Behavioral Ecology Flashcards
what is behavioral ecology?
study of the evolutionary basis for animal behaviour due to ecological pressures
what is the optimal foraging theory?
the basis for analyzing behavior as a compromise of feeding costs vs feeding benefits
three rules of OFT:
- preference for food with the greatest net energy gain
- feed more selectively when foods are abundant
- include low quality food only when profitable food are scarce
Pied wagtail and beetle size
When eating randomly, the pied wagtail is more likely to come across an 8mm beetle. But when the beetles get bigger their handling time increases. To maximize caloric intake per handling time the bird eats more 7mm bugs even tho they are less common.
sodium is the primary extracellular ion with the major role in…
- bodily fluid volume
- acid-base balance
- tissues pH
- muscle function
- nerve synapse
how is sodium lost?
- urine, defecation, sweating
terrestrial plants tend to be low in…
sodium
what are aquatic plants deficient in
calories
what are three constraints a moose has when choosing what percent of its diet are aquatic plants vs terrestrial plants?
- energy constraint (starve or survive)
- sodium constraint (need enough)
- stomach constraint (can only eat so much)
Regional variation on mineral contents of plants and its significance for migration by arctic reindeer and caribou:
Aquatic plants from the coast and inland were higher in _____ and _____ than terrestrial plants
Na, Cl
Regional variation on mineral contents of plants and its significance for migration by arctic reindeer and caribou:
this study supported the hypotheses based on salt hunger; namely that …..?
the primary reason to move in coastal regions was to compensate for Na deficiency in winter
bison migration
have to make large migrations from their grassy areas to salt licks to get efficient sodium, cobalt, copper
- there are more predators here but they still go
rules for optimizing foraging time
- concentrate foraging activity in the most productive patches and ignore patches of low productivity
- stay in the patch until the profitability falls to a level equal to the average for all foraging patches combined
food occurs in a ___ ___ and in patches of ____ size
patchy distribution, different
optimal foraging time experiment: bird opening lid
if the bird only took a short amount of time to open lid, might only stay a short while at the food inside (even if there was more food left)
- if the bird took a long time to open lid would stay a longer tim
foraging time and predation risk: mouse
if the mouse is starving it will risk predation… if the mouse isn’t very hungry it will stay safe and not look for food
territoriality
defense of an area and active exclusion of resource use by others through display, advertisement, or defense
home range
the area over which an animal travels in search of food/mates/resources which is not defended
T/F: home ranges are well-defended
false - they are not defended
T/F: territoriality is common in predators, most birds, fish, and social insects
true
name 6 factors that influence the size of a territory
body size, aggressive behaviour, habitat quality, population density, competition with others, ability to share resources
True/False: Black-capped chickadees and mountain chickadees often compete for territory
false (their territories often overlap; they fill different niches)
what happens when you remove some territories (ie. the great tit)
other tits moved into the free territory. the density stayed mostly the same
how is territoriality often expressed without direct confrontation?
olfactory signals, bird song
what are some benefits to having a larger territory?
increased food, shelter, reproduction
what are some costs to having a larger territory?
increased energy demands, defense, injury, vigilance
how do you find the optimum territory size?
benefit - cost
in asexual reproduction, offspring are ______ to the parent
genetically identical
what is asexual reproduction common in?
bacteria, unicellular eukaryotes (paramecium), plants
what are the best predictors of asexual reproduction in animals?
- short lifespan
- constant environment
what is sexual reproduction?
genes from two individuals combine to form new genotypes different from both parents
-> parents: AA x BB produce AB offspring
in changing or different environments…
new genotypes may have higher reproductive output than either parental genotype
what are the two categories of sexual reproduction?
- dioecious
- monoecious
what is dioecious
male and female organs on separate individuals
what is monoecious
male and female organs on the same individual
diocecious species usally have _____ sex ratio
equal
T/F: very few species are dioecious
false, most species are
what are the two types of monoecious species?
