Chapter 14 (forms and function)

Question 1

what are the general ways that fish have evolved?

Answer 1

structural, physiological, behavioural adaptations

Question 2

what type of fishes do we know the most about, reproductively?

Answer 2

aquarium fishes (primarily Osteriophysi and members of family Cichlidae)

Question 3

what categories are reproductive guilds separated into?

Answer 3

ecological and ethological

Question 4

oviparous

Answer 4

lay eggs into their external environment

Question 5

what are the two general kinds of eggs?

Answer 5

Pelagic (eggs that float)

Demersal (eggs that sink)

Question 6

what are the three group type of pelagic egg-layers?

Answer 6

1- most all fishes that live over the continental slope
2- nearly all those that range over surface waters of the open ocean
3- all pelagic deep-sea fishes

Question 7

how do pelagic eggs stay buoyant?

Answer 7

low density fluids or an oil droplet

Question 8

what happens when a pelagic egg hatches?

Answer 8

releases a colorless larva that, after its yolk sac is used up, survives off of PHYTOPLANKTON AND ZOOPLANKTON

Question 9

what can be said of the dispersal of pelagic eggs?

Answer 9

survival rate is really low, they have wide geographic distributions

Question 10

where do most of dermersal egg-layers live?

Answer 10

in near-shore waters, and a lot live between tide marks. tidepool forms

Question 11

how do demersal egg-layers combat tidepool environments?

Answer 11

sinkable eggs, or anchored eggs to substrate do well here.

Question 12

geographically, what kind of distribution do demersal eggs have?

Answer 12

restricted geographic distribution

Question 13

what are some reasons why demersal-egg layers lay fewer eggs?

Answer 13

fishes are smaller, larger eggs, larvae take longer to develop and emerge more advanced in development. also they dont get swept away

Question 14

what is the danger to demersal,attached eggs? what evolves from this?

Answer 14

predation. they hide their eggs, and develop parental care.

Question 15

what are five differences between pelagic and demersal eggs?

Answer 15

demersal:
large: >1mm
gravity: greater
egg envelope: thicker
Transparancy: opaque
amount of yolk: large
development: 2 months (a week or less for other)

Question 16

WHY ARE DEMERSAL EGGS THE RULE FOR FW FISHES?

Answer 16

1: PHYSIOLOGICALLY MORE DIFFICULT to produce an egg w specific gravity less than fw
2: fw DOESNT PROVIDE THE RICH FOOD RESOURCE in its upper layers as does for marine
3: fast rivers/streams REMOVE A LARGE PROPORTION OF EGGS AND LARVAE (limit recruitment)

Question 17

how many FW species in N. America have pelagic eggs?

Answer 17

ONLY ONE!! (FRESHWATER DRUM (SCIAENIDAE)

Question 18

what is the correlation between stickiness of eggs and parental care?

Answer 18

nearly all fish deposit eggs that stick or sink. great numbers of non-adhesive eggs get no parental care.

Question 19

what are some manner of protecting fw eggs?

Answer 19

build NESTS involving COMPLEX BEHAVIORAL DISPLAYS, hide and protect eggs in other organisms (EUROPEAN BITTERLING IN FW MUSSELS)

Question 20

what is the symbiotic relationship between the bitterling and fw mussels?

Answer 20

mutual exchange of gametes

Question 21

similarity between ovoviviparous and viviparous

Answer 21

live bearing forms

Question 22

how do ovoviviparous and viviparous differ?

Answer 22

source of nutrition for developing young.

Question 23

Ovoviviparous

Answer 23

eggs are retained and fertilized within the body, young get no nutrients from mother. rely on YOLK.

Question 24

Viviparous

Answer 24

young are nourished by some kind of PLACENTAL CONNECTION with the mother

Question 25

what do scientists questioning the dichotomy between ovoviviparity and viviparity suggest is a more conservative approach?

Answer 25

call all fish that give birth to live young viviparous (live bearers)

Question 26

name members who are ovovivi + viviparous

Answer 26

chondrichthyese, live beareres, guppies, fw halfbeak, scorpionfishes (scorpaenidae) surfperches (embiotocidae), brotulas, eelpouts (zoarcidae) clinids, coelacanths

Question 27

where can you usually find a INTROMITTANT ORGAN used to pass sperm to a female?

Answer 27

usually modified anal or pelvic fins

Question 28

explain the ovoviviparity in guppies

Answer 28

eggs are fertilized within EGG FOLLICLES or the OVARY. follicles rupture, embryo completes development in the cavity of the ovary. sustained off of yolk nutrients.

Question 29

Superfetation

Answer 29

maintenance of batches of embryos at various states of development.

Question 30

explain how developing youngs get nutrition in viviparous forms

Answer 30

placental connection, sometimes walls of ovarian follicle use network of capillaries that extend out as VILLI and make intimate connection with surface of embryos.

Question 31

some other forms of viviparity

Answer 31

pseudoplacenta, branchial placenta, TROPHONEMA.

Question 32

trophonema

Answer 32

food absorbing processes that grow out of the hindgut of the embryo

Question 33

name 4 forms of parental care

Answer 33

1- Male parental care 2- female parental care (ovo w/ post-spwn care), (ovovivi w/o post-spwn care), (vivi w/o post-spwn care) 3-biparental care 4-juvy helpers

Question 34

describe some forms of male parental care

Answer 34

oral incubators/mouth brooders, bony hook head

Question 35

where would you generally find the most hermaphroditic species?

Answer 35

in the deep.

Question 36

what are two types of hermaphroditism, and what defines them?

Answer 36

simultaneous hermaphrodites: produce both egg and sperm. | Sequetial hermaphrotism: can do a sex change, but usually once its done, its done.

Question 37

WHY SWITCH SEX? WHICH SEX DO YOU START WITH? WHEN DO YOU SWITCH?

Answer 37

talk these thru with Jer :)

Question 38

PROTANDRY. example?

Answer 38

first half of life cycle is spent in the male state. Anenomefishes.

Question 39

PROTOGYNY

Answer 39

first a female, then a male. (sex switch)