Exam 1 Flashcards
What is an allele
A different form of a gene- mutation
How does evolution occur?
Natural selection
Non random
Gene flow
Movement of genes or alleles in an out of a population
Random
Genetic drift
Chance event occurs to randomly change the frequency of alleles in a population
Hurricane
Cold snap kills many animals
Wildfires in Australia
Random/Luck of the draw
Mutation
Random
Epigenetic mechanisms
What is the Healthy Mate Theory?
Mating with healthy males will less likely pass on parasites and pathogens
Males without parasites or pathogens, will have better feathers, longer horns, etc.
What is the Hamilton- Zuk Hypothesis?
Healthy males have larger ornamentation ( preferred)
What is the Handicap Principle?
Originally proposed in 1975 by Amotz Zahavi
Females prefer males with handicaps that reduce their survival because handicaps are indicators of heritable viability
Experimental study on long-tailed widowbirds
Long tails increases the risk of predation
However, the longer the tails, the more likely males mates with females
The handicap principle may be a form of_______
Runaway selection
Name three Origins of Female Choice:
Sensory exploitation hypothesis
Sexy son hypothesis
Runaway Selection
Define Runaway selection
Sexual selection favours exaggeration of male traits desired by females.
Like a peacock
What is the sexy son hypothesis?
Female mates with male who she perceives will help her produce sexy sons- increase fitness
Attractiveness, physical appearance of male is important
What is the Sensory exploitation hypothesis?
Females have intrinsic preference for appearance/ behaviors based on sensory systems
Non-sexual trait that females choose
Males exploited this system
Example:
Swordtails
Females prefer males with longest tails
What are the two types of sexual selection?
Intraselection
Interselection
True or False: Intraselection is where femals choose their mate
False
What is interselection?
Female choice
What is intraselection?
Male choice
Intraselection leads to…
Polygymy
Interselection leads to
Monogomy
What is the good genes theory
The more physical a male is-> his genes are good
_________ is a form of Natural selection?
Sexual selection
How is sexual selection a form of natural selection?
Nature selects something in the male
Bright colors
Dance
Behavior
Display
Sexual dimorphism
Difference in ornamentation
Size
Color
What is artificial selection?
Selective breeding
Sexual selection leads to….
sexual diamorphism
Which 8 things are occuring if evolution is not taking place?
Mutation is not occuring
Natural selection is not occurring
The population is infinitely large
Smaller populations favor mutation and natural selection than large populations
All members of the population breed
All mating is totally random
Everyone produces the same number of offspring
There is no migration in or out of the population
No gene flow
Environment is not changing
G.H. Hardy was a …..
English Mathematician
Wihelm Winberg was a….
German physician
What does the Hardy-Weinberg equillibrium state
Principle states that both allele and genotype frequencies in a population remains constant, that is there are in equilibrium- from generation to generation unless specific disturbing influences are introduced
If allele and genotype frequencies remain constant, evolution is not occuring
Who developed Punctuated Equilibrium?
Niles Eldredge and Stephen Jay Gould
Who developed Catastrophism?
Cuvier
Define Catastrophism
Catastrophe would occur and wipe something out
Darwin’s evolution
Gradualism