- simultaneous hermaphrodite
- sequential hermophrodite
what is a sequential hermaphrodite?
male and female reproductive parts develop at different times during growth
what is simultaneous hermaphrodite?
individual has both sets of reproductive organs at the same time
coral reef fishes are commonly _____
sequential hermaphrodites
what is panmixis?
unrestricted random mating - all opposite-sex individuals in a population are potential partners
most marine schooling fishes and some marine invertebrates are….
panmictic
in panmictic populations, sexes are usually_____
monomorphic
what is polygamy
multiple partners
polygamy is _____ is most species
widespread
in polygamous populations, sexes are usually _____
dimorphic - look different from eachother, males typically larger and more elaborate ornamentation
what is polygyny?
males mates with many females but females mate with a single or few males
polygyny is common in…?
- amphibians
- reptiles
- songbirds
- mammals
what happens in female defense polygyny?
individual males defend groups of females
-> common in elephant seal, seal lions, deer, primates
what happens in resource defense polygyny?
individual males defend resources which females seek out
-? common in fish, songbirds
what is polyandry?
females mate with many males but males mate with a single or few females
T/F: in polyandry, females compete for males and defend sources
true
in polyandry, ____ incubate eggs and become ____
males, sexually inactive
what is monogamy?
mating structure where individual has high fidelity to single partner
lifetime monogamy is ____ in most species
rare
T/F: monogamous species exhibit lots of dimorphism
false, sexes usually look similar
in monogamous pairings, the young require extensive ______
parental care
T/F: in monogamy, both parents are usually required to look after the young
true, young are very needy
what happens to a litter or brood if a parent in a monogamous species abandons it?
the entier litter/brood can be lost
mate choice
the tendency for an individual to be selective in whom they choose to mate w/
in most species, females invest more than males into ______ and are responsible for most _____
reproduction, parental care
fitness of offspring is influenced by their _____ and this is a function of ____
genetic makeup, who the female chooses to mate with
in most species, females on average choosier than males as the ____ of making wrong choice is greater than that of males
fitness cost
on average, male fitness is _____ by maximizing the number of ____ (ie mating w ___ females)
increased, fertilized eggs, lots of
males ____ to females and engage in ____ with other males for ____
advertise, competition, access to females
in most species, females make choices for mates based on _____
multiple criteria
what are the 7 criteria for mate choice?
- nuptial gift
- dominant/strong male preference
- handicapped male hypothesis
- parasite-free male hypothesis
- symmetrical male hypothesis
- display evaluation
- inbreeding avoidance
what is a nuptial gift
males provide gift (resources, food item, territory) to the females in order to solicit matings
-> females use the characteristics of the gift to determine quality of the male
male hanging flies bring ___ to females to solicit matings
insect prey
hanging fly: nuptial gift of prey item
bring gifts to females. the larger the gift, the longer a male is allowed to copulate with the recipient. larger copulation time leads to greater sperm transfer to the female.
what is the probability of a male thynnine wasp mating directly related to?
his ability to carry the heavy female to multiple flowers
when does the female thynnine wasp make her mating decision?
during flight
while the nuptial gift is a ____ for hanging flies, it is _____ for thynnine wasps
prey item, foraging opportunity
why do male songbirds defend their territory from other males during breeding season?
allows foraging opportunities for females and young
female songbirds evaluate male quality based on the ___ and ____ of his song as this is correlated with territory size
length, complexity
males differ in their abilities to ___ and ____ territory
establish, maintain
high quality males contribute to _____ and ______
parental care, territory defense
elephant seal: dominant/strong male preference
- female elephant seals were all breeding but some had a few more pups
- most successful male produced 90 pups and the 10th ranked produced none
female elephant seals show a preference for _____ males
strong/dominant
why are small damselflies/dragonflies equally likely to win their aerial combat?
larger energy reserves (ie higher fat content) not larger size, increases chances of victory
male damselflies engage in ____ with other males over ponds
aerial combat
what is the handicapped male hypothesis?
the expression of elaborate displays by males that are costly to produce and costly to maintain provide the female the greatest reliable information on the genetic quality of the male
who proposed the handicapped male hypothesis?
