MBIOL161: Pete's Lectures Flashcards
What are Tinberg’s 4 Questions?
Control - how does it work?
Ontogeny - How did it develop?
Function - What is it for?
Evolution - How did it evolve?
What is behaviour?
Sum of responses of an organism to internal + external stimuli and it can be instinctive or learned
What does natural selection select on?
Phenotype
Name 4 phenotype aspects of Life-History strategy
Age and size @ maturity
Number and size of offspring
Sex-allocation
Life span
Name 4 phenotype aspects of Behavioural Ecology
Mate choice
Foraging
Parental care
Competition for resources
What is meant by extended phenotype?
the idea that phenotype shouldn’t be limited to biological processes but extended to include all effects that a gene has on its environment, inside or outside the body of an individual organism.
What extended phenotype do beavers show?
Dam building
How do male 3-spined sticklebacks show control of behaviour?
When they see a red underside (visual cue) it triggers their aggression
How do American Blue Jays show ontogeny of behaviour?
Naïve blue jays will initially eat monarch butterflies, but since they are packed with alkaloids, the jays will throw them up. After this, they will ignore monarch butterflies and anything similar-looking (a form of behavioural learning).
How do male sedge warblers show function of behaviour?
Sedge warblers are migrants and need to be quick with finding their mates. Males with larger repertoire sizes quickly find mates while those who do not take longer to find mates. A larger repertoire size is indicative of a good quality male because it means they have survived multiple migration cycles to pick up on songs and thus show a good fitness that females would want to pass on to their offspring.
Why does claw waving in male fiddler crabs occur? Give 2 reasons
-Due to approach of male or female crab into territory of male
-Hormonal levels
How has claw waving developed?
When small, both male and female crabs have their claws at the same size and are of equal weight. However, when males mature and become larger, the right claw starts to develop more than the other, eventually becoming about 38%. Meanwhile, female claws remain about 8% of their body weight throughout their whole life.
How does claw waving function? List 3 functions.
To defend burrows against rival males
For species recognition
Mate attraction
How did claw waving evolve?
Genus: Uca - all crabs show marked cheliped (claw) asymmetry and use it for signalling
Family: Ocypodidae (which include ghost crabs, fiddler crabs etc) - has common asymmetry and also signalling function
Order: Decapoda - cheliped asymmetry is again common. However, some groups use the cheliped for signalling and some for foraging.
What are Darwin’s 4 Postulates?
- Variation (at a phenotypic level) within individuals
- Some of these variations need to be inheritable
- Some organisms will survive and reproduce, while some will not (natural selection theory)
- Survivorship and reproduction success events are not random
What is microevolution?
Rapid population level changes in relative frequencies of alleles
List 2 differences between macro and micro evolution
Macro = between species variation and leads to clade evolution
Micro = within-species variation and leads to anagenetic change
What was economist Malthus’ extreme view?
That the population would outgrow limited resources very quickly
Explain how the Galapagos Finches provide evidence for Darwin’s 4 postulates
1st Postulate = on the Isla Daphne Major island, there was variation in beak depths and lengths in the finches e.g. finches with large chunky beaks and finches with thinner and longer beaks.
2nd Postulate = Finch parents that have chunky beaks (BB phenotype) will give rise to offspring with chunky beaks as well and finch parents with thin, slim beaks (PP) will give rise to offspring with thin, slim beaks; finches with BP heterozygosity will produce offspring with an intermediate.
3rd Postulate = When drought hit the island, a greater number of finches with chunky beaks survived and got to reproduce while those who did not died off.
4th Postulate = It was not random that finches with chunky beaks survived and reproduced because they had adapted to the hard seed casings that plants produced due to the drought.
What is fitness?
The measure of reproductive success
What is an adaptation?
A trait that enables an organism to survive and reproduce better than if it lacked the trait.
True or False: Evolution takes aeons to occur
False
True or False: The carbonaria morph of Biston betularia over years is evidence of micro evolution.
True
Which period did trilobites go extinct?
Triassic