Flashcards
EcologyMidterm
Cards in this deck (156)
- 1The term Ecology was first introduced by?Ernst Haecke
- 2Ecology is defined asa study
which deals with inter-relationship
between living organisms and their
environment - 3Ecology is scientific study that incorporates ahypothetical/deductive
approach - 4Ecologists recognize a hierarchy of organization in the environment:Biosphere
Ecosystem
Community
Population
Organism - 5Consists of all Life on Earth and all parts of the Earth in which life exists, including land, water and the atmosphereBiosphere
- 6The Biosphere is comprised of smaller units calledEcosystems
- 7all the interacting organisms living in an areaCommunity
- 8When the focus is on interactions of groups of different organisms, or species that is called the?Population
- 9any member of a single species is called a?Organism
- 10group of individual organisms that are capable of interbreeding to produce fertile offspring in natureSpecies
- 11Approximately how many species are there on earth?8.7 Million
~75% animals
~4% are vertabrates
~48% fish - 12the identification, naming and classification of speciesTaxonomy
- 137 Levels* of Taxonomic ClassificationKingdom
Phylum
Class
Order
Family
Genus
Species - 14FIVE KingdomsPlantae,
Animalia,
Monera (Bacteria),
Protista (Single-celled)
Mycota (Fungi) - 15reflects/indicates evolutionary interrelatednessphylogenetic
(ie the classification system is phylogentic) - 16Every ecosystem is composed of two types of “stuff”Biotic and Abiotic Factors
- 17Factors relating to life and living organisms, or caused by living organisms (living factors)Biotic Factors
- 18components of an ecosystem not containing or supporting life (non-living factors)Abiotic factors
- 19The recycling of materials through use of food sources is called aFood Chain
- 20three basic groups within every food chainAutotrophs
Heterotrophs
Decomposers = Saprotrophs & Detritivores - 21A food chaindetermines the flow
of energy and nutrients from one
organism to another through an
ecosystem - 22_______ reflect the position an organism occupies in the food chain – Producer vs Consumer vs DecomposerTrophic Levels
- 23heterotrophs includeAnimals, bacteria, fungi
- 24live on or in dead material, secreting digestive enzymes and absorbing nutrientsSaprotrophs
(“rotten nourishment”) - 25ingest dead organic material and internally absorb nutrientsdetritivores
(detritus eating) - 26heterotroph level can be divided intoPrimary, Secondary and
Tertiary/Apex consumers - 27Primary Consumers (herbivores) obtain energy byconsuming various
producers - 28Secondary Consumers obtain energy byconsuming primary producers
sometimes plants as well - 29Tertiary Consumers (top carnivores) obtain their energy byeating primary
and secondary consumers, and in
some cases plants as well
(Are often key stone species) - 30Multiple food chains put together form a?Food web
(the basis for calculating biodiversity) - 31Food webs...?Are comprised of 2 or more food chains
&
Show ALL interconnections between ALL
species, regardless of trophic level - 32When were wolves reintroduced to Yellowstone?1995
- 33What is a trophic cascade?Altering any trophic level in terms of
it’s species composition can have small
or large scale impacts on other trophic
levels and species - 34Predationany interaction between
two organisms in which one
organism (the predator) kills and
consumes all or part of another
organism (the prey) - 35Predation usually results in the evolution ofDefensive Adaptations
(Chemical, Behavioural, Morphological) - 36MIMICRYlooking like an
organism with a
heightened defense
system
(ie: viceroy butterfly) - 37Seasonal Coat Colour Moultingspecies that change colour completely
depending on the season - 38Predator AdaptationsChemical Offense
Behavioural Adaptations
Morphological Changes
(Camouflage, Speed, Specialized Features) - 39Co-evolutionwhen two species evolve in response to each other
(ie: predators evolve better hunting strategies in response to prey defences. Prey evolve better avoidance strategies
in response to predation) - 40Competitionan interaction between
organisms that require the same
limited resources
(intra or interspecific) - 41Intraspecific Competitionbetween members of the same species
Determines which individuals of a species survive - 42Interspecific CompetitionBetween two or more different species
important tool in limiting the total size of
various populations - 43resource partitioningArises from interspecies competition
species specializes on a slightly different
resource, or they alter activity times for
exploiting the resource (nocturnal vs
diurnal) - 44character displacementDue to exact same resource competition
a species can evolve to alter their
niche - 45Symbiotic relationshipsbetween two or more totally different
species where at least one species
depends upon the relationship to
survive - 46Symbiotic Relationships: MutualismBoth partners benefit from
the relationship (+,+) or win-win - 47Symbiotic Relationships: Commensalismone partner benefits
