Exam 2 Flashcards
What is fitness?
non-random differences in reproductive capacity
What is an example of adaption as a feature?
A babies head is large but flexible. However this predates live births and all vertebrates have flexible heads even without live birth.
What is preadaption?
vertebrates head example of heads being flexible before live birth.
What is exapptation?
When a species can no longer do what was originally could but has now changed. An example of this is swimming birds that can no longer fly
What things can change features that are not adaptations?
Physical/chemical rules
Drift
Correlation with adaptive trait
What are the levels of natural selection
Alleles -> usually by its effect on individuals
Individuals -> one or both sexes
Population -> groups
Species
What are the most common types of natural selection?
Most common -> Alleles, Individuals
Not common -> Population, Species
True or False -
Processes of NS at different levels may oppose each other
True
What are ways you can tell if something is an adaptation or not and give examples or definitions
Design Principles - follows certain things that benefit the species hence the adaptation from NS. Fish are torpedo shaped which is an adaptation for speed
Comparative Method- Compare multiple species. Monogamous gorillas have smaller balls then polyamerous chimps
Experiments- Conducting an experiment to test a hypothesis. Soard tailed fish, males with had it removed and placed on a different male without one. Then they watched mating patterns.
Natural selection among genes
T locus polymorphism in house mice are starel if they have the homozygouse recessive allele. However the heterozygoes individuals can still reproduce and they have an uneven spread of the recessive and dominant alleles
Natural Selection among Individuals
Spots on guppys are attractive however they attract preditation as well. This means that they are more likely to reproduce but also to be eaten.
Among Groups
Altruistic traits will increase the fitness of others in the groups around the one with the trait. Will always decrease in frequency because of individual selection. The benefit to the group usually outweighed by cost to individual because individuals reproduce faster then groups. Examples are alarm calling, food sharing and grooming
What is kinship?
Offspring resemble their parents
What is altruisim and what can it do?
It is when there is a trait in an individual that benefits the group. These are favored within the groups because they see the benefit and treat the individual nicely
What are three thing they you should not expect of NS?
Necessity - Polar bears having a white coat to blend in to survive
Perfect - The nerve that goes around your artery
Progress - NS is local, no mechanism to explain species anticipating future
(change is varied and unpredictable)
Morality - everything to be fair. The stronger individual is likely to survive over the weaker one in the wild.
True or false -
Without mutation the only variation would be caused by environmental variation
True
How does variation arise?
From mutation and recombination
True or false -
Dominance of an allele does refer to the frequency of the allele
False -
Dominance of an allele does refer to the frequency of the allele