CHAPTER 35: Behavioral Adaptations to the Environment

Sections 35.1 – 35.3: The Scientific Study of Behavior

• Important to Know: 

  • These three sections are the most important for application.  You should be able to identify these vocabulary terms and situations before you study application on this chapter.  There’s potential for Marton to use application questions in the tentative test (whenever it is), so STUDY this.

• Behavior: an action carried out by muscles or glands under the control of the nervous system to an environmental cue

  • the sum of an animal’s responses to both internal and external environmental cues

  • can apply to more than just observable behavior

    • chemical communications (e.g.: secreting a chemical that attracts mates)

    • learning (which itself is not a behavior but a factor that changes it)

• Behavioral ecology: the study of behavior in an evolutionary context

  • studies how an animals develops, evolves, and contributes to its survival and reproductive success

• Proximate questions: asking for the immediate reason for a behavior; how it is triggered by stimuli, physiological and anatomical mechanisms, or underlying genetic factors

  • Stimuli: environmental cues that cause a response

  • E.g.: “How do voles choose their mates?”

    • generally a HOW question

  • Proximate causes: the answers to proximate questions about the immediate mechanism(s) for a behavior

• Ultimate questions: asking for the reason a particular behavior occurs

  • E.g.: “Why does natural selection favor the change in mating behavior?”

    • generally a WHY question

  • Ultimate causes: the answers to ultimate questions about the reasoning for a certain behavior

• Innate behavior: behavior genetically hardwired in an organism that is triggered by stimuli (or stimulus)

  • occurs regardless of experience; present at birth; practically instinctive behavior

  • innate behaviors occur in all animals

• Fixed action patterns (FAPs): an unchangeable series of actions triggered by specific stimuli/stimulus

  • Consider a coffee vending machine: You feed money to it and press a button, which makes it perform a series of actions.  A cup drops into place; releases a specific volume of coffee; adds cream; adds sugar.  Once the money triggers these mechanisms, the machine completes the entire process.

    • In FAPs, the money is the stimulus, making the coffee machine do a series of actions (the coffee machine can be an animal).  

      • FAPs can still occur even if a part is missing

        • if the cup is missing, the coffee will still pour, as well as the cream, and sugar.  (They don’t care.)

• a FAP is an innate response to a certain stimulus

• Genes govern learning, memory, internal clocks, and courtship/mating behaviors

  • proteins encode for behaviors

• Phenotype depends on the environment and genes

• Sex can be determined by the environment

  • the temperature of the egg during embryonic development

• Environment can influence behavior

  • behavior is the product of both genetic and environmental factors

    • For example …

      • “low-interaction” Norway-rat mothers who do not interact with their offspring as much make her pups more sensitive as adults to stimuli that trigger the “fight-or-flight”

      • vice-versa; “high-interaction” Norway-rat mothers who interact with their offspring more make her pups more relaxed in stressful situations as adults

Sections 35.4 – 35.11: Learning

• Learning: a modification of behavior as a result of specific experiences

  • i.e.: environmental conditions, social conditions, etc

• Habituation: the loss of a response to a stimulus after repeated exposure

  • either because the stimulus conveys little information or conveys no information at all

  • habituation increase fitness by allowing an animal’s nervous system to to focus on stimuli signaling food, mates, or real danger—rather than waste it on a vast number of stimuli that are irrelevant to survival/reproduction

    • E.g.: scarecrows and birds

      • the scarecrow can scare off birds, but if it is in a certain area for too long, the birds will think it is safe and habituate it.  moving the scarecrow periodically, however, will prevent this

• Imprinting: learning that is limited to a specific time period in an animal’s life and that is generally irreversible

  • For example …

    • (in a parental-offspring relationship) a young duckling considers the first moving object they see as their mother.  in a NORMAL scenario, they will see their mother duck, and consider it their mother.  in an ABNORMAL scenario, they will see a human, and consider it their mother (or anything that moves).  this is not good.

    • (in an environment relationship) newly hatched salmon imprint on the complex mixture of odors unique to their stream.  later in life, as adults, they can find their way back to their home stream to spawn.  

