chapter 12 Flashcards
what are the two types of antipredator behavior
Those that help prey avoid detection by predators
Those that function once a prey encounters a predator.
pros of avoiding predators and how do animals avoid predators
they decrease not only the probability of being captured and eaten but also the costs associated with fleeing or fighting back
We will examine three ways
that animals can avoid their predators: (1) blending into the
environment, (2) being quiet, and (3) choosing safe habitats.
what do prey do when they encounter a predator (5 things)
- fleeing
- approaching a predator to obtain information
- feigning death
- signaling to the predator
- fighting back
animals that were far from their territory fled…
faster
animals involved in foraging mating or fighting were (faster or slower) to flee from predators
slower because they were distracted and less on alert for predators
does size and speed also affect prey’s perception of risk
The predator’s size and speed and the directness of its approach affected the prey’s perception of risk.
are armored animals more or less likely to flee from a predator
less likely
does learning impact fleeing behavior
yes, prey typically flee at a greater distance as a function of experience with predators
can embryos adjust to predation
Yes, ex.: If terrestrial predation from snakes and wasps is weak, eggs hatch late in the season
First, it lengthens the time that the eggs/embryos are in a low-predator terrestrial habitat
Second, such late hatching allows the embryos to grow to a size that lowers the levels of fish predation once the eggs finally hatch and the tadpoles fall into the water
why would an animal approach a predator
allow prey to gather important information about putative
predators and reduce their chances of mortality. This sort of behavior has been extensively documented in vertebrates, particularly in fish, birds, and mammals
this can lead to 3 outcomes:
1. prey retreating
2. prey rejoining a social group of conspecifics nearby
3. an escalation in which prey actually attack the predator
Three non–mutually exclusive benefits of approaching a predator.
- decrease the current risk of predation.
- allow gazelles to gather information about a potential threat.
- serve to warn other group members of the potential danger associated with predators
costs to approaching behavior
lost time/energy
This time could otherwise be devoted to other activities—for example, foraging, mating, resting—and so it represents a real opportunity cost to the animals
tonic immobility
An insect falls and then remains frozen, absolutely still. part of faking or feigning death
did good flyers feign death for shorter or longer
shorter
beetles that engage in a lot of death feigning have what amount of dopamine
higher amounts of dopamine
what are two ways that prey transmit info to a predator to deter an attack
(1) warning coloration in monarch
butterflies (ingestion of milkweed, makes predator ill; birds now associate monarch color with illness)
(2) tail flagging in ungulates
what functions does tail flagging serve
warn conspecifics, both kin and nonkin, about the presence of a predator
tighten group cohesion, which might make predation less
likely
increase probability that group-related foraging and antipredator benefits are present in the future
Signal to the predator that it has been sighted and should abandon any attack
Entice the predator to attack from a greater distance, which may result in a failed attempt at capture
Cause other group members to engage in various antipredator activities, confusing the predator, and making the flagger less likely to be the victim of an attack
Serve as a sign for appeasing dominant group members, and only secondarily play a role in antipredator behavior
fighting back chemical defense
toxic sprays harm predators but not the prey releasing them. when attacked at the front they spray forward; when attacked from the back they spray from behind (beetles)
Do squirrels prefer larger or smaller items when faced with predation
larger items
what is the best way to study how selection operates on antipredator behaviors
Comparing a single species in populations with and without a particular predator
