Test 3 Quiz 1 Flashcards
Why are insect models so nice to study adaptations?
There is a lot of species, covering many adaptations and many habitats
Sailed around on the Beagle
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Charles Darwin
Studied the Amazon river and shipped a lot of species to the UK
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Henry Walter Bates
Studied the Amazon river and Far East, sent a letter to Darwin
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Alfred R Wallace
Lawyer/geologist friend of Darwin, invited him and another guy to present at a conference
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Charles Lyell
“Introduction of Species”
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Alfred R Wallace
“On the Origin of Species”
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Charles Darwin
“The Naturalist on the River Amazons”
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Henry Walter Bates
Comparative anatomist, slow in accepting Darwin’s theories, then his biggest supporter
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Thomas Henry Huxley
Upper class family worried about Church of England
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Charles Darwin
First to describe batesian mimicry
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Henry Walter Bates
First to study islands
Charles Darwin, Alfred R Wallace, Charles Lyell, Thomas Henry Huxley, or Henry Walter Bates
Charles Darwin
Define genotype
the sum of hereditary information
Define phenotype
the external, observable expression of the genotype
Define phenotypic plasticity
the ability of an organism to change its phenotype in response to changes in the environment
Define epigenetics
environmental factors that influence the degree of gene expression
Define selective outcome in relation to adaptation and evolution
reproduction in a population is not random, abiotic and biotic factors favor different traits, so certain individuals are more successful than others
Define evolution
differential reproductive success plus time alters ratios of genetic traits in a population
Describe stabilizing selection
favors phenotypes near the population mean; occurs in stable environments; environmental pressure on two extremes; most common type found in stable environments (in general, the most common type)
Describe directional selection
favors extreme phenotypes; occurs with abiotic or biotic selecting force; environmental pressure only on one extreme; pushes population to the other extreme
Describe disruptive selection
favors both extreme phenotypes; natural force acts on intermediate phenotypes and pushes them towards the extreme; results in a population of two or more genotypes/phenotypes; 2 selection pressures will result in three groups
Define genetic ploymorphism
A discontinuous genetic variation resulting in the occurrence of several different forms of types among the members of a single species.
Describe industrial melanism
moth living in industrial manchester England had only three phenotypes (black, gray, white) when before there was a range of colors, black also came to dominate with 95+% of the population, soot coated wood and killed lichens
Describe some effects of inbreeding depression
Reduced genetic variability, decreased fertility, loss of vigor, reduced fitness, reduce pollen and seed fertility in plants, death
Give an example of outbreeding depression
Occured with bobwhite quails when southern quails from alabama were brought in to breed with northern quails from Ohio/Illinois/Pennsylvania, but offspring from the crossings had high mortality due to lower tolerance to cold weather
Define the founder effect
Effect of starting a population in a new location with a small # of colonists, which contain only a small and often biased sample of genetic variations of the parent population; a markedly different new population may arise from migration
Describe genetic drift
Over a period of time, by probability, some genes in a population are fixed and other alleles are lost
→ Rate of genetic drift is determined by the size of the population
What are the four possible outcomes of separations of a species based on degree of geographic barriers and duration of separation?
Cline, ecotypes, geographical isolates, speciation
Define cline and give an example
Measurable, gradual change in population characteristics over a range of geography → result from a gradual physiological adaptation, behavioral and genetically in an ecological gradient
White-tailed deer are larger in the north
Define ecotype
Genetic strains of subpopulations adapted to its unique local environmental conditions; marked discontinuities, abrupt changes; also called step clines
*Each subpopulation is called an ecotype
Define geographical isolates and give an example
Formation of several subspecies due to geographical barriers
many subspecies of salamander along Appalachian Mountains in North Carolina, South Carolina, Tennessee, and Georgia
Define speciation
Evolution of reproductively separated populations
What are the three types of speciation?
allopatric, sympatric, adaptive radiation
Define allopatric speciation
Separation of a population into 2+ evolutionary units (species) by some geographic barrier that causes reproductive isolation
Define sympatric speciation and give an example
A new species arising within a population occupying a single habitat or within the dispersal range of a population
subpopulations occupy the same area at the same time, have opportunities to breed
Within the same population of frogs, mating calls vary in frequency and timing, some females may prefer certain times or frequencies
Define adaptive radiation
Evolution from a common ancestor to divergent forms adapted to distinct ways of life
What are his two stories for genetic drift and catastrophe?
