What is Ecology?
Study of Organism-Environment Relations, Destruction of one organism in the environment can lead to the
destruction of other organisms
What did MacArthur’s Warbler study consist of and what was the result?
MacArthur studied ecology of five species of warblers in spruce forests in North America, Theory predicted two species with identical ecological requirements could not coexist indefinitely/ Compete with each
other thus cannot live in the same env. Indefinitely. Studies found warblers coexisted by feeding in different zones of the same tree/ Resource portioning.
Define Resource Partitioning
Multiple species use the same resource in a slightly different way or at a different time
What did Schindler’s large-scale lake experiment consist of and what were the results?
David Schindler led experiments involving additions of nutrients to entire lakes in the Experimental Lakes Area (ELA) in Ontario, Lab experiments were inconclusive so whole-lake experiments were needed. Phosphorus (P) is the main cause of eutrophication. Proof is especially obvious in the Lake 226 experiment. Phosphorus, carbon, and nitrogen added to one half, but only
carbon and nitrogen to the other half. The part of the lake with additional phosphorus turned green.
What were the 3 key points of Darwin’s Theory of Natural Selection?
-More offspring are produced each generation than can survive (than the environment can support for survival).
-Heritable variation in traits among individuals in population.
-Some individuals, because of physical or behavioral traits, have a higher chance of surviving than others in the same population/ higher fitness
What is considered to be “the substrate upon which the environment acts during the process of natural selection?”
Phenotypic Variation
Genotype + Environment = ?
Phenotype
What is an Ecotype?
Distinct form or race of a
plant or animal species
occupying a particular
habitat
What did Clausen and colleagues discover in their experiment about Variation in Widely Distributed plants?
Many plant species differ dramatically in
form from one elevation to another.
Clausen and colleagues discovered that ecotypes of Potentilla glandulosa had
adapted to their specific local environmental conditions, Distinctive ecotypes.
Evolution is the change in _
gene frequency within a population
What are the three major forms of selection and their definititons?
-Stabilizing Selection: impedes changes in population by acting against extreme phenotypes and favouring average phenotypes
-Directional Selection: leads to changes in phenotypes by favouring an extreme phenotype over other phenotypes in the
population.
-Disruptive Selection: creates bimodal
distributions by favouring two or more extreme phenotypes over the average phenotype in a population.
Which type of selection was exhibited by Caroll and Boyd’s Soapberry Bug experiment?
Directional Selection (beaks changed according to fruit size, extreme phenotypes of longer beaks favoured with larger fruit)
The two main possible causes of speciation, both changing gene frequencies are:
Natural Selection and Genetic Drift
Natural selection acts on __, causing evolution within
__.
individuals, populations
Can Natural Selection determine behaviour of an individual?
Yes (Honey bee example: single gene determines whether bee is worker / forager)
What are the 3 species concepts and their definitions?
-Morphological species concept (sometimes used, mainly in paleontology): A classification of organisms belonging to the same species based on conserved morphological (anatomical) features; this concept may be useful when organisms do not reproduce sexually or are extinct and only known through fossils.
-Biological species concept (used in ecology in evolutionary biology)
Where populations of organisms able to interbreed and produce viable, fertile offspring are classified as belonging to the same biological species.
-Phylogenetic species concept defines species based upon evolutionary history andphylogenetic similarity. Increased focus on microbial organisms and increased availability of molecular methods, will likely allow this species concept to become more common over the next decade
What is Hamilton’s concept of Inclusive Fitness?
an individual’s overall fitness is determined by its survival and
reproduction plus the survival and reproduction of its relatives
(whom the individual shares genes).
an evolutionary strategy that favours the reproductive success of an organism’s relatives, even at a cost to the organism’s own survival and reproduction (ensuring survival of genes) is called what?
Kin Selection
What are the 4 main classes of social interaction and what do they mean?
Cooperation: ++
Altruism: -+
Selfishness: +-
Spite: –
Which classes of social interaction are favoured by natural selection and why?
Cooperation and Selfishness because they increase donor fitness
Adopting offspring of another individual is an example of which type of social interaction?
Altrusim
Which type of selection is heavily criticized as inconsistent with evolutionary understanding, and what does it entail?
Group selection: individual acts counter to own interest for betterment of group
What is Hamilton’s rule?
altruistic genes are favoured when the relatedness of donor and recepient times the benefit to the recipient is greater than the cost to the donor
Three major characteristics of Eusociality?
-Individuals of more than one generation living together
-Cooperative care of young
-Division of individuals into non-reproductive and reproductive
castes.
