Tinbergen's Ultimate Questions Flashcards
Define adaptive value
- How does the behaviour help the animal survive and reproduce in the situations it is adapted for?
- How does the behaviour affect the chance that the genes that produce the behaviour will be passed on?
What is adaptive value also known as?
Function
Survival value
What does adaptive value refer to?
Evolutionary fitness
When people think of adaptive value as a function what are they usually refering to?
Proximate goals of behaviour
What is meant by a proximate goal?
What is that animal trying to get out of doing that behaviour in the present/immediate future?
How is proximate function an indirect adaptive value?
Proximate function is an indirect adaptive value if the proximate goal helps the animal survive and later reproduce in an ultimate sense
When does proximate function not contribute to ultimate function?
Sometimes the proximate function does not contribute to ultimate function when it is maladaptive
When the proximate function could reduce future survival/reproduction
Describe adaptive value
If the behaviour hinders overall reproduction success it won’t pass to future generations
This is maladaptive
For adaptive value to work you need the following
If the behaviour increases overall reproductive success the genes producing it will increase in future generations
Over time the gene that triggers the behaviour will increase within the population until it becomes a species characteristic
Which 2 ways can the behaviour increase overall reproductive success?
1) The behaviour makes the individual more attractive to the potential partner
2) The behaviour correlates with a special ability
Give an example of an adaptive behaviour
Kin selection
What is kin selection?
Kin selection is where many individual animals won’t breed but will instead help raise the young of other individuals
In some species helpers will give up food and a chance to reproduce to help their relative instead of themselves
What is Hamilton’s rule?
Relatedness X
reproductive benefit to relative}
}reproductive cost of the helper
} = More than crocodile maths sign
rB}C
Kin selection happens when the relatedness, multiplied by the reproductive benefit outweighs the reproductive cost to the helper
How does Hamilton’s rule show how genes will spread?
Hamilton’s rule shows that genes will spread if:
- The helped relative is highly likely to contain the same gene
- If the amount of help given can cause the helped relative to produce more offspring than both individuals would have been able to produce alone
Give an example of how help from kin selection is not obviously related to reproduction, but it helps relatives survive and thus have a chance to survive
Alarm calling is an example
Give an example of kin selection through alarm calling in nature
This can be seen with Belding’s ground squirrels
An individual Belding’s ground squirrel will produce a whistle like call to warn members in its colony that a predator is nearby
The individual calling will stay above ground calling until everyone is safe underground, meaning the individual squirrel calling is easily identifiable to the predator and is frequently killed
In 2010 Freeman et al did a study on why Belding’s ground squirrels do this
They found that 80% of the squirrels making the alarm calls are older females
They theorised that older females are more likely to make alarm calls because:
- the older females have more relatives to protect in the colony
- the older females have a lower chance to reproduce successfully
Making an alarm call seems like a bad idea, but because she protects her relations the alarm calling behaviour is favoured by natural selection