Lecture 15

Question 1

whats the difference between cliff and barn swallows calls and why is there a difference?

Answer 1

cliff swallows are more complicated and specific because they are colonial nesting birds and therefore need to be better at distinguishing between calls than Barn swallows who are soliditary.

Question 2

what bird accept adoption and why is it beneficial?

Answer 2

The Golden Eye! This may protect their own young from predation via the dilution effect. Also little cost to themselves as ducklings are self feeding

Question 3

The desertion thrseshold model:

Answer 3

predicts the brood size at which parents should desert their brood.

Question 4

what are some benefits helps get in helping another pair raise their young?

Answer 4

Gain direct experience and indirect kin-selection benefits

Question 5

what bird is one of the best studied in terms of cooperative breeding?

Answer 5

scrub Jay! May have up to 6 helpers. Helpers stay for 1-7 years before trying for a territory of their own

Question 6

why would helpers help others instead of raising their own?

Answer 6

unpredictable food cinditions may have a young bird stay with mom and dad for another year while and helps raise siblings. Or habitat saturation and they have difficulty finding a good territory

Question 7

helpers are often ——— to the pair

Answer 7

relatives

Question 8

Describe the bee-eaters mating system?

Answer 8

are monogamous but breed in large colonies and the colonies are made up fo clands or extended family. Each clan contains 2-3 mated breeding pairs and they feed, roost and breed cooperativly

Question 9

bee eaters can recodngize ——–

Answer 9

their parents!!! As well the can recognize siblings their parents reared.

Question 10

Brood parasitism: define and label 2 types

Answer 10

Laying eggs in another individuals nest. Conspecific and interspecific

Question 11

Interspecific:

Answer 11

using a different species as a host

Question 12

Conspecific:

Answer 12

using the same species as foster parents. Is more subtle and harder to detect in the field

Question 13

Over — species never build nests of their own

Answer 13

100

Question 14

Falcultative brood parasitism:

Answer 14

optional, depending on circumstances. Build own nest, lay extra effs in others nest. Dependent on opportunity. Intra- or interspecific

Question 15

Obligate brood parasitism:

Answer 15

always, brood parasitism ois only means of reproducoing. Dont buold own nest. Interspefic only. About 1% of bird species

Question 16

what are examples of birds that do falcultative brood parasitism?

Answer 16

red headed and wood duck, yellow-billed and bacl billed cuckoos and colonial species like swifts

Question 17

have are 4 hypotheses for conspecific brood parasitism:

Answer 17

1. Best of a bad job: females become parasitic when environment limits breed opportunities or have poor body condition and cant invest incare. No nest site available.
2. Nest Loss: Lay parasitically if their own nest is destroyed during laying
3. Lifeling specialist: depends on others to rear young
4. Fecundity enhancement: nesting females also lay some eggs parasitically to increase fitness

Question 19

what did the find with Northern flickers?

Answer 19

The practised fecundity enhancement with brood parasitism. 17% of broods had at least 1 parasitic egg and older femeales more likely to parasitize

Question 20

conspecific parasitism is more common in ——– species and —— nesters

Answer 20

precocial. Low for altricial. Colonial nesters

Question 21

How do coots react when they have a foreign egg in their nest?

Answer 21

femeales may recognize some parasitic eggs by their timing og laying or appearance and bury them or evict them. Femeales actually keep count of how many eggs they lay and try for an optimal clutch size. If they are tricked and accept a foreign eff, they lay 1 fewer eggs themselves.

Question 22

specialist brood parasitism:

Generalists:

Answer 22

parasitize specific species

parasitize wide ranfe of species

Question 23

what do eurasian cuckoo chicks do?

Answer 23

maneuver under host eggs and chicks and dump them over the edge of the nest. Their backs have a neatly designed depresson that just fits the competitor egg

Question 24

what is an example of a evolutionary aspect that aids in brood parasitism young killing hosts?

Answer 24

african honeyguide young kill host young with sharp hooks on their bill: hooks that later fall off

Question 25

what are 7 adaptations of obligate brood parasites?

Answer 25

1. destroy/remove host eggs
2. Have hard shelled eggs
3. Short incubation period
4. incubation within females body, can hold in their body better than non parasitic birds.
5. Faster growth rate than host
6. Agression against host chicks
7. Larger size than host chicks

Question 26

explain te gape size constraint hypothesis:

Answer 26

explains why females may feed smaller nestlings more than males. Males may bring larger prey than femeales and hence food transer to a small nestling often fails and they prey item is delivered to a larger nestling. Females bring smaller because of foraging contraintsa and can feed all of thm

Question 27

what are 8 counter tactics by host?

Answer 27

1. Shift breeding season
2. attack parasite
3. warning calls
4. Nest concealment
5. Egg discrimination
6. Young discrimination
7. Removal of parasite egg or young
8. Abandon nest and start over

Question 28

what is the powerful weapon brood parasite have developed in reaction to host species ejecting their egg?

Answer 28

Mimicry- of host eggs, host nestling and host vocalizations

Question 29

——- ——– are unrivaled at laying eggs that resemble their host

Answer 29

common cuckoos

Question 30

mimocry of eggs is carried on what kind of DNA?

Answer 30

naternally inherited mitochondrial DNA

Question 31

—— —– resemble own host nestlings more closely than those of other cuckoos

Answer 31

bronze-cuckoos

Question 32

brown headed cowbirds are ——– brood parasites

Answer 32

obligate. Parasitize 200 species. Matching isnt possible with a wide range of egg and nestlibg morphologies and just lay many eggs in numerous nests.

Question 33

what is the issue with the cowbirds?

Answer 33

there are 3 endangered species for which cowbird parasitism has been identified as a major factor in population decline. Black-capped vireo, least bells vireo and kirtlands warbler

Question 34

why havent more host species of obligate generalists evolved against parasitims?

Answer 34

there is a high cost that you may throw out your own! If you make a mistake you are damaging your own!

Question 35

Parasitism ussualy does not endanger overall populations. why?

Answer 35

Its frequency dependent. Once parasitism comes to a high, there are fewer hoss to support parasitized nestlings. It is self limited by number of potential hosts in the environment. This is really only true for obligate, general is more difficult

Question 36

with some species, the arms race is on going. Describe the battle between bronze cuckoo and Fairy wren

Answer 36

Fairy wrens respond to cuckoo eggs laid before they have started laying by abandoning nest or building over egg. They also abandon if cuckoo lays egg after incubation has begun

Bronze cuckoos have responded by inserting eggs during fairy wren laying period. such eggs are generally accepted and incubated.

However, when yuong cuckoos puses young wrens out of nest fairy wren abandon nest 40% of the time.

An important factor is the cuckoos ability to mimic begging call.

Question 37

what weapon does the european cuckoo chick have?

Answer 37

has the ability to make a call that sounds like a bunch of reed warbler chicks making the parents forage more.