Ecology

Autoecology

an approach in ecology that seeks to explain the distribution and abundance of species by studying interactions of individual organisms with their environments.

Synecology

The mass of individuals in their relationships with other communities of diff species/ populations

Metapopulation

a group of subpopulations that interact with each other through the exchange of genes

subpopulation

fraction/ subdivision of a population

Demes

a local group of individuals (same species) that interbreed with each other and share a gene pool

Autochory

when the dispersal is obtained by using the plant's own means

allochory

obtained through external means

Biotic potential "r"

max n of individuals a species can produce, max growth of the population

carrying capacity "K"

the mortality rate is \= to the natality, gain is 0

growth without regulation

in the absence of limiting factors the pop grows solely on the basis of its intrinsic growth rate

growth with regulation

the presence of limiting factors, growth is slowed down, until the pop stabilizes around the K

Lotka-Volterra equations

Mathematical equations that describe the dynamics of eco systems in which 2 species interact, 1 predator other prey

survivorship curve

Graph showing the number of survivors in different age groups for a particular species.

r-strategy

A reproductive strategy characterized by rapid reproduction of many small offspring and little or no parental care. Ex. Rabbits, bacteria.

K - strategy

A reproductive strategy characterized by long development and larger offspring that parents invest time and energy into raising

Ex. Humans, elephants.

Limiting factors

envi. factors which act on the reproductive success of indi., they influence the growth rate of a pop

Minimum Convex Polygon (MCP)

the smallest polygon in which no internal angle exceeds 180 which contains all sites

Kernel Density Estimators (KDE)

tool that calculates the density of features in a neighbourhood around those features

territory

actively defended area that can be small as a birds nest to a dog's backyard

Ecology

Scientific study of interactions among organisms and between organisms and their environment

individual

a single organism

Population

A group of individuals that belong to the same species and live in the same area

Community

All the different populations that live together in an area

Ecosystem

consists of all the organisms and the physical environment with which they interact with (biotic + abiotic)

Biom

the most extensive ecosystem on Earth classified according to the dominant vegetation and characterized by the adaptation of organisms to specific env. conditions

Biosphere

a set of all Earth's ecosystems

Biocenosis (community)

biological association of diff species living in the same territory

Biotope

fundamental unit of the env. topographically identifiable and characterized by the biocenosis that populates it

habitat

Place where an organism lives

Ecological niche

functional position of an organism in the ecosystem

Trophic chains

producers - primary consumers - secondary consumers - tetriary consumers - decomposers

Biodiversity

the variety and variability of life on Earth at all levels, from genes to ecosystems and the ecological and evolutionary processes that sustain it

Functional Richness (FRic)

the amount of functional space obtained by a species assemblage

Functional evenness

indicates how regular is the degree to which the biomass of the species assemblage is distributed in niche space to allow effective utilisation of the range of resources available

Functional divergence

represents the functional diff among species and captures the range, distribution and abundance of trait values of species in a community

Rao's quadratic entropy

measure of community - level dispersion of species in functional trait space weighted by their relative abundance

Functional trait

Any morphological, physiological, phenological or behavioural characteristic of any individual

Bioindicator

a species that is especially sensitive to ecological change and thus can serve as an indicator of environmental conditions

Flag species

species for which is easy to obtain resources for conservation

umbrella species

whose conservation requires the protection of very large areas and consequently by protecting this species many others are protected

key species

essential to maintain the existing balance in a given ecological system

Focal species

they identify an area of spatial and functional needs capable of effectively understanding all the other species in the area to be protected

taxonomic diversity

number of species in a given assemblage

functional diversity

assessing the "role" of each species present in a given assemblage

phylogenetic diversity

considering the evolutionary history of each species present in a given assemblage

Evolutionary ada

adjustment of organisms to their envi. in order to improve their chances at survival in that envi.

macroevoluion

long term, large scale evolutionary changes formation of new species etc

Microevolution

small genetic changes in a population (within species), as spread of a mutation or change in frequency of a single allele due to selection

ecological efficiency

describes the efficiency with which energy is transferred from one trophic level to the next

Opportunism

species taking advantage of opportunities or circumstances often with little regard for principles or consequences, adaptability

