-overlapping generations does
not have an age structure
annual plants and some insects
A population with overlapping generations has an
age structure
reproduction is restricted to certain age classes
mortality is more common in certain age classes
Populations can be divided into three ecologically
important age classes
pre-reproductive
reproductive
post-reproductive
How long an individual is in each age class depends
on the organism’s life history
Mice, have a very short span of time between
generations
Elephants, have a very long span of time between
generations
Measures of Population Structure Include Age,
Developmental Stage, and Size
The most accurate method is to mark young
individuals in a population and follow their survival
through time
Dendrochronology – counting annual growth rings
to determine the age of a tree
Valid for dominant canopy trees, but less so for
understory trees
6 4 2 0 2 4 6
Percentage of population
6 4 2 0 2 4 6
Percentage of population
6 4 2 0 2 4 6
Percentage of population
8 8
Age
80+
75–79
70–74
65–69
60–64
55–59
50–54
45–49
40–44
35–39
30–34
25–29
20–24
15–19
10–14
Under 5
5–9
Egypt- growing United States- stable Japan- aging
Male Female Male Female Male Female
Population Structure – Age Pyramids
Plant populations, the distribution of age classes
may be highly skewed
In a forest, the tall tress can inhibit the survival of
seedlings and the growth and survival of young
trees
only when the older trees die can trees in younger
age classes access the light, water, and nutrients
they need to grow and develop
© 2015 Pearson Education, Inc.
Population Structure
Individuals Move within the Population
Dispersal is the movement of individuals in space
emigration – when individuals leave a subpopulation
immigration – when individuals enter a subpopulation
Movement of individuals is an important part of meta-
population dynamics
maintains gene flow between the subpopulations
© 2015 Pearson Education, Inc.
Passive vs. Active Dispersal
Passive dispersal (plants & animals) may include:
wind
water
gravity
animals
Active dispersal (animals)
often the young or subadults
Factors that affect dispersal
crowding, food availability/quality, temperature change
© 2015 Pearson Education, Inc.
Animals can be important dispersers of plant
seeds
Dispersed when an animal eats fruits and the seeds
they contain
Spines or hooks that attach to animal fur or bird
feathers
© 2015 Pearson Education, Inc.
Individuals Move within a Population
Individuals Move within a Population
Migration is movement of organisms that is
round-trip
zooplankton move in the water column; lower depths
during the day and the surface at night
bats leave caves at dusk, move to feeding areas,
then return at dawn
earthworms move deep into the soil for winter to
avoid freezing, then move back up in the spring
gray whales feed in the Arctic during the summer,
winter off the California coast where calves are born
© 2015 Pearson Education, Inc.
.
The gray whale
summers in the
Arctic and Bering
seas; it winters in
the Gulf of California
and the waters off
Baja California
The populations of many species of trees have
shifted north after the glaciers retreated and the
climate warmed
Population Distribution and Density Change
in Both Time and Space