from the relationship; the other partner is
not affected (+,0) or win-draw - 48Symbiotic Relationships: Parasitismone partner benefits from
the relationship; the other partner is
harmed (+,-) or win-lose - 49Symbiotic Relationships: Amensalism(-, 0), or lose-draw, is also
listed in some sources, but is very difficult
to prove unequivocally! - 50Population Ecologystudies the
dynamics of why populations of
species increase or decrease over
time - 51Reproduction does not help an individual to surviveit helps a species to survive by
replacing the aging population - 52Asexual reproductionAll offspring are exact genetic copies
of their single parent
(Rare in vertebrates) - 53Parthenogenic births result inFewer offspring than typical
- 54gonochoristicthat is,
they mature with either male or female
gonads/reproductive organs - 55Sexual ReproductionAll offspring are a combination of
gamete cells from two different parents
- 97% of all species use this method - 56Sexual reproduction ProsGreater genetic diversity = greater
adaptability, better chance of survival
Males are free to care for females and young
Potential for passing on better genes
through natural - 57Sexual Reproduction ConsFemales must compensate for males
lack of reproduction by producing twice as many offspring
Chance of genetic error
Mating rituals potentially harmful (time-consuming courtship, disease transmission, injury from competition amongst males) - 58Amniotic embryosdevelop from eggs that
are protected by a membrane (the
amnion), and nourished/cleansed through
additional structures (e.g. umbilical cord)
(Birds, Reptiles, Mammals) - 59Anamniotic eggsdo not have an
embryonic membrane, and are not
nourished or protected by additional
structures or by the parent through a
direct connection; these eggs also cannot
be laid on land
(Fish, Amphibians) - 60viviparousSpecies that give birth to live young
(Most mammals, some snakes, very few fish) - 61placentalsPlacental offspring develop from an
amniotic egg/embryo connected to the
placenta
They have gestation
periods of varying length, depending on
the species, and give birth to live young - 62precocialready to
go as soon as they hit the ground, or they
can be - 63altricialhelpless and requiring
intensive care by parents - 64oviparousegg-layer
- 65adelphophagyYoung are born internal to the mother
(as live-bearers), but instead of getting
all of their nutrients for growth from
their mother, they get them from their
siblings - by cannibalism - 66Ovoviviparousprolonged egg retention
they retain fertilized eggs inside their bodies and then give birth to live young
(30% of snakes - Vipers, Boas, Anaconda, Garter snakes
Guppies, hammerheads, bull sharks) - 67Ovuliparouseggs are fertilized externally by the male after the female lays them
(FIsh, common in frogs) - 68sequential hermaphroditesthey start out one
gender, then switch later in life
(not common in mammals but some fish) - 69ProtandrousHermaphrodites that switch from male to female
(Clown fish, Baramudi) - 70ProtogynousHermaphrodites that switch from Female to Male
- 71Monotremesfive vertebrate mammals lay eggs
instead of giving birth to live young
(Duck-billed Platypus and 4 species
of Echidna)
(have 10 sex chromosomes) - 72Marsupialspouched mammals
birth live young, but at a very reduced gestation time, so young emerge essentially at the embryo stage They then crawl up the mother’s belly and into her pouch, where they nurse, and remain until they are fully developed - 73Reproduction selection patternsr-selected or k- selected
- 74R-selected speciesOpportunists
Young reproductive age
Short generation times
Give little or no parental care
Short lifespan
Opportunistic - invade new areas
Population not regulated by density
(boom and bust cycles)
Examples: Rodents, fish, insects, crops - 75K-selected speciesCompetitors
Produce later in life
Have few offspring
Have long generation times
Put energy into nurturing and protecting
offspring
Mature slowly, have longer natural lives
Have low infant mortality rates
Maintain numbers in stable ecosystems
Population stabilizes near carrying capacity
Examples: most large mammals, birds of prey,large/long lived plants - 76Survivorship curvesrepresent the age structure within a particular population
Some reproduce early and have
short life curves
Others reproduce later in life and
have longer life curves - 77Survivorship Curves 3 typesLate Loss Curves
Early Loss Curves
Constant Loss Curves - 78Late loss curves (k-selected species)Most death occurs at older age (e.g. large
mammals) - 79Early loss curves (r-selected species)many offspring
high juvenile mortality
high survivorship once young reach adulthood - 80Constant loss curvesIntermediate reproductive patterns
Constant rate of mortality, steady declining
survivorship curve (examples: lizards,
songbirds, smaller mammals, etc.) - 81Carrying capacityThe
number of organisms that can
sustainably be supported in a given
area indefinitely - 82limiting or regulating factorsEnvironmental factors that keep
