Lecture 16

Question 1

on average the time between copulation and fertilization is about – hours

Answer 1

72

Question 2

Once the mature ovum (with yolk) is released into the ——– it can be fertilized

Answer 2

infundibulum

Question 3

If female copulates with more than 1 male, the sperm from which male is most likely to fertilize eggs?

Answer 3

last male

Question 4

egg is in ——- for about 24 hours for most spcies

Answer 4

oviduct

Question 5

describe how long is stays in each part of the reproductive tract

Answer 5

1. short time (20-30 mins) in infundibulum 2. 3 hours in magnum region where albumin is added 3. 1 hour in isthmus region where shell membrances are added. 4. 20 hours in uterus region where outer shell is added.

Question 6

what can affect how pigments get on the shell?

Answer 6

how the papillae move and twist the egg

Question 7

—– is the primary nutrient source

Answer 7

yolk

Question 8

label as much as you can

Answer 8

Question 9

chalazae:

Answer 9

twisted proteinaceous strands which suspend the yolk and allow it to rotate

Question 10

air cell:

Answer 10

this allows gas transfer. Oxygen transfers in other areas iof the cel as well but this is like a reservoir of air

Question 11

albumen:

Answer 11

90% water and 10% protein. is the embryos water supply but also serves as a shock-absorer to help protect the embryo. Buffers embryo from sudden changes in temperature

Question 12

what is the maternal effect through the yolk?

Answer 12

yolk also transfers antibodies and hormones to the emrbyo.

Question 13

why did females give more testosterone to younger siblings?

Answer 13

give them a chance to compete with older

Question 14

Tradeoffs with T-levels?

Answer 14

why not have maximum levels of testosterone in eggs? could compromise immune function of both nestling and adults.

Question 15

wat gender determines sex ratio of gender?

Answer 15

females are the heterogametic sex

Question 16

the egg shell is formed of what?

Answer 16

calcium carbonate crystals

Question 17

are reptile or bird egg shells more complex?

Answer 17

bird

Question 18

why is their a limit for how many pores are in an egg?

Answer 18

important to have pores for gas exchange but there is a limit because if there is too much water is evaporated too fast

Question 19

how do birds acquire Ca for the shell?

Answer 19

1. Increase intake of Ca during laying.
2. Females can transfer up to 12% of bone mass to eggs in part through the medullary bone. Leftover crystals in the medullary are reabsorbed into the bloodstream

Question 20

what are 3 reasons why eggs have colour?

Answer 20

1. coloured/patterned eggs evolved in sites vulnerable to predation
2. coevolution with brood parasites may influence colour
3. Pigmentation of eggs may make the shells less brittle and more resilient to breakage

Question 21

do eggs in safer nests such as in tree hollows need camoflauge colour?

Answer 21

No they are brighter so the females can see them in the dark nest site

Question 22

describe how eggs can signal female quality.

Answer 22

producing the blue pigment (biliberdin) derived from haemoglobin is energetically costly. Brighter eggs are associated with beter quality femeales. The brighter the egg the more yolk and larger they are.

Question 23

did male provision change with egg colour brightness?

Answer 23

yes in some and no in others and maybe in others too

Question 24

what kind of birds have intraspecfic variation in egg colour and why?

Answer 24

colonial birds, dont want to confuse between your eggs and neighbors egg

Question 25

spherical eggs:

Answer 25

maximize shell strength, heat conservation and need for shell materials

Question 26

pointed eggs:

Answer 26

maximize egg size for when the eggs are relatively large compared to body size. (eggs pack in better under brood patch). Roll in a tight arc so they dont fall of cliif ledges

Question 27

relative egg size------- with body size

Answer 27

declines

Question 28

are egg size larger in precocial or altricial birds?

Answer 28

precocial. also have relatively larger yolks and higher levels of lipid and proteins

Question 29

Nidicolous:

Answer 29

stay in the nest for a prolonged period (hawks, songbirds)

Question 30

Nidifugous:

Answer 30

leave the nest shortly after hatching (ducks, grouse)

Question 31

which bird has one of the most underdeveloped nestlings?

Answer 31

flickers! Have only 16% yolk and have to stay in nest for usually 25 days.

Question 32

what do flicker babies have on their beak?

Answer 32

white tips calcium hard covering on the tip of the bills that many nestlings have during hatching to break through egg and called egg teeth. Most fall of within a day of hatching

Question 33

usually later eggs dont survive but not in what genus?

Answer 33

eudyptes

Question 34

what is the usualy egg laying interval?

Answer 34

usually 1 per day

Question 35

what are 6 general patterns of clutch size variation?

Answer 35

1. Inverse relation between parental feeding CS. precocial clutch sizes larger than altricial. 2. controlling for species, often CS increases with latitude (less comp in arctic) 3. within a breeding season, clutch size declines with laying date. 4. Young birds lay fewer eggs than older ones. less experienced. 5. clutch size may be correlated with food supply or habitat 6. Cavity nesters often have larger clutches than open nesters. Literally not putting all your eggs in one basket

Question 36

2 ways a female can get nutrients for eggs:

Answer 36

Capital: she accumulates body reserves before laying, then uses this reserve to for eggs. arctic Income: use the food ingested on a day to day basis. Birds in more tropical or temperate environments

Question 37

what are the 2 hypotheses for laying date CS trend? Not mutually exclusive.

Answer 37

1. Adult quality hypothesis: better females laying early in spring 2. Environmental quality hypothesis: those that arrive early and access the better food.

Question 38

what is the difference between determinate layers and indeterminate layers?

Answer 38

determinate layers, CS is fixed at start of laying and cant be altered by adding or removing eggs. Whereas indeterminate layers respond to egg removal or addition by adjusting the number of eggs they produce.

Question 39

Incubation limitation hypothesis:

Answer 39

maximum clutch is limited by number of eggs that can be incubated. Like penguins who incubate on their feet