Biology 192 Exam 3

Imprinting

Critical sensory period. Baby animal fixes its attention on first face it has a visual or auditory experience with. Within first 24 hours of birth.

Associative Learning

making associations based on experiences

A predator learning to avoid certain prey is an example of…

Associative Learning

Innate Behavior

Behaviors that require no learning. They are just known.

Monarch butterfly is high in toxic milkweed plant chemical. Blue Jays feed on monarchs and become sick. Blue Jays have learned to avoid monarch butterflies. This is an example of what learned behavior?

Associative Learning

Social learning

learn how to solve problems from watching others

meerkats learn to be watchful of predators by observing older individuals in their pack. What learned behavior is this?

Social learning

Cheetah cubs watch their mother and learn how to hunt. This is an example of which learned behavior?

Social Learning

Altruism

Type of behavior considered to be selfless. An act that favors another individual at some cost to self.

Reciprocal Altruism

no genetic benefit for the behavior. Individuals involved are non-relatives

Kin selection

individuals involved are relatives. Some kind of genetic/fitness benefit.

Reciprocal Altruism requires what?

the animal that was helped MUST reciprocate later and if they don’t, the helping animal will punish the helped individual by withholding food or will stop doing the altruistic act.

Example of Reciprocal altruism

(unrelated individuals) Wolves in a pack sharing food, deer help feed non-offspring, primates grooming each other.

Conditions for reciprocal altruism

1. Must be in a long-term relationship with the group

2. individuals must have memory

3. individual recognition

4. individual involved must reciprocate the act

5. Punishment associated with non-reciprocation (this is called tit-for-tat strategy)

Tit-for-tat strategy

Individual A does something nice for individual B but indiv. B does not reciprocate → Individual A will not share food anymore with indiv. B

If individual B doesn’t reciprocate for a long time and individual A stops helping individual B, but the individual B start reciprocating what can happen?

Individual A can return to cooperation once reciprocation starts occuring

Kin Selection example

“Aunt” lion helping raise her sister’s cubs. Pied Kingfishes help raise younger siblings.

Overall fitness=

inclusive fitness

Inclusive fitness has 2 components

1. Direct fitness (DF): fitness gained when produce own offspring

2. Indirect fitness (IF): fitness associated with helping Kin to raise their offspring

INC = DF + IF

Inclusive fitness = direct fitness + Indirect fitness

For kin selection to evolve, some conditions must be met:

• INC (altruism) > INC

• DF + IF > DF + IF (IF = 0) → not doing any altruistic acts

Population

individuals of the same species living in the same area at the same time. Must be able to interbreed.

Population Ecology

study of populations in relation to their environment

Individuals influenced by similar environmental conditions (resources)

Population

Clumped dispersion pattern

populations spread out in environment in clumps. Most common dispersion pattern in nature.

reasons for clumped dispersion pattern

Sea stars clumped together where food is abundant is an example of what population dispersion pattern?

Clumped dispersion pattern

School of fish → protection, works by confusing a predator

Clumped population dispersion

Herd of elephants (travel in social groups)

Clumped dispersion population

flowers in a field - species will drop seeds right where they are going

clumped population dispersion

Uniform Dispersion pattern

Indiv. of a pop are equally spaced. This is b/c of direct interaction b/w indiv. Territoriality.

King Penguins use this type of dispersion method to be close enough for warmth but far enough away to have their own territory

Uniform dispersion example

dessert shrubs and redwood trees pace out equidistant

uniform dispersion

Random Dispersion

Indiv. have an unpredictable spacing pattern. Most rare dispersion pattern but happens b/c of abiotic factors influencing where an indiv. can live.

→ abiotic: wind, water, other animals

Dandelions use this type of dispersion pattern because the dandelion seeds are blown by the wind in unpredictable directions

Random dispersion example

frugivores (animals that eat fruit) randomly excrete seeds in their poop. This is an example of what?

random dispersion example

Gravity can be an abiotic factor for what type of dispersion method?

Random

→ seed and fruit dropping to the ground

Ocean currents are an example of what kind of dispersion method?

Random Dispersion

Population Demography

Study of vital statistics of a population and how they change over time

→ birth rates, death rates, patterns of survival and mortality, life span

Life table

an age specific summary of the survival patterns of a pop.

Cohort Life Table

Survivorship Cures

Geographical representation of the survivorship column of a life table

→ A plot of the numbers/proportion of individuals in a cohort still alive at each age

Plotted on a log scale allows us to focus on rates not absolute #’s of indiv. → looking at % of pop. dying

Survivorship curves

Type I survivorship Curves

• low death rates early

• survivorship drops steeply at old age

• Few offspring, high parental investment

  • e.g. large mammals (humans, elephants, whales, hippos, eagles, bears, lions)

• humans are type I

Type II survivorship curves

• Constant mortality throughout lifetime

• intermediate # of offspring, intermediate parental investment

  • e.g. rodents (6-10 offspring), songbirds, squirrels, many lizards

Type III

• High death rates early, low death rates later

• High # of offspring, low parental investment

• e.g. fish, insects, oysters, octopuses, sea turtles, trees (many seedlings).

