BIO220 Lecture 5 Flashcards
Parent offspring conflict
Genes favoured by natural selection…
Favoured genes ALWAYS increase in frequency each generation
What type of genes can natural selection not favour?
Self sacrificial genes
Natural selection acts on…
genes
When is there no parent-offspring conflict?
Amount offspring trying to acquire = amount parent provides
B(p)
fitness of current offspring
C(p)
Number of future offspring given up
What are offsprings trying to maximize?
B(p) - 1/2C(p)
What are parents trying to maximize?
1/2B(p) - 1/2C(p)
Optimal provisioning rate
How much offspring / parent wants to get / give
The optimal provisioning rate for parent and offspring is similar in…
The cost to future offspring (1/2 C)
What is the conflict in the optimal provisioning rate between parent and offspring?
Parent want to give less than offspring want to receive
Why do parents want to give less than offspring want to receive?
Benefit of providing a lot for current offspring is the same as for future offspring (in terms of parents)
Benefit of providing for current offspring (you) is more beneficial than providing for future siblings (in terms of you)
Why is there parent-offspring conflict?
Due to differences in relatedness
What usually happens when there is a parent-offspring conflict?
Compromise
Example of a species that is all maternal care
Golden lion tamerins
Example of a species that is all paternal care
Pipefish
What are the benefits and cons of deserting current offspring?
Benefit: increase quantity of offspring produced
Cost: decrease quality of offspring (might die)
When is female care usually provided? (in terms of deserting)
Cost of deserting high, benefit of deserting low for females.
Cost of deserting low, benefit high for males.
When is female care usually provided?
Females limited by resources. Don’t have enough to produce numerous offspring.
When is male care usually provided? (in terms of deserting)
Benefit of deserting low, cost high for males.
Benefit of deserting high, cost low for females.
When is male care usually provided?
More females in population than male.
Females have access to a lot of resources.
What experiment was done to predict if female or male care will be provided?
Done on Kentish Plovers in Turkey
What does low re-mating time signify?
High benefit of deserting (can get another mate pretty fast)
What does high re-mating time signify?
High cost of deserting (can’t reproduce again)
Kentish Plovers…which parent provide care?
Male
What does low brood survival signify?
High cost for deserting
What does high brood survival signify?
Low cost for deserting
Evolutionary medicine
Applying evolutionary principles to health problems
What is the approach to evolutionary medicine?
Asking ultimate questions (why things are affected by evolution)
What is the purpose of evolutionary medicine
Better understanding of the cause of illness:
- Prevention
- Treatment
Will vaccines lead to the evolution of pathogens?
Yes
3 reasons why we are vulnerable to disease:
- Tradeoffs
- Environmental change
- Pathogen evolution
Tradeoffs make us vulnerable to disease because…
Can’t maximize defences against pathogens because it comes at some vital cost to other part of body (and we need this part)
Environmental change make us vulnerable to disease because…
We evolve in some current environment, but if the environment changes faster than we do, our body won’t be optimized
Pathogen evolution make us vulnerable to disease because…
pathogens can evolve faster than we can -> fast replications and mutations
Another word for aging
Senescence
Senescence
Progressive decline in somatic function reflected in reduction in fertility and survivorship
Proximate cause of aging
Degeneration of the soma
General degeneration of the soma include…
- impaired function
- increased disease
Mortality rate increases with…
age
Mortality of what disease increases with age?
CVD
Mortality of what disease doesn’t really increase with age?
Cancer
Which bird age much slower than humans?
Fulmar
How long is adult life for a mayfly?
1 day
How long is adult life for bristlecone pine?
5000 years
In terms of aging, different species…
age at different rates