Zahavi
how do female widowbirds evalulate males?
tail length
female widow birds choose…
long tails as this should indicate the best genetic quality in that the male has survived despite handicape
who proposed the parasite-free male hypothesis?
Zuk and Hamilton
what are the 5 points in the parasite free male hypothesis?
- individuals differ in their susceptibility to disease such as parasites and pathogens, many of which can lead to mortality in young
- resistance to disease has a heritable component
- males with no parasites may have better immunological genes and improved physiological ability
- bright nuptial displays are physiologically costly to produce
- females choosing brightly coloured males are providing their offspring with advantageous genes that yield better resistance to disease
wild birds often have _____ that _____ the luster of their feathers
ectoparasitic lice, reduce
deloused males feathers had more sheen. females ____ them
preferred
Hamilton-Zuk hypothesis: Lizards on Caribbean islands
there was no association of parasite load with color either in a broad analysis or when correcting for phylogenetic relationships among the lizards
what is the symmetrical male hypothesis?
females prefer symmetrical males because they have a better genotype
excellent genotypes can ____ many ____ during embryological development and growth (______) and produce more _____ characterisitcs
correct, asymmetries, developmental homeostasis, symmetrical
minor errors during ____ and growth can result in slight asymmetries in structure (______)
embryological development, development instability
what can lead to slight asymmetries?
-stress
-pollutants
-parasitism
-homozygosity
-poor genotype
why is symmetry considered an “honest phenotypic indicator of genetic quality’?
symmetry reflects the inability of a genotype to buffer itself effectively against environmental stresses
female preference for symmetrical vertical bars in male sailfin mollies:
females have significant preferences both for bars per see and for males with symmetrical bars
T/F: the offspring of females with just a little bit of preference and the offspring of females with no preference have the same level of fitness
false, females with a little preference have more fit offspring than those with no preference
T/F: humans prefer perfectly symmetrical faces over slightly asymmetric faces
false, humans prefer slightly symmetrical faces
what is display evaluation?
females evaluate quality, complexity and coordination of display
what is inbreeding avoidance?
- all plant and animal species have one or more mechanisms to avoid inbreeding
- pheromones to detect homozygosity
many animal species detect _____ based on body odour (_____)
genetic kinship, pheromones
individuals have ~30 genes that code for a special class of ____ in cell ____ that are essential for out _____ system. this is the _____
proteins, membranes, immune, major histocompatibility complex
AA homozygotes produce _____ whilte a heterozygote can produce ______ (AB)
one type of protein, two different proteins
how many alleles can each gene in primates have?
55
______ appear to bind to specific recpetors and have _____
MHC molecules, distinct odours
where are olfactory receptors usually found?
nose, antennae
on average, females prefer males with the most ____ odour to themselves
dissimilar
the major process which increases genetic variability in small populations is….
immigration
the major feature of the Hamilton-Zuk hypothesis is….
bright plumage indicates good immunocompetence
what are the advantages for group living?
- increases food search efficiency
- increased capture efficiency
- increased detection of predators
- increased defence against predators
- selfish herd theory
seed detection in songbirds and fish detection in gulls is an example of_______
increased food search efficiency
larger hunting dog packs are capable of bringing down larger prey. does this mean that they net kj/dog/day increases linearly w pack size?
no, each dog typically gains a net 20,000kj/day until a certain pack size allows them to coordinate take downs of very large prey
at what pack size does the net kj/dog/day increase?
14
“mobbing” is an example of what?
defense against predators
what aspect of group living does the ‘many eyes theory’ relate to?
detection of predators
a pigeon living in a flock of 2-10 has what % chance of being eaten by a hawk?