Idealism

promoting a nobel goal

search optimum

best conditions

Evolutionary Stable Strategy (ESS)

if it cannot be replaced or cannot be invalid by another one through natural selection

sexual selection

1. Intra - sexual: (usually males) the act of competing with members of one's own sex, as well as the evolutionary process that shapes the traits employed in this competition
2. Inter - sexual: where members of one sex (usually females) choose members of the opposite sex

General assumptions of natural selection

1. Individual variability
2. Heredity
3. High potential reproductive capability
4. Differential reproduction rate

Adaptation vs. Exaptation

a - the same function, the same selection pressures

e - describe a shift in the function of a trait during evolution process (a trait which served one function can evolve to serve another function)

Genotype

combination of alleles that such ind. possesses for a specific gene (dominant and recessive genes) inherited by parents

Phenotype

An organism's physical appearance, or visible traits influenced by genotype and other factors like env. factors

convergent evolution

Evolution toward similar characteristics in unrelated species

divergent evolution

when two or more species sharing a common ancestor become more different over time

Speciation

evolutionary process by which new species are formed from preexisting ones

ecological time (population dynamics)

interactions between organisms (hours - decades)

evolutionary time (adaptation, coevolution)

changes in genetic properties of organisms, developmental changes with populations/ species (thousand - million of years)

phyletic gradualism

speciation is slow, uniform and gradual

punctuated equilibrium

The theory that species evolve during short periods of rapid change

allopatric speciation

The formation of new species in populations that are geographically isolated from one another.

peripatric speciation

occurs when peripheral populations become geographically isolated from the main population and undergo genetic divergence and speciation

sympatric speciation

The formation of new species in populations that live in the same geographic area

species diversity

measured as the number of species and relative abundance in each community

Structure of community

describes the characteristics of eco niches, species richness of species composition with the community

Zonation (diff growth form)

horizontal layering

Stratification (diff growth form)

vertical layering

ectone

A transitional zone where ecosystems meet.

edge effect

the condition in which, at ecosystem boundaries, there is greater species diversity and biological density than there is in the heart of ecological communities.

general pattern on biodiversity

1. large habitat
2. heterogeneous landscapes
3. moderate disturbance
4. lower isolation
5. number of species tend to decrease with altitude
6. number of species tend to decrease with extreme climate conditions
7. number of species tend to decrease under human disturbance

pioneer species

First species to colonise an area created by disturbance

primary succession

An ecological succession that begins in an area where no biotic community previously existed

secondary succession

when a biocenosis is established in an env. that had already been populated but whose living beings have been eliminated by climatic modifications

Climax

indicates the more mature state of the vegetation, but the climax vegetation stabilises in a very long time

Climatic climax

when climax is controlled by the climate in the region, develops where the physical conditions are not so extreme

edaphic climax

when there're more than 1 climax com. in the region, modified by local conditions of the substrate such as soil moisture, soil nutriens...

Catastrophic climax

climax vegetation to a catastrophic event such as a wildfire

Disclimax

a relatively stable ecological community often including kinds of organisms foreign to the region and displacing the climax because of disturbance especially by humans

degrative succession

habitat degradation

autogenic succession

variations in the com determined by the internal co - actions, driven by biotic factors

allogenic succession

intervention of external forces, occupation of the habitat driven by the abiotic components of an ecosystem

system maturity

the rate between breathing an the gross prim productivity is the index of maturity of an ecological system

water cycle

continue movement of water within the Earth and atmosphere (condensation, precipitation, infiltration, runoff, evaporation)

C cycle

movement of C toms within the atmosphere: photosynthesis, decomposition, respiration, combustion

nitrification

process that converts ammonia to nitrate

Nitrogen fixation

N2 converted to ammonia, it becomes available for primary producers, plants

denitrification

Conversion of nitrates into nitrogen gas

Ammonification

decomposers convert organic waste into ammonia

O cycle

circulation of O2 in a various forms

P cycle

essential nutrient found in macromolecules of humans, other organisms and in DNA

ecosystem ecology

The study of energy flow and the cycling of chemicals among the various biotic and abiotic components in an ecosystem.

Trophic cascade

influence of the species of producers / consumers that affect at least 2 other trophic levels

top - down control

influence of predators on the relative abundance of lower trophic levels

bottom - up control

influence of predators in the relative abidance of the underlying trophic levels

global ecosystem drivers

albedo, thermohaline circulation, greenhouse effect, population change, change in economic activity, cultural factors, technological factors, sociopolitical factors