Behavioral ecology

BIO 2500

Behavioral ecology

study of the ecological and evolutionary basis of animal behavior

proximate cause

Immediate

ultimate cause

long term, why

adaptive evolution

traits that give survival and or reproductive advantage tend to increase in frequency over time

evolution is based on_____

reproduction

advantages of sexual reproduction

-increased genetic variation

-ability to adapt in changing environments

-red queen effect

Red queen effect

reproduction to survive against other organisms (parasites/pathogens) that are constantly evolving in a changing environment

disadvantage of sexual reproduction

-only pass 50% of genetic material onto offspring

-energy expenditure

-production of males

-STDs

sexual selection

form of natural selection in which individuals with certain inherited traits are more likely to obtain mates

sexual dimorphism

males and females have secondary sexual characteristics that are different

intrasexual selection

competition within one of the sextes (mTm or fTf)

ornamates

help a male attract females

armaments

help male to combat other males

Intersexual selection can lead to___,___,___

extreme variance in reproductive success

Males may compete for territory

Alternative mating strategies

intersexual selection 

female mate choice

Mating system types

promiscuous

Monogamy

Polygamous

polygyny

one male mates with many females

Anisogamy

two different sized gametes results in differential investment in reproduction

females are___ and males are ____

choosey, cheap

Certainty of paternity influences parental care and mating behavior because

The more certain the male is that the offspring are his, the more likely he is to care for them

Operational sex ratio

Ratio of female to male capable of reproducing at a certain time

Benefits of living in a group

• higher reproductive success

• Group may share feeding and care of young (kin selection)

• Reduced risk of predation (dilution effect)

Dilution effect

as the number of individuals in a group increases, the chance of being the one attacked by a predator decreases

Costs of group living

• Larger the group is, the larger the competition for food is and the faster resources decrease

• More time may be spent moving btwn feeding sites

• Completion for food can be more intense

• In a group with a hierarchy, subordinate members can spend more time and energy interacting with group members

• Diseases can spread more easily

Distribution

Geographic area over which individuals of a species occur

Abundance

The number of individuals in a specific area

population

A group of individuals of the same species that live within a particular area and interact with one another

How plants disperse

seed movement

Actual distribution

the combination of biotic and abiotic features

disturbance events

hurricanes

Floods

Drought

Fire

disturbance

Events that kill/damage some individuals creating opportunities for other individuals to grow and reproduce

geographic range includes_____ in which species occupy during _____ life stages

areas,all

dispersion

spacial arrangement of individuals within a pop

regular/uniform dispersion

individuals are evenly spaced

Random dispersion

Individuals scatter randomly (least common)

Clumped dispersion

individuals are grouped together (most common)

absolute population size has the _____ number of individuals

actual

relitive population size has the _____ number of individuals

estimated

Area based count types

complete (total)

Incomplete count

Indirect count

Mark-recapture method

used to mark mobile organisms, they are tagged, marked, released, recollect, analyse and count the captured that have never been marked

ecological niche

the biological conditions that a species needs to grow, survive, and reproduce

A niche model is a ___________ used for ___________

Predictive tool, modeling known environmental conditions occupied by that species

Equation to find density

D= n/a

Four factors that impact growth in population size

birth death immigration emmigration

what does the constant K stand for

K-selection, carrying capacity

Population cycles

a boom and bust cycle where there are periods of high and low abundance at regular intervals

What type of graph is a representing

logistical growth

What type of graph is C representing?

Population cycles

delayed density dependance

the current population is based on/ dependent on a past population size

stochasticity

random events that can effect a population

demographic stochasticity

average population level birth and death rates are constant in a given year, but the actual fates of individuals are differed on random events

metapopulations- are defined by constant _____, and _______. And occurs in spatially ______ populations linked by ____ ____

extinction, colonization. isolated, gene flow

Populations of some species are prone to extinction for two reasons

1- landscapes are patchy, so dispersion is difficult

2- env. Conditions change rapidly and undredictibly

habitat fragmentation

Large tracts of habitat are converted to spastically isolated fragments, resulting in metapopulation structures

Life table

a summary of how survival and reproductive rates vary with age.

cohort life table

follows the fate of individuals all born at the same time

static life table

survival and reproduction of individuals of different ages during a single time period

cohort life tables are used on ______ organisms

sessile 

static life tables are used on _______ organisms

static

survivorship curve

what survivorship and mortality looks like over time

type 1 survivorship curve

most individuals survive to old age

-parental care, few large offspring, large sizes

Associated with K-selection

type 2 survivorship curve

The chance of surviving remains constant through lifetime

Type 3 survivorship curve

high mortality rate for young

-many small offspring

R-selection

survivorship curves can vary ____, ______, _______

among species, between males and females, among cohorts

age structure

proportion of the population in different age classes

Exploitation

a relationship where one organism benefits by feeding on and therefore directly harming another organism

herbivore

eats tissue or internal fluids of living plants or algae

predator

kills and eats other organism(prey)

parasite

lives in or on another organism(host), feeding on parts of it (doesn’t always kill host)

Types of parasites that cause diesease

pathogens

four prey adaptions to avoid being eaten 

-camouflage

-startle

-warn (colors)

-disrupt

Three prey adaptations to prevent capture

-camouflage

-startle

-warn

one type of adaptation to escape capture

disrupt

4 Prey adaptations in social species

vigilance

Decrease foraging in open areas

Use sentinels

Alarm calls

4 Adaptations in predators

distendible jaws and recurved teeth

Venom

Mimicry

Detoxing/tolerating prey defense chemicals

hemotoxin

attacks blood

Hemmorrhagic toxin

causes internal bleeding

cytotoxin

attacks and melts Tissues

neurotoxin

Attacks nerves (stiff paralysis)

myotoxin

attacks muscles (limp paralysis)

3 Adaptions in herbivory 

-toxic secondary compounds (deters herbivory directly)

-Compounds that attract the parasitoids and predators of the herbivores 

-compensation

Compensation

Compensating for loss of biomass, investment in lateral growth

Only notable in early growing season, as it mainly for reproduction