Brood Parasitism and Cooperative Breeding

Flashcards about brood parasitism and cooperative breeding in birds.

Besides parental care, name two strategies some species of birds have evolved.

Brood parasitism and Cooperative breeding.

In brood parasitism, __.

Neither parent cares for the young

In cooperative breeding, ___.

Parents are assisted by relatives in caring for young

Brood parasitism involves __.

Laying eggs in nest of another female

Laying eggs in another female's nest __.

Reduces parasite’s cost of raising young at expense of host

Intraspecific brood parasitism means __.

Within-species brood parasitism

Interspecific brood parasitism means __.

Among-species brood parasitism

The stages in the evolution of obligate interspecific brood parasitism are ___.

Intraspecific brood parasitism, Facultative interspecific brood parasitism, Obligate interspecific brood parasitism

Intraspecific brood parasitism is __.

Common in waterfowl

An example of intraspecific brood parasitism is __.

Egg-dumping

An example of Facultative interspecific brood parasitism is __.

Black-billed Cuckoos and Yellow-billed Cuckoos occasionally parasitize each other.

Adaptations of obligate interspecific brood parasites are __.

Large clutch size, Thick-shelled eggs, Egg mimicry, Fast growth rate, Removal of host’s eggs, Plumage and mouth-color mimicry by parasitic nestlings

Egg mimicry involves __.

Different populations of Common Cuckoo parasitize different hosts and have evolved eggs to match host species

Experienced host species __.

Have evolved inherited responses to brood parasites

Naïve host species __.

Have not evolved such responses

Adaptations of experienced hosts include __.

Ability to recognize parasitic egg, Rejection of parasitic egg, Burial of parasitic and host eggs, Nest abandonment

Double-brooding mitigates effect of nest parasitism on host species because __.

Parasitism rates decline steeply as the breeding season progresses, so second nesting attempts are much less likely to be parasitized than initial attempts

Humans modified landscape and ___.

Opened clearings in eastern forests

BHCO invaded eastern forests and brought into contact with naïve species because __.

Naïve species have not evolved responses to parasitism

The ecological impact of the Brown-headed Cowbird includes __.

Reproductive success of Naïve host species so reduced that it leads to population declines of hosts

Cooperative breeding involves __.

Care of offspring shared by members of stable social group

Helpers are beneficial because __.

Helpers increase reproductive output of the group (and fitness of parents)

Cooperative breeding evolves when __.

When resources are scarce and unpredictable, when young adults are unlikely to obtain their own territories

Territorial saturation (and thus cooperative breeding) more common because __.

Breeding success of Acorn Woodpecker depends on cache of acorns, which can only be defended by a family group

Delayed dispersal in cooperative breeders occurs because __.

Young adults delay dispersal and breeding, To inherit territory of older adult (often a parent), To increase lifetime reproductive success while waiting to acquire territory by helping to raise relatives (often siblings)

Hypothesis 1 states __.

With more helpers present, females invest more in reproduction to maximize output under favorable conditions

Hypothesis 2 states __.

with more helpers present, females invest less, increasing their own survival, and helpers will offset their lower investment

A 2017 study found __.

Females invested less in reproduction by laying smaller eggs when more helpers were present

Cooperative breeding evolves:

● When resources are scarce
and unpredictable
● When young adults are
unlikely to obtain their own
territories

Territorial saturation (and thus cooperative breeding) more common:

• Among permanent
  residents than among
  migrants
  ● In the tropics than in the
  temperate zone