population sizes in balance with the
carrying capacity - 83Regulating Factors includeFood availability
Space
Oxygen content (aquatic ecosystems)
Nutrient levels in soil profiles
Amount of sunlight
Territory availability
Age - 84Biotic potential of a populationAny variation in the ability of a
population to grow - 85Environmental resistance consists ofall the regulating factors acting
jointly to limit the growth of that
population - 86Carrying capacity is determined bybiotic potential &
environmental resistance - 87Populations increase through? and Decreases through?+ birth and immigration
- death and emmigration - 88Limiting Factors includeHigh percentage of old (post-
reproductive) organisms - 89Intrinsic rate of increaserate at which a population would
grow if it had unlimited resources - 904 Types of populationsStable: Fluctuates slightly above
and below carrying capacity
Irruptive: Populations explode and
then crash to a more stable level
Cyclic: Populations fluctuate and
regular cyclic or boom-and-bust cycles
Irregular: Erratic changes possibly
due to chaos or drastic change - 91BiodiversityIs a term used to describe the variety of life
on Earth. It refers to the wide variety of
living organisms and ecosystems that
exist within the biosphere - 92At which level is biodiversity most commonly studied?Species
(Due to simplicity) - 93Genetic variationis a key factor in
determining the ability of individual
organisms and species to adapt to
changes in their environment - 94Ecosystem biodiversity deals withspecies distribution in a larger area,
and with the role of key species - 95Alpha diversityis within habitat diversity
- 96Beta Diversityis between-habitat
diversity. This refers to changes in
diversity along an environmental
gradient - 97Gamma Diversityor large-scale
landscape diversity combines alpha
diversity and beta diversity - 98Species Richnessthe number of
different species found in a specific area,
or biomass per species, or even the
number of communities in an ecosystem
More species = more rich - 99Species Evenness measuresthe abundance or
distribution of individuals of each
species present within an area –
useful for vegetation, since it is
stationary - 100Measuring taxonomic differenceConsiders not just the
richness of species but how closely
related they are. Many closely related
species would still be less diverse than
fewer distantly related species - 101Species richness or evenness can be measured across various areas – but often ecologists need to account for spatial differences due tohabitat differences
(ie: a single stretch of river,
the species richness and evenness in
riffle areas will always be different than
that in pool areas) - 102BiomesAre global in nature
large distinct zones created when studying biodiversity on an ecosystem level - 103Biomes are definedgeneral characteristics of the regional
climate and the limitations or requirements imposed on species by specific temperatures and/or precipitation patterns
Substrate type often a factor - 104latitudinal biodiversity gradientTropical areas generally have more plant
and animal biodiversity than high
latitudes, measured in species richness - 105Altitudinal Gradientspecies are spread across the
planet based on Altitude as well The temperatures and moisture levels
typical of various altitudes have
historically limited vegetation types
along elevation lines - 106Name 4 BiomesTundra
Taiga/ Boreal Forest
Temperate Rainforest
Deserts
Temperate grasslands: prairies
Temperate Deciduous forests - 107Aquatic biomes (marine and fresh water) cover three-quarters of the Earth's surface:Rivers and lakes
Wetlands
Coral reefs
Estuaries
Open ocean - 108Aquatic biomes can change...daily or seasonally
(tides, freeze, dry) - 109freshwater biomes temperature can fluctuate between?-40 - +40ºC
- 110Factors Affecting BiodiversityWater
Sunlight
Seasons - 111Evolutionary ecologythe intersection of
ecology and evolutionary biology - 112define a theoryA theory summarizes a hypothesis that has been supported by repeated testing
valid as long as there is no evidence to dispute it, but technically
theories can be disproved - 113When and who offered the first theory of evolution?Lamarck in 1801
- 114What as Lamarcks theory?that organs that got used more than
they had in the past would continue to grow over
generations, while other unused organs would
shrink - 115Vestigial” organsorgans or structures
remaining or surviving in a degenerate,
atrophied or imperfect condition or form” - 116Wallace and Darwin released their findings when?1858 at the Linnean Society
- 117Darwin's finches showed adaptation through...natural selection and
common ancestry - 118Biological evolutionDescent
with modification - 119central idea of biological evolution is thatall life on Earth shares common ancestors
- 120phylogeny or a “phylogenetic treeevolutionary relationships and
represent them on a "family tree
(is a hypothesis about relationships between species) - 1213 phylogenetic domains1. Bacteria