Northern elephants seals recovered from a population low of 20, even though their numbers are high their diversity is very low and the species is vulnerable →
When introducing an endangered species from captive breeding you need enough to avoid founder’s effect → release of 100s of hellbenders
Define parasitism, parasitoidism, and endoparasitoidism
Parasitism: One benefit, other is harmed
Parasitoidism: One benefit, other is killed
Endoparasitoidism: Parasite lives in the internal organs or tissues of its host
Define allelopathy
The effect of metabolic products of plants on the growth and development of other nearby plants
What types of plants do broom sedges inhibit?
Shrubs
What do bracken ferns secrete and what types of plants do they inhibit?
phenolic acids
conifers
What do black walnut trees secrete and what types of plants do they inhibit?
precursor to juglone
broadleaf plants
What do bamboo plants secrete and what types of plants do they inhibit?
phytotoxins
ferns
What are plant secondary compounds? (PSC)
Compounds that are not directly related to plant growth
What are the two possible (theoretical) outcomes of competition?
competitive exclusion and co-existance
Describe competitive exclusion. What principle does it work on? What does it assume?
Gause’s Principle: When two or more species coexist using the same resource, one must displace or exclude the other. Complete competitors cannot coexist. When the niche overlaps too much only two outcomes → one or more species may start to explore other niches
Assumptions: Environmental factors remained constant, no emigration/immigration, competitors genetically unchanged
Describe co-existence in a guild
A group of species utilizing a gradient of resources in a similar way (examples of species with different lengths of roots, chipmunks on a hill, cats with different diameter of teeth)
Define character displacement and give an example
Shift in species’ morphology, behavior, or physiology as a result of natural selection resulting from interspecific competition.
Shift in finch beak size to avoid competition
Define niche and give the three characteristics
The functional role a species plays in an ecosystem; the range of physical and chemical conditions under which a species can persist and the array of essential resources it utilizes.
→ Unique to a species
→ No two species can occupy the same niche in the same ecosystem
→ A multidimensional description
Define fundamental niche vs realized niche
Fundamental Niche: niche if free from interference from other species
Realized Niche: fundamental - subtract competition
Define predation
the consumption of one living organism by another
Describe a general predator-prey cycle
As the predators eat the prey, they lower the abundance of food for themselves, thus decreasing the level of predators, thus allowing more prey to grow, thus increasing level of predators. In a real scenario this would not be a perfect in sync relationship.
What are some reasons why clear predator-prey cycles are not seen?
The prey population is density-dependent (i.e., internal regulation).
Almost every species is attacked by more than one species of predators. Most predator species attack more than one species of prey.
