Lecture 1 Flashcards
what do Filter feeders eat
suspended particles from water
define Quantitative trait
Traits where the phenotype can be measured
on a continuous scale
define qualitative trait
the phenotype is measured on a
categorical scale. eg blood
is height qualitative or quantitative?
Quantitative
define Morphological traits
Traits where the phenotype has to
do with the shape, structure,
colour, pattern, or size of an
individual/species
define Behavioural traits
Traits where the phenotype has to
do with the behaviour of an
individual/species
define Life history traits
Traits related to timing of
development and reproduction;
longevity; number/size of
offspring
Is height a morphological, behavioural, or a life history trait
morphological
is bird migration a morphological, behavioural, or a life history trait
behavioral
is number of elephant offspring per year morphological, behavioural, or a life history trait
life history
what is a Heritable trait
Traits with phenotypes that are
genetically inherited from biological
parents (DNA)
what is Heritability a measure of
how important genetics are to determining
a trait
Phenotypes for traits that are highly heritable will be more likely to
look like what
the phenotype of biological parents – regardless of
environment
~79% of variation we see in human height is due to what
genetic differences
Peter Dinklage (famous for his role as Tyrion Lannister
in Game of Thrones) has a genetic condition called
achondroplasia. Achondroplasia accounts for most cases of dwarfism, where individuals experience
impaired bone and limb growth. Which of the following is the most accurate way to classify achondroplasia?
A. Achondroplasia is a quantitative trait, because it affects height.
B. Achondroplasia is not heritable.
C. Achondroplasia is a qualitative trait.
D. Achondroplasia is both quantitative and qualitative
C. Achondroplasia is a qualitative trait.
define Phenotypic plasticity
When the exact same genotype produces
different phenotypes under different environments
what is this an example of?
Same plant with same genetics is grown in shade vs light and ends up different bc of environment
Phenotypic plasticity
define sexual dimorphism
vary between biological sexes in a species
what is a dioecious species
species that have separate males and females
Researchers at the Syndenham River were interested in quantifying
mussel biodiversity – which required identifying different mussel species.
What types of traits are most useful for identifying different species of
mussels?
A. Traits that display phenotypic plasticity
B. Traits that are sexually dimorphic
C. Traits that are heritable
D. Traits that are shared by different species
E. All traits are equally useful for distinguishing between mussel species
C. Traits that are heritable
what is taxonomic hierarchy based on
ancestry
Biological units
of organization range from
Biosphere to Molecular
what does Biodiversity usually refers to
the total number of different species
Biological traits are the __________ ___________ of an individual that
manifest in different ways
observable characteristics
Evolution is the process that results in what
changes in the proportion of heritable traits
within populations from one generation to the next
what are the four forces/mechanisms that drive evolutionary changes
Natural Selection
Mutation
Genetic drift
Gene flow
define adaptations
Traits that provide a “fit” between an
organism and its environment
natural selection leads to
adaptation
Finches with deeper beaks are better able to what
eat large/hard
seeds than finches with shallow beaks
Rosemary and Peter Grant study what
a population of finches
on Daphne Island since
1973
Offspring beak depths are similar to what
that of their parents
If beak depth is heritable, then the next
generation of finches will what
resemble the
previous generation of finches that
survived and reproduced
what are Darwin’s Postulates
- Phenotypic variation exists within a population
- Differential reproduction/survival occurs based on that
phenotypic variation - That variation is genetically heritable
what does it mean when these postulates are true?
natural selection is occurring
Which of the following is the best description for why average
beak depth increased in the finch population?
A. Each finch in the population had offspring that had deeper beaks than usual.
B. Finches invested more energy toward growing deeper beaks, which
helped them survive, and then passed these deeper beaks onto their
offspring.
C. Finches with shallower beaks were less likely to survive compared to
finches with deeper beaks.
D. The increase in beak depth occurred by random chance – it would have been equally likely for beaks to become shallower.
C. Finches with shallower beaks were less likely to survive compared to
finches with deeper beaks.
Mutations occur when a change takes place within an individual’s genes.
While most mutations do not impact phenotype (they are silent),
mutations occasionally arise that do alter phenotype. Which of the
following is true about mutation rates in medium ground finches and
the drought on Daphne island?
A. Finches started experiencing more new mutations as a result of the
drought on Daphne island.
B. New mutations for deeper beaks arose more often as a response to
the drought and ensuing change in seed size.
C. New mutations for shallower beaks arose less often as a response
to the drought
D. Neither mutation rates or the probability that a mutations influence
beak depth changed as a result of the drought.
E. A, B, and C
D. Neither mutation rates or the probability that a mutations influence
beak depth changed as a result of the drought
Fitness explains what
evolutionary success of certain organisms
Directional selection
distribution of a trait moves in a single
direction eg finches during drought
Stabilizing selection
Genetic variants that lead to ‘extremes’
(e.g., deep beaks OR shallow beaks)
become less common in the population
over time
Disruptive selection
Genetic variants that lead to average beak
depth become less common in the
population over time – selection favors genetic variants that lead to the ‘extremes’