55%
a pigeon living in a large flock has a decreased chance of being eaten by hawk because of the _______
many eyes theory
what is an example of mobbing?
flocks of smaller birds will harass a predatory brd
what is the selfish herd theory?
each individual is looking out only for themselves
another name for the selfish herd theory is…?
dilution effect
what are disadvantages of group living?
- sharing limited resources
- increased transmission or parasites
- conflict/stress
additional predators ______ optimal flock size
increase
the optimal flock size is the one in which…..
feeding is the highest per individuals
a decline in resources…..
decreases optimal flock size
what is life history?
set of rules and choices to an individuals schedule of reproduction
reproductive effort
the total allocations that an individual makes for reproduction
what are the categories of reproductive effort?
- r-selected
- k-selected
r-selected has….
- high numbers of offspring
- high population growth potential
- boom or bust cycle (unstable populations_
- max reproductive capacity (r)
k-selected has…
- low numbers of offspring
- low population growth potential
- stable populations
- usually long lived
- populations near carrying capacity (k)
T/F: reproductive effort categories are relational
true, rather than absolute
k-selected is a better strategy for when there are _____ resources
limited
mouse is r or k selected? what about bears?
r, k
what is semelparous
characterized by single reproductive episode before death
what is iteroparous
characterized by repeated reproductive episodes before death
what are examples of semelparous organisms?
cephalopods, most insects, salmon
what are examples of iteroparous organisms?
molluscs, most fish, most plants, amphibians, reptiles, birds, mammals
T/F: iteroparous organisms are k-selected
falses, categories of reproductive effort are relative not absolute
occurrence of parental care is generally absent in….
invertebrate taxa, sharks, amphibians, reptiles
amount of parental care _____ among similar groups
varies
types of parental care
precocial and altricial
what is altricial
young are helpless and requires parental care
what is precocial
young are independent at birth
_____ purposes that clutch size represents that ______ that the parent can successfully raises
Lack, max number of young
T/F: birds lay the max amounts of eggs possible to ensure the greatest reproductive success
falses, all birds lay fewer eggs than they are capable of having
clutch/litter size limits are found in ______
k-selected species
collared flycatchers: compared to normal clutch, chicks from artificially enlarged clutches had:
- reduced survival in first winter
- reduced egg production as adults
collard flycatchers: compared w normal clutch, parents from enlarged clutches had:
- reduced overwinter survival
- reduced egg production the following year
collared flycatchers….
feed their young until fledging
Canada Goose…
do not feed their young
Canada Geese: compared w normal clutch, chicks from artificially enlarged clutches had:
survival similar to normal clutch
Canada Geese: compared w normal clutch, parents from artificially enlarged clutches had:
- delayed molt/migration
- reduced weight subsequent year
- female bred later than normal on subsequent year
clutch size corresponds to…
the max number of offspring that the parents can rasies without a net reduction in their future reproductive effort
in most plants anf fish, fecundity (# of eggs) is ______ to body size
positively correlated
when is it useful to reproduce as early as possible?
in the absence of predators
when is it useful to delay reproduction?
abundance of predators
the best strategy for reproduction is the one which
replaces faster
early reproduction can be detrimental because
it often stunts the growth of females
there is a trade off between present ____ and future____
reproductive output, reproductive success
r-selection:
rapid development
high reproductive rate
early reproductive age
small body size
k selection
slow development
low reproductive rate
late reproductive age
large body size
r selection p2
short length of life
semelparous reproductive type
high mortality survivorship of young
k selection p2
long length of life
iteroparous reproductive type
low mortality survivorship of young
r selection p3
weak competitive ability
variable, usually well below carrying capacity population size
good dispersal activity
disturbed type of habitat
k selection p3
strong competitive ability
constant population size
poor dispersal activity
not disturbed type of habitate
