Marine Ecology Exam 2

Population

a group of individuals of same species that live in a defined area and are isolated from other populations

Life history

an organism’s lifetime pattern of growth, development, and reproduction

Parthenogenesis

asexual reproduction from unfertilized egg

Sexual hermaphrodite

organism that changes sex during its lifetime

simultaneous hermaphrodite

an organism that has both male and female organs at same time

Simple life cycle

in one environment entire life

Complex life cycle

in multiple environments entire life

Biphasic lifestyle

consist of sessile and nekton phases

r-selected species characteristics

good in unpredictible environments, and competition is lax (low)

K-selected species characteristics

good in predictable enviornments, fierce competition

Planktotrophic

larvae released from bottom dwellers, feed in inccurents, and repopulates in suitable environment

Lecithotrophic

larvae released from bottom dwellers, have internal nourishment, and repopulate in suitable environment

Direct development

mature from eggs in close proximity without finding suitable environment; look like mini adults

Wall of mouths

high amount of predators outside of reef

Carpet of mouths

high amount of benthic predators

Intrinsic aspects

biology, such as body size and life history traits

Extrinsic aspects

environment, such as habitat, resource availability, and temperature

Demography

study of size and structure of populations and spatial and temporal changes within them

Nt+1 = Nt + b + i - d - e

population change over a time period

Age structure

number or proportion of individuals of different ages

Stage structure

number or proportion of individuals of different stage classes

Dispersal

the movement of individuals in space

Emigration

individuals moving out a population

Immigration

individuals moving into a population

Passive dispersal

doesn’t choose to move

Active dispersal

chooses to move

Open population

immigration and emigration occur

Closed population

no immigration or emigration occur

dN/dt=B-D

constant population growth

dN/dt=rN

exponential growth rate

nx (Age-stage population table)

number of indivudals alive at the beggining of the age interval

lx (Age-stage population table)

number of individuals in the original cohort surviving to next age class

bx (Age-stage population table)

age specific fecundity

Ro=n(sum of)x=0 lxbx

Age stage population formula

Ro (Age-stage population table)

Net reproductive rate- average number of individuals produced by an individuals over its lifetime

Ro=1

stable population

Ro<1

declining population

Ro<1

declining population

Survivorship

proportion of individuals in a population surviving from one age group to the next

Type 1

few offspring, care for young

Type 2

constant mortality rate

Type 3

many offspring, little to no care

sx (Age-stage population table)

survivorship probablity (1-qx)

qx (Age-stage population table)

death rate

Assumptions of exponential growth model

Geographic closure, constant birth and death rate, no age structure, no time lags

K (logistic growth)

carrying capacity

r (logistic growth)

instantaneous growth rate

Intraspecific competition

competition between members of same species

a (logistic growth)

density dependant fecundity

c (logistic growth)

density dependent mortality

density dependent

any factor in a population that can change because of population density

Density dependent fecundity

decrease in fecundity with increased organisms

Density dependent mortality

increased mortality with increased organisms

dN/dt=rN(1-(N/K))

logistic growth model

Exploitation competition

competing individuals do not interact directly with each other but dominates use from competitors

Interference competition

competing individuals directly interact with each other

Interspecific competition

interactions between organisms from different species

Direct interaction

immediate relationship between two organisms where one directly affects the other

Indirect interaction

one species alters abundance or behavior of another species through an inermediate

Predator

attacks multiple life stages of prey and kills on capture

Micropredator

attacks more multiple life stages of prey but does not kill on capture

Seawater variables affecting organism physiological function

temperature, salinity, oxygen, light

Acclimation

change of function and tolerances that result from physiological conditions

Regulators

respond to environmental conditions through change

Conformers

don’t respond to environmental conditions

Homeotherms

an organism that maintains near constant body temperature

Endotherms

maintaining body temperature through internally generated metabolic heat

Poikilotherms

an organism with varying internal body temperature

Ectotherms

maintain body temperature through energy exhange with environment

Homeotherm characteristics

high metabolic rate, use of insulation, countercurrent heat exchange

Osmoregulators

maintain constant osmolarity of body fluids that differ from the enviornment

Stenohaline

tolerate narrow range of salinity

Euryhaline

tolerates wide range of salinity

Osmoconformers

internal salinity matches the environment

Low oxygen availability causes

increased ventilation, decreased heart rate, alteration of blood pigments

O2 blood pigments

Hemocyanin (Cu) Hemoglobin (Fe) Myoglobin (skelatal, cardial)

Interceullar bioluminescence

photocore cells with focus lenses and reflectors to produce light

Biochemical bioluminescence

reaction of protein with enzyme to produce light

Community

a group of species that occupy a given area, interaction directly or indirectly with each other

Community structure

species composition, or set of species present and their abundance

Processes that shape communities

Speciation, Ecological selection, Dispersal, Ecological drift

Speciation

the evolutionary origin of new species over many generations

Ecological selection

environmental tolerances and interactions among species that favor certain species under certain conditions

Dispersal

movement of organisms across sites and regions

Ecological drift

random fluxes in species abundance

Species richness

number of different species in an area

Species eveness

relative abundance of different species in an area. equitability in distrubution among different species

Species diversity

species richness and eveness combined

1 – Σ (ni/N)²

Simpson’s diversity index

Ecological niche

the role and interactions of a species in its ecosystem

Fundamental niche

full range of environmental conditions and resources an organism can possibly occupy and use

Realized niche

the part or extent of fundamental niche that an organism occupies

Vertical zonation gradients caused by

tide levels, time of air/water exposure

Horizontal zonation gradients caused by

changing wave exposures

Vertical zonation exceptions

patches instead of distinct zonation. Black lichen, periwinke, and barnacles.

Causes of vertical zonation

Physiological tolerances, larval and adult preferance, competition, predation, behavior

Meta population

a group of local populations of same species in given area linked through dispersal of potentially interacting species

Local extinction

one patch in a meta population blinks out because all individuals die

Regional extinction

whole metapopulation goes extinct because all patches blink out at same time

r=1-e

probability of local persistence.