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
What does kin selection show about evolution?
Kin selection shows that evolution doesn’t act on an individual level but instead on a genetic level since the genes that help the species are more favoured than genes that help the individual
Give 3 methods to study adaptive value?
1) Observing reproductive success of different phenotypes in a varied natural population
2) Artificially selecting extreme traits and observing reproductive success under specific circumstances
3) Altering the environment and observing reproductive success in animals of different phenotypes
What does phylogeny focus on?
What did the behaviour evolve from?
Why do some species behave this way when others don’t?
Describe phylogeny in the proximate sense
Some interpret phylogeny in a proximate sense, as being about inheritance of a behaviour
This is when they’re talking about behaviour seen in individual animals and not their species
The proximate sense of phylogeny is not an ultimate question and fits more into ontogeny
What does answering phylogenetic questions in the ultimate sense usually mean?
Usually answering phylogenetic questions in the ultimate sense requires comparing related species
The reason why this ultimate question is called phylogenetic explanations is because behaviour is explained by looking at the species phylogeny
What can phylogenetic explanations help explain?
Phylogenetic explanations can help to explain why one species shares behaviour with a distantly related species but not a closely related species
Behaviour evolves more rapidly than many other traits so what does this mean for closely related species?
Behaviour evolves more rapidly than many other traits so it can be quite different even between close relatives
Give an example of how behaviour evolving more rapidly than many other traits can lead to different behaviours between close relatives
This can be seen with cats:
Tigers and jaguars love water and regularly swim, while most other cats avoid water
Caracals and servals jump really high and so can catch airborne prey while most other cats can’t do that
Margays and Geoffroy’s cats are arboreal while most other cats are terrestrial
Lions and feral domestic cats are the only group living felids
Phylogenetic questions about a particular behavioural difference between species can be answered by doing research in whether species do any of the following examples
Live in exposed vs complex habitats
Is omnivorous vs herbivorous
Is social vs solitary
Is a predator vs prey
You can look at other aspects of both species to understand behavioural differences the above were just examples
When answering phylogenetic questions you need to take what into account when doing your analysis of the behaviour?
Phylogeny and species relatedness
When doing a comparative method to look at phylogenetic questions special statistical analytical methods are needed to assess what?
Special statistical analytical methods are needed to assess trends across species while controlling for species relatedness
These analytical methods are necessary because they take into account that species can behave similarly to each other due to a causal link
When using a comparative method the special statistical analytical methods will usually tell you that a behaviour is seen in different species because of what 2 things?
They have a similar lifestyle
They are closely related
This reason is pretty obvious and so wants to be removed from the data analysis since we’re trying to find less obvious reasons for the similarities in behaviour
This is why we use special statistical analytical methods in phylogenetic studies
Statistically speaking species are what from each other?
Statistically speaking species are non-independent from each other
What does statistically non-independent mean?
Some data points are more similar to eachother than other data points further apart due to confounding factors
This means that each species is more similar to its close relatives than its distant relatives
If statistical non-independence is not taken into account when doing comparative methods with special statistical analytical methods then what 2 things will happen?
The sample size will be artificially inflated
Interfering ‘noise’ (in a statistical sense) from phylogenetic similarities will confuse matters
Seemingly odd behaviours evolved from what?
Seemingly odd behaviours actually evolved from functional behaviours originally
What are phylogenetic levels of explanation about?
Phylogenetic levels of explanation are about the evolutionary history of behaviour across different species
Due to this we aren’t necessarily looking at the individual animal as long as we’re using it in the ultimate sense
Give 2 examples of methods to answer phylogenetic questions
1) Comparison of ancestral through to more recent species behaviour to investigate what the recent behaviour evolved from
2) Comparison of behavioural differences between species in terms of aspects of their ecology, anatomy, and other aspects
In each case phylogeny (species relatedness) should be taken into account in the analysis
