Exam 2 Lecs - 2

Question 1

• Both female frogs and predators attracted to males with …
• Some of the morphological differences between males and females can be explained by … alone –> female and male hummingbirds have different beaks bc better adapted to …

Answer 1

complex calls;
natural selection;
eat from different flowers

Question 2

• female weevils use their apparatus to … and … in deeper burrows where they are better protected
• higher … for female orangutans - this is typical of mammals

Answer 2

bore holes;
deposit eggs;
parental investment

Question 3

• even when parental care isn’t provided, … generally demand more energy for production as compared to …
• males’ fitness more greatly influenced by …

Answer 3

eggs;
semen production;
variation in mating success

Question 4

For newts, most males don’t find mates. For females, there are no females with …

• offspring variation is not as large for … newts as for the opposite sex.
• with increased number of mates, there are increased number of offspring - this pattern is much more pronounced/stronger in … as compared to the opposite sex

Answer 4

0 mates;
female;
males

Question 5

with increased number of mates, there are increased number of offspring - this pattern is much more pronounced/stronger in males as compared to females.
- this changes if sex that … changes - e.g. seahorse and pipefish

Answer 5

invests more energy

Question 6

with increased number of mates, there are increased number of offspring - this pattern is much more pronounced/stronger in males as compared to females.

this changes if sex that invests more energy changes - e.g. seahorse and pipefish:

• males invest more energy - help … the egg and develop baby in …
• in this case, the relationship is inverted - number of mates then becomes more important for … than for opposite sex, as they now have to …

Answer 6

oxygenate;
pouch;
females;
convince males to mate

Question 7

if chance of mating more strongly determines number of offspring, … will be stronger for that sex
- if ability to convince other sex to mate is directly related to number of offspring, will evolve more elaborate ways of … –> for the other sex, where sexual selection is not that strong, they will be …

Answer 7

sexual selection;
convincing the other sex to reproduce;
the choosy sex

Question 8

competition among males generally occurs through …

- evolving … body sizes, …, …, etc. (e.g. marine iguana)

Answer 8

combat;
larger;
weaponry;
armor

Question 9

competition among males generally occurs through combat - e.g. marine iguana:

• but, natural selection occurring as well - thus, … selection on size for iguanas
• very large iguanas have … and tend to …

Answer 9

stabilizing selection;
energy deficit;
lose weight

Question 10

competition among males generally occurs through combat - e.g. marine iguana:
- stabilizing selection on size for iguanas - very large iguanas have energy deficit and tend to lose weight –> need to … much more than they can, limit on … depending on … (i.e. algae) available

Answer 10

feed;
size;
amount of resources

Question 11

competition among males generally occurs through combat - e.g. marine iguana:
limit on size in iguanas:
- in both santa fe and genovesa, the sizes are larger than the maximum size at which they can … - the reason is due to …
- females may be attracted based on … that males control.

Answer 11

maintain their weight;
sexual selection;
territory

Question 12

competition among males generally occurs through combat - e.g. marine iguana:

• females may be attracted based on territory that males control. Thus, males … for these territories and generally … males win
• males that copulated in both islands were … than those that merely tried to mate

Answer 12

fight;
larger;
significantly larger

Question 13

competition among males generally occurs through combat - e.g. marine iguana:

• males that copulated in both islands were significantly larger than those that merely tried to mate –> larger males have more success
• development of … in this case. Small males, despite not having territories, still manage to get about …% of the matings

Answer 13

alternative mating strategies;

5

Question 14

lions live in groups where all the females are related to one another
- stronger males challenge those that are already with those females. they … and push out those males and become new mates for those females. Those males then … already there such that females can be receptive to … earlier, bc , while females are …, they cannot breed

Answer 14

fight;
kill all the cubs;
mating;
lactating

Question 15

lions live in groups where all the females are related to one another:
- … is significant cause of lion mortality

in the case where males can’t monopolize females/resources, males then … –> …

Answer 15

infanticide;
advertise for mates;
elaborate courtship rituals

Question 16

Trimmed tails of males of red-collared widowbird:

• tails used as … display for females
• two sizes: short and then control groups, then measured body condition index (e.g. …) –> wanted to know if males with longer tails need more … to survive

Answer 16

sexual;
weight;
energy

Question 17

Trimmed tails of males of red-collared widowbird:
wanted to know if males with longer tails need more energy to survive
- keep …. after territory establishment for those with short tails (I think it was actually for the ones with longer tails)? –> they lose weight at a …
- those with longer tails have … than short tailed males
- interaction between … and …

Answer 17

losing weight; 
faster rate; 
more mates; 
natural selection; 
sexual selection

Question 18

choosy females may benefit directly through the …
- benefit for males who capture larger prey - more time for females to … and therefore more time for … during copulation

Answer 18

acquisition of resources;
eat;
sperm donation

Question 19

By choosing males, females can also get … for offspring - higher …

Answer 19

better genes;

fitness

Question 20

By choosing males, females can also get better genes for offspring - higher fitness:
for frogs:
- males with long calls and with short calls
- identical females copulating with different types of males
- females like … males
- ran an experiment and compared tadpoles from different crossings and ran tadpoles on high food diet and low food diet and compared development of tadpoles –> found that offspring of long calling males had …, higher …, better …

Answer 20

long calling;
faster larval growth;
mass;
larval survival

Question 21

By choosing males, females can also get better genes for offspring - higher fitness:
for frogs
- results of this experiment supports hypothesis that choosy females get … for their offspring
- this results bc females that choose the best genes will have more offspring with higher fitness - that … will then pass onto next generation. next females that choose same, better males as mother will also produce … offspring

Answer 21

better genes;
choosiness;
higher fitness

Question 22

By choosing males, females can also get better genes for offspring - higher fitness:
for frogs:
- selection of females that make …
- males also advertise their good genes with …
- … acting here

Answer 22

better offspring;
longer calls;
natural selection

Question 23

can have sexual selection on females as well:

• …: multiple mating by females
• prairie dogs –> number of … influences number of offspring. advantageous for females to …,

Answer 23

polyandry;
sexual partners;
mate with more males

Question 24

can have sexual selection on females as well
- prairie dogs: number of sexual partners influences number of offspring –> higher probability of … and … for those who had more mates - pressure for females to …

Answer 24

getting pregnant;
giving birth;
have more mates