2. Archaea
3. Eukarya - 1226 KingdomsArchaebacteria, Eubacteria,
Plantae, Fungi, Protista and Animalia - 123Post Orbital Fenestraeopenings in the
skull, behind the eye socket, that allow
muscles to attach and stretch
(used to distinguish mammals, birds and reptiles) - 124Sauropsidsincludes all living and extinct birds and reptiles
further divided into Anapsids (no fenestrae) and Diapsids “two arches” (2 fenestrae)
anapsids are largely extinct - 125Synapsids“fused arch” – single fenestrae –
includes all living and extinct mammals - 126Homologous charactersCharacteristics
in different organisms that are similar
because they were inherited from a
common ancestor that also had those
characteristics - 127examples of homologous charactersfour limbs of tetrapods
Birds, bats, mice, and crocodiles all
have four limbs; Sharks and bony fish
do not
presence of 4 limbs = homology - 128Analogous Charactersseparate
evolutionary origins,
but are superficially
similar
(ie: bird and bat wings) - 129convergent evolutionunrelated
organisms evolve similar body forms,
organs, colour, etc. because they
adapt to similar environments or
ecological niches - 130Parallel evolutionIf a similar trait evolves in two descendants
who are from related ancestors, it is
considered parallel
( similar to convergent,
and the two are often confused) - 131divergent evolutionwhereby similar
organisms evolve completely different traits, becoming increasingly distinct (they
“diverge”) - 132Molecular clocksallow scientists to use the
amount of genetic divergence between
organisms to extrapolate backwards to
estimate dates - 133Evolution ishe process by which modern
organisms have descended from ancient
ancestors - 134Fundamental to the process of evolution aregenetic variation and heritability
Genetic differences that are heritable and
passed on to the next generation can be
modified - 135Evolution only occurs whenthere is a
change in gene frequency within a
population over time
*Change over time* - 136Who and when discovered that a gene is an “all or nothing” entityMendel (1865)
- 137Gene PoolsAll of the genes in a single population of
one species are referred to as a “gene
pool” – human, lion, etc.
The mix of genes in each “pool” is what
distinguishes each species - 138hybridizationWhen two species are VERY closely
related, so that their gene pools are
almost identical, they may be able to
breed to produce offspring (either
fertile or not) - 139genetic driftone specific gene to increase or
decrease in frequency. - 140how does a selective shift in genes occur within a species or population?Artificial Selection
Genetic Processes
--ie: Genetic Mutation
Natural Selection - 141genotypethe combination
of all of your genes that make up
your DNA (whether expressed or not) - 142phenotypeis all of your
observable characteristics, which
are influenced by your genotype
and by the environment - 143alleleIndividual copy of a gene pair
(Dominant or recessive) - 144examples of dominant and recessive allelesDom= brown eyes, dimples
Rec= blue eyes, Taste of cilantro, asparagus or broccoli - 145Artificial Selectionmodification of a
species by human intervention to
ensure that desirable traits are
represented in successive generations - 146Differences in genotype can cause changes in phenotypeie: russian fox experiments
- 147Flowers are often selected based on their colourInsects have colour vision – but to them
the whole spectrum shifts towards
ultraviolet, away from red. They see
yellow, green, blue and violet, plus UV - 148red flowers are pollinated by?birds
bees cannot really see them at all - 149sexual selelctiontyp fancy characteristics intended to attract a mate
- 150Positive selectiontraits developed to create a positive response (ie: attract a mate)
- 151Negative selectiontraits developed to create a negative response (Ie: bright colours to advertise poison)
- 152A mutation in a gene isa permanent change in the
DNA sequence that makes up a gene.
They can affect a single cell or large parts
of the chromosome - 153Penicilin was discovered? Developed? resistance?1928
1940
1946 - 154Lenski's bacteria experiment has been going on for?34 years
- 155plasticityChanges have also been observed to
occur within a SINGLE generation
(ie: Commodore Butterflies
change colour depending on whether it
is a dry or wet season) - 156Where two populations of the same species become isolated by some factor – plate tectonics, a new river, even something like a forest being cut down in between them, they may become genetically isolatedSeparation isn’t the only factor –
selection has to occur in each separate
population to make them diverge. Gray
wolves in Russia are still similar enough
genetically to Gray Wolves in North
America that they could reproduce if they
could reach each other
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- Environmental Studies Flashcards on EcologyMidterm, created by Kian Robson on 01/03/2023.
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