Describe how birds "see" their world using the typical plan for the vertebrate eye
We share with birds many commonalities of vision, , including retinal organization and color vision. But, birds can see things we cannot,
greater or lesser overlap of vison between two eyes, better vison depth perception but less view of view range.large eyes relative to skull size so better vision, Birds have 4 cones which allows us to see ultra violet light,
Articulate how sound is perceived by a Barn Owl
WHole head designed for listening, their head is shaped like a satile dish to detect sound, channals sound towards ear, one ear higher than other, can distinguish heigh and direction, depending on when the sound arrives and which ear hears first.
Give specific ecological examples of species that excel in using various senses
Owls excel in hearing
kiwis great sense of small and tactile sensation in rictal bristles
Wilsons snipe - tactile sensation in bill
Define intelligence and articulate a conservation ethic based on sentience and intelligence
Having a higher mental capacity, memory, launguge, being able to learn and apply knowledge and skills
Complex behaviors associated with well-developed brains evoke strong empathy among humans. This is especially the case with vertebrates that share with humans the ability to communicate in complex ways.spawn interesting issues regarding moral obligations of humans to other living organisms.
Describe how and why birds produce sounds.
Birds produce sound in a variety of ways, including their feathers, bill, feet and syrinx.
Birds communicate with one another principally through visual and acoustic signals. to convey information to competitors and potential mates.
Distinguish between songs and calls
Songs typically are:
A complex series of repeated notes
Given my a male (some females do sing...)
Produced during the breeding season
Function to defend a territory and/or attract a mate
Calls are:
Simpler in structure
Depending on the call, uttered in specific contexts by males, females, young, etc.
Sometimes produced year-round
Varied in function (e.g., begging calls of young in the nest; alarm calls of individuals responding to a predator; courtship calls that precede copulation
Explain in detail (i.e., elements, timing) how song learning takes place using the model proposed for White-crowned Sparrow
Genetic template: individuals hatch with a predisposition to decipher the song of their species and not confuse it with that of other songbirds. Mistakes sometimes happen!
Sensory (critical) period: Learning requires memorization! And this is the interval from 10-50 days in the life of a young sparrow when it must hear and memorize conspecific song. If he can't hear other birds sing (i.e., because he's isolated in a cage and kept from hearing them...), then song develops abnormally. How might a female sparrow learn its song?
Sensorimotor period: 150 days post hatchThis represents the phase in life when a male practices what he memorized during the critical period. If he cannot hear himself sing (i.e., because his auditory nerves have been severed), then song develops abnormally
Articulate how a dialect develops and its significance in conservation
diversity of song across a population not genetically controls, what birds are exposed too
sometimes the only difference between close looking species are their dialect, if a mate can not recognize a song then bird can not mate, helps define species if they have song learning or innate dialect
Discuss the role that song learning plays in speciation among different groups of bird.
finches hydriation
song reproductive barrier
difference in song barrier even though can repro
Describe how mimicry differs from other types of song learning, and explain some of the evolutionary explanations for its development
not constrained by just learning song of own species, more plasticity, mimiery things other than birds, extension of song learning. Manipultion bring birds in, scare them away, sexual selction - more complex, tools for getting leg up on competition, species recognition- males sing song that mimics host species
Provide a detailed description of how a fertilized egg is formed, including the timing of events surrounding formation of the components of an egg in histologically distinct segments of the oviduct
copulation preceded and followed by courtship behavior
Ovary with individual ova
• Ovum erupts from follicle
• 1 each 24 hr
• Ovum = unfertilized egg + yolk
Infundibulum
(aka Ostium)
• 20 min.
• Opening grasps ovum
• Sperm fertilizes egg
MAGNUM
3-4 hr
• Fertilized ovum with yolk
• Albumen deposited
• 90% water & 10%
protein
ISTHMUS
1 hr
• Outer & inner shell
membranes deposited
• Encapsulates albumen,
yolk & embryo
UTERUS
• ~20 hr
• Dilated region
• Shell gland deposits
calcareous shell
• Coloration & pigments
added
CLOACA
• Short duration
• Egg held before laying
Explain the value to humans of understanding bird reproductive biology
Bird reproduction is essential for maintaining bird populations. it is important to know clutch size, timing of egg laying to make proper management decisions
Define incubation, including its three elements
Process by which eggs
are kept at temperatures
suitable for development
in a humid environment
that is regularly changed
to allow for gas exchange
and during which eggs are
turned regularly
temperature, humidity, and turning
Identify and describe "exceptions to the rule" in the definition
Birds are burry their eggs
Define clutch size.
Number of eggs laid by a
single female in a
reproductive attempt
(nest)
1. Brood parasites (cuckoos,
cowbirds)
2. Cooperative breeders
(anis, woodpeckers)
Explain Lack's hypothesis. Describe some of the reasons that this hypothesis is not always supported by data on real birds
hypothesized that natural selec- tion has caused clutch size in birds to evolve toward that which produces the most surviving offspring.
X = clutch size
• Y = # hatched or survival
probability of young
from clutches of
different size
Combination of clutch
size & parental ability
to feed increasing
numbers of young
• Yields clutch size
curve
In many cases, observed
clutch size is less than
optimal
Compare and contrast the ways that food resources control clutch size of individual females in precocial and altricial species
Individual females lay as
many eggs as they are
energetically capable of
producing
• Altricial – low yolk
investment
• Nidicolous young
• Naked, eyes closed
• Chicks fed in nest by
adults • Precocial – high yolk
investment
• Nidifugous young
• Downy, well developed
• Chicks feed themselves
Altricial; nidicolous; nidifugous; precocial
• Altricial – low yolk
investment
• Nidicolous young
• Naked, eyes closed
• Chicks fed in nest by
adults • Precocial – high yolk
investment
• Nidifugous young
• Downy, well developed
• Chicks feed themselves
Explain how development influences mating system
constraints, whether altricial and precocial effects what parental duties have to be done, some parental duties can be shared by other sex- mammals females have to feed and carry their young to term but having eggs eliminates females that requirement
Give specific examples of species that illustrate the various mating systems
MONOGAMY
1 f + 1 m
bi parental, extra pair mate uncommon
1. Lifetime – swans, geese, wrentit
2. Annual –penguins, some
shorebirds, raptors
POLYGYNY
northern pintails
POLYANDRY
1 f + muli m
phalaropes, females take on male duties
PROMISCUITY
no pair bond, no resources, or territory, mate grauding, or male parental care- sage grouse (display, mate, done)
Describe how individual species vary in expression of a mating system under the influence of patchy resources and availability of mates.
mating systems not conserved in lineages, change rapidly, relates to niches of animals, nutrients, and easily accessible supports polygamy, food lower in nutrition or harder to acquire, monogamy
females' decisions to take an unpaired or paired male. in responce to environmental conditions, territory dense contentrations of patch of resources polygamy females. like. less resources monogamy
Explain cooperative breeding, and explain the details of the evolutionary theories about its development that we discussed in class
In a few hundred species of bird, individuals act "cooperatively" to rear young in groups. These mating systems consist of two kinds: 1) helper-based systems, in which close kin assist the breeding pair; and 2) communal breeding, in which groups of males and females breed together, albeit unequally and where there is often more conflict. Co-operative breeding is a system where a pair of birds is helped with incubation and rearing their chicks by other birds of the same species. breeding pair benefits by being able to raise more young, helpers do occasionally breed, practice, opportunities to breed, kin selection (Shared genes with kin, ecological constraints