Population Growth

change in population size over time

J-Shaped growth curve

exponential model

S-Shaped growth curve=no K

logistic model

Carrying Capacity=K

• # of individuals a species that can be supported by resources within an area. In terms of food and

N=pop. size

exponential model

What is an exponential model

• No limits to growth

• unlimited resources

• No competition → very unrealistic in nature

Protected pop. of elephants

Exponential model: Elephants saw exponential growth in the 1960s b/c they had unlimited resources and no real predators (when hunting became illegal in this area

Elephants saw expo

Ecological Succession

a predictable change in species composition of a community over time, associated with disturbance

early/ late stages =

lowest species diversity (specialists able to survive)

Intermediate stages=

highest species diversity (generalists)

Whale carcass is an example of

a complex localized ecosystem (mini)

• early stages. low diversity (hagfish & sleeper sharks)

• intermediate stages: Detected 178 diff. species on a single whale vertebrae (heterogeneity of carcass)

• 18 months later all that is left is the skeleton and bacteria & polychaete worms (low species diversity)

Ecosystem Ecology

community of organisms in an area and the physical factors (abiotic environmental factors) with which they interact → (energy flow and chemical cycling)

whats at the base of energy

• autotrophs (produce their own food using photosynthesis or chemical energy)

• Protists (green algae)

• cyanobacteria

Trophic Structure

Describes the feeding relationships of organisms in a community

Producers: Primary

• Autotrophs

• Terrestrial systems → plants

• Aquatic Systems → Phytoplankton (algae)

• Deep ocean→ chemosynthetic

Consumers

• Herbivores → eat producers

• Carnivores → eat other consumers

• Omnivores → eat producers and consumers

• Detritivores /Decomposers

Detritovores

feed on dead and decaying plant material (amphipods and millipeads)

Decomposers

break down matter making organic nutrients available to rest of ecosystem (bacteria, fungi)

food chain

linear sequence of feeding relationships that describe transfer of energy

What is each trophic level?

each step in a food chain ex. ( 1 producers)

In nature are things always linear?

NO

Food web

network of food chains that’s more realistic

Are trophic terms relative?

yes. Terms are relative depending on which “connection path” you follow

Crabeater Seals eat…

krill. they have special teeth. 2 consumers like baleen whales.

how is energy lost between trophic levels

• used in respirations → cant move on to the next trophic level

• Lost in waste (feces)

The rest of the energy that makes the transition…

Secondary production (new biomass) → used for the growth of the individual that eats the prey item

What percent of energy is lost a each trophic level?

90%

Most abundant life form on earth

Prokaryotes

bacteria are…

prokaryotes

Examples of bacteria

ocillatoria, rhizobia, bacillus

Archaea are…

prokaryotes

Prokaryotes defining characteristics

• no nucleus

• asexual reproduction (binary fission - duplicate genetic material and divides it in half)

• undergo rapid evolution

• use/have flagella

Bacteria cell walls

has peptidoglycan (rigid envelope that surrounds cytoplasm for protection from environment) in its cell wall

Archaea cell wall

No peptidoglycan in its cell wall (has an “s” (surface) layer)

What organisms grow at temperatures > 100 degrees

certain archaea species (extremophiles)

-phile means?

lover of

variation in bacteria and archaea is due to…

Mutation and horizontal gene transfer

Mutation in bacteria and archaea

permanent change in DNA sequence b/c no sexual reproduction

Horizontal gene transfer

exchanging genetic material w/ a nearby bacteria or archaea

ex. E coli can transfer material through pilus structure

Main difference between heterotrophs and autotrophs

Where their carbon source comes from

Heterotrophs

Must engulf something to gain carbon source

autotrophs

take things from environment to gain carbon source (sunlight, sulfur)

Photoautotrophs energy source & carbon source & ex

• light (from the sun),

• CO2 in some form,

• cyanobacteria, rhodobacteria (purple bacteria), phytoplankton

chemoautotrophs

use chemicals instead of light

chemoautotroph energy source, carbon source, and ex.

• inorganic chemicals (ex. H2S)

• CO2 in some form

  • Ex. nitrogen-fixing, sulfur-oxidizing, iron-oxidizing

photoheterotrophs energy source, carbon source, example

• light (from sun),

• organic compound (C6H12O6),

• ex. heliobacteria (rice fields)

Chemoheterotrophs can’t do what?

Photosynthesize (lack chlorophyll) so they must engulf or eat things

Chemoheterotrophs energy source, carbon source, ex

• Organic Compound

• Organic Compounds

• most pathogenic bacteria (E. coli, S. aureus)

Prokaryote’s critical role in chemical cycling. True?

Yes! critical role in chemical cycling

Nitrogen cycle by fixing atmospheric N2

Make it available to other organisms (plants)

Carbon cycle through decomposition and photosynthesis is what?

Key role in energy flow

how do decomposers play a role in carbon cycling?

Breakdown dead organic matter and release CO2 through cellular respiration

What do photosynthetic prokaryotes do to CO2?

Photosynthetic prokaryotes remove CO2 and fix it into sugars