Exam 2 Lecs - 1 Flashcards
We should accept a pluralism of evolutionary process:
- full theory of evolution accommodates …
- when we are studying adaptation, it’s sensible to concentrate on … since this is the only mechanism that explains adaptation
drift;
natural selection
can selection explain all known adaptation?
- Darwin proposed that changes occur in very small steps - Darwin’s … requirement is a fundamental property of evolutionary theory
- If mutations arose …, in different organisms at different times, the whole process becomes more probable
gradualist;
separately
Evolution of the eye:
- start with mass of cells sensitive to … - knowing when it’s … (impacts when you look for food, avoid predators, avoiding sunlight bc uv light causes mutation, etc)
- next step is … of that mass of cells to enable knowledge of … of the light
light;
day and night;
folding;
direction
Evolution of the eye:
- next step is formation of a … that’s even more sensitive to direction
- then closing of that cavity bc it can be prone to …
cavity;
infection
Evolution of the eye:
- then closing of cavity bc cavity can be prone to infection. Cavity becomes filled with … which can also help to clean the noise of the night and make vision better
- then can form the … on the top - mass of … to make image clearer
- then formation of eye
water;
lens;
transparent cells
Adaptive landscape idea developed by Richard Dawkins:
the main metaphorical treatment is of a … upon which evolution can ascend only … and cannot climb …
geographical landscape;
gradually;
cliffs
an organ has to be … in all stages of its evolution if it is to be produced by natural selection
function of an adaptation can change with little change in its …
advantageous;
form
function of an adaptation can change with little change in its form: e.g. evolution of ... and the ...
feathers;
tetrapod leg
function of an adaptation can change with little change in its form:
e. g. evolution of feathers and the tetrapod leg:
- these are called …: shift in … of a trait during evolution
- feathers originally evolved for some function other than flight. Initially, feathers were likely more of a …
exaptations;
function;
filament
function of an adaptation can change with little change in its form:
feathers originally evolved for some function other than flight:
- initially, feathers were likely more of a filament
- primarily advantageous for … or …
- first feathers were not …, which is essential for flight
thermal regulation;
courting display;
assymetric
function of an adaptation can change with little change in its form:
- tetrapods evolved from fish Sarcopterygii
- Tetrapods initially developed rudimentary legs as … that helped them … –> lived in … waters. legs could also be used to hold them in these waters. They would go out to … to …
- legs initially used for … not …
fins; swim;
shallow;
land; eat;
swimming; walking
new adaptation can evolve by combining unrelated parts:
- e.g. evolution of … –> one … engulfing another - allowed for creation of … like … (enables …)
eukaryotic cells; bacterial cell; organelles; mitochondria; aerobic respiration
Tradeoffs and constraints:
- Begonia male and female flowers look very similar. Adaptive bc bee … females by visiting both flowers, but only gets a … from the male flowers
- Rate at which female flowers are visited should depend on …
pollinates;
“reward”;
how closely they mimic male flowers
Tradeoffs and constraints:
- larger flowers attract more bees:
- should have … towards larger flowers
- female flowers are not larger though bc then the … flowers you can actually have per inflorescence - it’s a trade off between … and …
directional selection;
fewer;
size; number of flowers
Tradeoffs and constraints:
Fuschia flowers:
- when they have nectar it’s when they’re in the … range of color. So why does the flower change colors over the days? Bc ovary of flower is deep and it takes a long time for … to form –> constraint here: flower needs to stay until formation of … and then they can …
green;
pollen channel;
pollen tube;
drop the flower
