Chapter 8: Behavioral Ecology Flashcards
(39 cards)
Ethology: the basic study of _____ _____
animal behavior
By focusing on events that take place during an animal’s lifetime, this approach (a “_____ ” question about behavior) seeks to explain behaviors in terms of their _____ or _____ causes.
how
immediate
proximate
By addressing previous events that influenced the features of an animal as we know it today, this approach (a “_____ ” question about behavior) seeks to explain behaviors in terms of their _____ or _____ causes.
why
evolutionary
ultimate
It is usually a _____ to assume that _____ are under the control of one or few _____ . It also _____ to assume that an individual that has an _____ associated with a certain behavior will always perform that behavior.
mistake behaviors genes wrong allele
Instead 2 individuals with _____ alleles may behave _____ . Individuals often _____ their behavior when in different environments. Genes affect behaviors and natural selection molds behaviors over time.
identical
differently
change
Optimal foraging theory best describes the foraging behavior of animals that feed on _____ prey and applies less well to animals feeding on _____ prey
immobile
mobile
P=E/t
Items with high _____ (P) are generally preferred
E = _____ _____ _____ , i.e., energy gained minus energy invested in obtaining & processing the food
t = _____ _____ & _____ _____ invested in obtaining & processing the food
profitability
net energy value
encounter time & handling time
Optimal foraging proposes that animals will maximize the amount of energy required per unit of feeding time. Optimal foraging relies on the assumption that _____ _____ acts on the _____ _____ of animals to maximize their rate of energy gain.
natural selection
foraging behavior
If an animal if foraging optimally and has a choice between two equally abundant food items, it will select the food with the _____ _____.
higher P.
Net energy gained = (Total energy obtained) – (Cumulative energy investment) Drops off as animal cannot carry nor ingest more
At first, the total amount of energy that an animal obtains from its food _____ _____ with the effort it invests – that is, with the time and energy it spends searching for, capturing, subduing, and consuming food.
At some point, however, a further increase in foraging effort provides relatively little additional energy, and the net energy gain begins to decrease. Several factors may cause this _____ , including a limitation on how much food the animal can carry or ingest.
increases rapidly
decrease
Marginal Value Theorem as applied to _____ of _____ _____ :
Within a patch, the marginal value for longer time has _____ returns
Slopes of straight, solid lines = Energy gained / time
Tangent maximizes profitability (slope) & determines _____ giving up _____
profitability of foraging patches
diminishing
optimal
time
Marginal Value Theorem can be used to evaluate the influences of distances between _____ , the quality of the _____ in a patch, and the animal’s energy _____ _____ on the giving up time.
patches
food
extraction efficiency
Marginal Value Theorem has also been extended to other “giving up” problems in behavioral ecology, including how long to _____ and when to _____ guarding a nest and seek other mates.
copulate
cease
Marginal Value Theorem assumes that a foraging animal will _____ patches containing varying amounts of food. The animal’s rate of energy gain in a patch is initially _____ but _____ as the animal _____ the food supply in the patch. The time the animal spends in a patch should optimize its rate of energy gain.
encounter
high
decreases
depletes
Foraging (and other) decisions can be modified by _____
Prey sometimes _____ their _____ of predators to those predators. E.g., stotting / pronking
predators
communicates
awareness
There is a wide variety of ways that prey seek to prevent attack once they are seen.
When threatened some prey make sudden movements or place their body in positions that startle a predator. Some prey send predators a signal, in effect conveying, “____ ____ ___, I’m faster than you, ____ ____ ___ ____ ____.”
“I see you,
so don’t bother to attack me.”
Members of a ____ can enjoy higher reproductive success than ____ ____
As the number of individuals in a group increases, the chance of being the one attacked decreases.
group
solitary individuals
Main Advantages of living in a group: access to ____ , protection from ____ , and improved ____ success.
Other benefits include gain access to good breeding sites or abundant supplies of food, and shared responsibilities if feeding and protecting the young.
mates
predators,
foraging
Main Disadvantages of living in a group: greater ____ ____ , more ____ for food, and higher risk of ____ .
energy expenditures
competition
disease.
Groups should be a size at which the benefits of belonging to a group exceed the costs.
Optimal size – the size at which the net benefits received by its members are maximized; the observed group however can be ____ than the optimal size
larger
Sexual selection is a process in which individuals with certain characteristics gain an ____ over others of the same sex solely with ____ to ____ ____ .
Sexual selection can be considered competition for gametes.
advantage
respect to mating success.
Competitive males and choosy females result from greater female investment in offspring;
the reverse occurs when there is greater male investment in offspring.
In species in which ____ invest more in their offspring than ____ do, we would expect ____ to be choosy and ____ to compete for the right to mate with females.
Since ____ invest relatively little per offspring produced, we would expect that ____ could produce more offspring during their lifetime than ____ could.
females
males do
females
males
males
males
females
direct benefits
nuptial gifts
gifts of food, help in rearing the young, or access to a territory that has good nesting sites, abundant food, or few predators.