      • all of these are IRREVERSIBLE

  • Sensitive period: the limited phase in an animal’s development where it can learn certain behaviors

  • imprinting provides a way for such behavior to become more or less fixed in an animal’s nervous system

• biologists used sandhill cranes as surrogate parents for whooping cranes

  • the whooping cranes imprinted on the surrogate parents as a species to mate with; whooping cranes had no interest breeding with other whooping cranes

• Kinesis: random movement in response to a stimulus

  • can be merely starting or stopping, changing speed, or turning more or less frequently

    • E.g.: Sow bugs: they perform kinesis by being more active and moving about randomly, but only in dry areas.  when they reach a more favorable environment (a moist area), kinesis is decreased so they are kept there

• Taxis: a response directed toward or away from a stimulus

  • positive taxis: directed toward

    • E.g.: salmon exhibit positive taxis in the current; they swim against the current because food is more likely to come

• negative taxis: directed away

• Spatial learning: where animals establish memories of landmarks in their environment that indicate locations of food, nest sites, prospective mates, and potential hazards

  • E.g.: a female digger wasp builds a nest next to pinecones.  when she leaves the nest, she’ll remember her nest is next to pinecones.  if someone moves the pinecones, and she’ll return back to the area, the digger wasp will assume her nest is next to the pinecones.  it is not, because the pinecones were moved.

• Migration: the regular back-and-forth movement of animals between two geographic areas

  • linked to spatial learning

• Associative learning: the ability to associate one environmental feature to another

  • the animals learns to link a particular stimulus to a particular outcome, basically

    • E.g.: telling a dog “do you want to go for a WALK?” — the word WALK can be associated with going outside, and dogs like to go outside, so the outcome is typically positive, which makes the dog approach you

• Trial-and-error learning: an animal learns to associate one of its own behaviors with a positive or negative effect

  • memory is key to all associative learning

  • if the effect is POSITIVE, the animal will continue to repeat the behavior

    • E.g.: a dog sits when you command it and receives a treat afterwards.  the dog will associate it as a POSITIVE effect.  the dog will continue that behavior

  • if the effect is NEGATIVE, the animal will avoid the behavior altogether

    • E.g.: if a dog bites a porcupine, the porcupine’s sharp quills will stab the dog, making it injured.  the dog will associate it as a NEGATIVE  effect.  the dog will avoid that behavior.

• Social learning: learning by observing the behavior of others

  • E.g.: Vervet monkeys give distinct calls when seeing certain predators

    • seeing a leopard = a loud barking sound

    • seeing an eagle =  a two-syllable cough

    • seeing a snake = a “chutter”

    • upon hearing a particular alarm call, they behave based on the call

      • leopard = running up a tree

      • eagle = look up

      • snake = look down

• Cognition: the process carried out by an animal’s nervous system to perceive, store, integrate, and use information gathered by the senses

  • many animals are capable of categorizing physical objects in their environment according to concepts such as “same” and “different”

• Problem solving: the process of applying past experiences to overcome obstacles in novel situations

  • highly developed in some mammals (dolphins and primates)

  • E.g.: if a banana is hung high up, and there are boxes on the floor, a chimpanzee will stack the boxes in order to get the banana.  (cute asf lmao)

Sections 35.12 – 35.16: Survival and Reproduction Success

• Nutrition is essential to an animal’s survival and reproductive success

• Natural selection refines behaviors that enhances the efficiency of feeding

• Foraging: food-obtaining behavior and mechanisms any animal can use to discover and capture food

  • Generalist animals

    • will eat anything

      • E.g.: crows eat anything readily available such as plants, animals; they can eat anything alive or dead

  • Specialist animals

    • eat only specific and extreme food

    • are vulnerable to habitat loss because they are restricted to certain areas

      • E.g.: koalas only eat the leaves of a few species of eucalyptus trees

  • Search image: the mechanism enabling an animal to find particular foods efficiently 

    • in simple terms, people look for a certain item on a kitchen shelf by scanning rapidly for a package of certain size and color rather than reading all the labels

    • if the favored food item becomes scarce, the animals develops a different search image for a different food item

• Optimal foraging theory: an animal’s feeding behavior should provide maximal energy gain with minimal energy expense and minimal risk of being eaten while foraging

  • in an analogy, an artist should not waste all his energy on studying mathematics if it does not benefit his field.  instead, he should study watercolor or sculpture-making since it provides a great benefit.