Long-term monitoring data not exist
45 years of data on hellbender populations
Describe the snowshoe hare example of predator-prey population dynamics
In the winter they eat buds of conifers, twigs of aspen, alder, willow
When the population of the snowshoe hare was high, the lynx population was also high; vice versa
Their predator-prey cycle was around ten years (would see a great peak in population of both the hare and the lynx at the same time every ten years)
What are the three major hypothesis about the population dynamics between the lynx and snowshoe hare
Simple Predation
Conventional predator-prey cycle
Simple food limitation
Survey food abundance over ~12 years, close relationship between drop in woody browse (winter food) and drop in snowshoe hares and lynxes
Fluctuating secondary compound contents
Plants (especially in winter) will create secondary compounds that are toxic to hares and will mess with their digestive function -> reduce total energy -> less energy for reproduction
Explain the limiting factors for the minimum population of prey and the maximum population of predators
When the population gets down too low, it is hard for predators to find and kill prey
When the prey species becomes more abundant, the predators eat more and there is more energy, they can only get so much energy however
The per capita rate of predation increases as the prey become more abundant. As the number of prey captured increases, the time spent handling prey increases, slower further increases in the rate of predation
As the proportion of time spent handling captured prey increases, the time spent searching decreases
Give some examples of (non-plant) chemical defense
Employed by toads, snakes - peptides (only a few amino acids, very toxic to central nervous system), alkaloids (caffeine is one)
Give some examples of camouflage or crypic coloration
Flounder - match the background
Walking sticks -resemble twigs
Year-old deer possess white skin spots in order to blend in with sunlight penetrating the forest
Give some examples of flashing coloration/shape
White-tailed deer flash their tail when in danger to warn other deer
Owl butterflies have fake eyes. Since predators attack the neck and eyes of their prey, the predators will attack the wings and the butterfly will survive
Give some examples of warning coloration
Monarch butterfly (north to central america) cause contractile force of the cardiac muscles
Strawberry poison dart frog have sodium channel disruptor; convulsion/paralysis
Describe the two types of mimicry
Batesian mimicry: non-toxic resembling tox
Mullerian mimicry: distasteful, mimic each other. The predators need to be exposed to only one coloration to recognize the signal, gives them more examples
Give some examples of behavioral defenses
Redirect predators (mother bird distracting the predators by acting injured)
Scatter around (schools of small fish swim together, then scatter when a predator gets close so they don’t have time to choose a good prey
Form a concentrated formation (musk ox)
Describe timing reproduction as a method for defense
Reproduce in a very short period of time or shift timing of reproduction to avoid predators (If predators are active in day, you become active in the night; in hibernation try to avoid being present the same year their predators are active)
What are the three types of PSCs that have nitrogen in their heterocyclic ring?
Alkaloids, cyanogenic glycosides, nonprotein amino acids
Describe the PSCs alkaloids, cyanogeneic glycosides, and give an example of nonprotein amino acids
Alkaloids (work on calcium channels and membrane proteins)
Cyanogenic glycosides (converted to HCN in the body)
Nonprotein amino acids, L-DOPA mimics tyrosine in epinephrine and norepinephrine
What are the four types of PSCs that do not have nitrogen in their heterocyclic ring?
Phenolics, polyphenolics, flavonoids, terpenes
Give an example of a polyphenolic and its mechanism, and give the mechanism for flavonoids and terpenes
Tannins (creates bitter taste in unripe fruit)
Crosslink and cause dysfunction in digestive enzymes → diarrhea and lower efficiency
Plant pigments Estrogenic activity (mimic estrogen, cause stillbirths or miscarriage)
Volatile, maintained in vacuoles, consumption causes release and bad odor
Define community
A group of interacting plants and animals living in a given area in the same period of time
Describe the factors that determine community diversity
Richness= the amount of species in an environment
Evenness= measure of the relative abundance number of each species (abundance is # of individuals from that species divided by total # of individuals)
Name the two major methods for determining the productivity of a community
biomass, biodiversity
Describe biomass vs standing crop biomass
Biomass: Weight of living materials, dry weight per unit area
Standing Crop Biomass: Total amount of biomass per unit area in a given period of time
Describe the Shannon Index of Biodiversity
Find the proportion of each species, find natural log of proportion, then multiply proportion by natural log, sum for all species and multiply by -1 (bigger number wins). Considers both richness and evenness
Describe the coefficient of community
For comparison of two communities → Multiply 2 by the number of species common to both, then divide by the sum of the number of species in both communities (higher is better). Considers only richness.
Describe percentage similarity
Find all the species common to both. Sum up the lowest percentages for each species. Considers relative abundance. Ex: Community 1 has 13% abundance of species A and 45% abundance of species B and Community 2 has 23% abundance of species A and 39% abundance of species B. Percentage similarity is equal to 13+39.
