Population controls Natural selection
Individual Interactions Interactions
Interspecific interactions interactions between individuals from two different species
Why study interspecific interactions? Why
hey are important for p
Lecture 9: Natural Selection II: Darwin and Wallaces solution to the problem of adaptation Wallaces
III. The Theory of Evolution by Natural Selection E. Questions Answered by Natural Selection
The Theory of Natural Selection answered several The nagging q
Lecture 10: Mendelian Genetics, Part 1 Mendelian
What well cover in the next few lectures
HEREDITY is the study of how the genetic composition of an organism (its _GENOTYPE_) and the environment _GENOTYPE_ and influence its the physical appearance (its _P
Lecture 12-13: Population Genetics Genetics
I. From Transmission Genetics to Population Genetics I.
Natural Selection requires variation among individuals. Where does this variation come from, and how is it maintained? this
1. ALL new genetic variation co
I. The Hardy-Weinberg Equilibrium I.
In lab this week, you will compare the expected genotype frequencies (calculated In from the H-W equation) to the observed genotype frequencies (obtained by counting actual genotypes) to see if the population is in H-W
Lecture 15: Natural Selection Lecture
II. Causes of Evolution
So far. So Analysis of effects of. A. mutation B. gene flow between populations C. finite population size/genetic drift D. nonrandom mating E. Now its time to analyze the types
Testing the alternatives: What happens when you remove Ulva?
Ulva removed % cover of Gigartina control tolerance
Time since disturbance
The food chain and web abstractions
Trophic level: all the organisms whose energy source has pa
Function and value of Biodiversity
Biodiversity is under threat as we are in the midst of a 6th mass extinction.
Actual data on local species loss (or gain) in the UK
Introduction of new species
(Thomas et al 2004 Science)
Biodiversity whats it good for
Lecture 16: Mendelian Genetics 2 Mendelian
II. Mendelian Genetics B. What Mendel did, 5. Law of Assortment
Mendels next experiment: Mendels Crossing peas that differed in two charactersseed shape and seed color. and This is a _DIHYBRID_cross (two traits t
Trophic cascades are an example of top-down regulation of community composition and plant biomass: Bottom up _ _)
Both removing top predators and adding nutrients can alter plant biomass for EXAMPLE: Piscivore(large fish)
Biodiversity: The 3 BIG questions
1. Maintenance - what allows the coexistence of so many species in one habitat? 2. Origin - What causes large scale biogeographic patterns in diversity? 3. Function - Why care about biodiversity?
Maintenance of diversity:
Ecological and evolutionary consequences of human activities
Humans as the ultimate top predators
Trophy fishing (1950-2009)
In a review of 34 studies that tracked 29 species across 40 different geographic systems, harvested and hunted p
So how do we get to estimate things like r?
Demography: a study of the vital statistics (birth, death) of a population and how they vary with age Life table: vital statistics of a cohort (group of individuals born about the same time)
Remember Darwins att
1000 800 600 400 200 0 0
r = 0.1 r = 0.2 r = 0.3 r = -0.3 r=0
Intuitively, a population increases in size when its birth rate exceeds its death rate: b >dor when r is positive; r = 0 when b=d r >
What is competition? When individuals use a shared resource that is in short supply (not enough resource for all) Results in decreased rates of growth, survival or reproduction that alter population growth rates.
If you would like to request a regrade, please 1) First look over the answer key (there are two typos on the v. B key questions 4 and 18, where the wrong letter is given as the correct answer DO NOT ask for a regrade for these the exams were
What is a community? Your text: the species that live and interact within an area, P. 398. It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, a
Lecture 26: Sexual Selection and Speciation and
I. Sexual Selection & Speciation
Many organisms recognize members of their own species using highly specific Many a. courtship behaviors b. songs (birds, insects) These evolve primarily by _sexual selection
Lecture 27-28: A Brief History of Life on Earth History
Outline of Lectures 27-28
I. How do we learn about Ancient Events? I. II. How Have Earths Continents and Climates Changed over Time?
A. Continental Drift: Earths continents have moved B. Atmospheric
Lectures 24-25 and Discussion 7: Lectures Species & Speciation Species
There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one; and that, whilst this planet has gone cycling on accordin
_ Lectures 24-26 and Discussion 7: SPECIES & SPECIATION _ I. DEFINITIONS OF SPECIES 1. The Biological Species Concept: A species consists of groups of actually, or potentially, interbreeding natural populations of organisms that are reproductively isolate
Discussion 4: An early challenge for Darwin: How does cooperation evolve by natural selection? natural
I. Why is cooperation hard to explain? I.
I. Why is cooperation hard to explain?
Cooperation appears to involve _alturism_: _alturism_: _alturism_is the
Are you getting it? (think about these and write an answer while we are waiting to get started): 1. At what latitude are the worlds deserts and rainforests?
2. Can you explain why they are located there ?
Todays Discussion: How many species are there on E
P(eaten)=P(detection)+P(capture)+ P(consumption) Cryptic coloration
ColorChange: Can occur on a long timescale (months). Or rapidly
Costs of being cryptic: tied to particular habitats:
Decorator crabs take it with them but still P(eaten)=P(detection)+P(ca
The niche - a preliminary definition:
The set of environmental conditions under which organisms can grow and reproduce (salinity, temperature, humidity, etc)
Example: The fundamental niche of the 7-spine shrimp
Well talk later about how the niche may be m
Greatest Warming Is in the North, but Biggest Impact on Life Is in the Tropics, New Research Shows ScienceDaily (Oct. 7, 2010) In recent decades documented biological changes in the far Northern Hemisphere have been attributed to global warming, changes f