  • E.g.: wagtails catch medium flies rather than small and large flies, simply because they are either hard to catch or do not give much energy

  • foraging in groups reduces the individual’s risk of predation

    • hunting in groups improves success

• Signal: a stimulus transmitted by one animal to another animal

  • interactions between animals depend on some form of signaling between the participating individuals

    • the more complex the social organization of a species, the more complex the signaling required to sustain it

      • For example …

        • humans rely heavily on technology to inform them and others of events; news sites such as CNN and ABC; apps such as Snapchat and Tiktok

        • nocturnal animals do not rely on visual displays because it is too dark to recognize them in the first place.  instead, they use odor and auditory signals

        • diurnal animals (active in daytime) use visual and auditory signals because they can recognize them because of the environment they are accustomed to (daylight)

• Communication: the sending of, reception of, and response to signals

• This section (35.15; Mating behavior often includes elaborate courtship rituals) is generally useless in terms of vocabulary (because it lacks it).  This is a repeat of 13.15, so read that.

• Promiscuous mating system: no strong pair-bonds between males and females

  • For example …

    • female chimpanzees mate with multiple males without forming long-term bonds, which leads to sperm competition → increases both genetic diversity and population size

    • free-ranging dogs (undomesticated) mate with other dogs opportunistically without much bonding → increases both genetic diversity and population size

• Monogamous: a bond between one male and one female, with shared parental care

  • For example …

    •  most newly hatched birds cannot care for themselves and required a large & continuous food supply → survival chances are higher with monogamous because both parents can supply resources

    • (human) newborns cannot fend for themselves and require care from both parents → survival chances are higher with monogamous parents because both parents can supply resources. (though, it’s important to note how adaptable and flexible humans are to the point where only one parent can suffice.)

• Polygamous: an individual of one sex mating with several of the other

  • For example …

    • in lion prides (a family unit of lions), a few dominant males mate with multiple females in the group.  the dominant male will control the group of females he impregnated.  this will happen until the dominant male is challenged → increases the chances of offspring dominating the next generation and ensures genetic quality

    • male red-winged blackbirds defend a territory that includes nesting sites for several females.  within his territory, the male mates with all of the females → high reproductive success

• Parental care involves significant costs, including energy expenditure and the loss of other mating opportunities

• Abnormal behaviors (i.e.: lackadaisical territorial defense, salamanders ignoring mating cues, etc) are linked to endocrine-disrupting chemicals

• Endocrine disruptors affect vertebrate endocrine systems by mimicking a hormone or by enhancing or inhibiting hormone activity

  • For example …

    • some male fish attract females during the breeding season by defending territories.  when exposed to pollutants that mimic estrogen, nest-guarding behavior drops.

  • these chemicals pollutants enter ecosystems from a variety of sources: 

    • discharge from paper & lumber mills; and factory wastes such as dioxin and PCBs

    • agricultural pollutants such as DDT and pesticides

    • birth control pills and other hormones

Sections 35.17 – 35.23: Social Behavior and Sociobiology

• Social behavior: any kind of interaction between two or more animals, usually of the same species

  • E.g.: mating behaviors, aggression, cooperation, group migration, & large feeding groups

• Sociobiology: they study of how social behaviors are adaptive and how they could have evolved by natural selection

• Territory: an area usually fixed in location that one or more individuals defend & exclude from other members of the same species

  • typically used for feeding, mating, rearing young, or a combination of aforementioned

• Agonistic behavior: threats, rituals, and sometimes combat that determine which competitor gains access to a specific resource (i.e.: food, mates, territories, etc)

  • is not usually violent in terms of “to death”, more-so threatening and intimidating to specify the “stronger” one

  • For example …

    • rattlesnakes wrestle over access to a mate.  they do not kill each other, or use any harmful resource equipped to their characters, because both would die.  instead, they push and shove each other, which would tire one out.  the winner is the one who has more energy than the other.

• Dominance hierarchies are maintained by agonistic behavior

• Dominance hierarchy: a ranking of individuals based in social interactions

  • For example …

    • several unfamiliar hens peck each other to establish a “pecking order”.  the alpha is the one who has established that they are the strongest; therefore, they have first access to resources such as food, water, and roosting sites.  the beta is second line subdues all the others except the alpha.  this is repeated down to the lowest hen.

• Altruism: behavior that reduces an individual’s fitness while increasing the fitness of others in the population

  • meaning, sacrificing your own wellbeing for the sake of others

  • For example ..

    • a worker bee stings an intruder to prevent it from going further into the hive, but dies in the process → increases survival chances of other bees

• Inclusive fitness: an individual’s success at perpetuating its genes by producing its own offspring and by helping close relatives to produce offspring

• Kin selection: natural selection favoring altruistic behavior that benefits relatives

• This section (35.22: Jane Goodall revolutionized our understanding of chimpanzee behavior) is generally irrelevant to me.

• This section (35.23: Human behavior is the result of both genetic and environmental factors) is generally irrelevant to me.