Download - Science 9 Unit A – Biological Diversity 1.0 – Biological Diversity and the Variety of Life on Earth
Science 9 Unit A – Science 9 Unit A – Biological DiversityBiological Diversity
1.0 – Biological Diversity and 1.0 – Biological Diversity and the Variety of Life on Earththe Variety of Life on Earth
Goals of this Section:Goals of this Section:1.1. Describe the abundance of species on Describe the abundance of species on
Earth and in different environments.Earth and in different environments.2.2. Explain the role that variation plays in Explain the role that variation plays in
survival.survival.3.3. Identify examples of niches and how Identify examples of niches and how
closely related living things can closely related living things can survive in an ecosystem.survive in an ecosystem.
4.4. Explain how the survival of one Explain how the survival of one species depends on other species.species depends on other species.
5.5. Identify examples of natural selectionIdentify examples of natural selection
1.1 – Examining Diversity1.1 – Examining Diversity
Biological Diversity: All of the Biological Diversity: All of the different types of organisms on Earthdifferent types of organisms on Earth
Scientists, of course, rarely study all Scientists, of course, rarely study all of the Earth’s creatures togetherof the Earth’s creatures together
Rather, they focus on smaller Rather, they focus on smaller groupingsgroupings
Divisions in EcosystemsDivisions in Ecosystems
DiversityDiversity
Each ecosystem is differentEach ecosystem is different This is because they contain different This is because they contain different
biotic and abiotic componentsbiotic and abiotic components These components dictate which These components dictate which
organisms can be found living in a organisms can be found living in a particular ecosystemparticular ecosystem
Genetic VariationGenetic Variation
This term refers to the variation This term refers to the variation between individuals of the same between individuals of the same speciesspecies
These variations are typically due to These variations are typically due to small differences at the cellular levelsmall differences at the cellular level
Some of these variations may not Some of these variations may not even be visibleeven be visible
DistributionDistribution
Species are not Species are not evenly distributedevenly distributed
Regions near the Regions near the equator typically equator typically have a far greater have a far greater number of species number of species than those regions than those regions near to the polesnear to the poles
ClassificationClassification
Carolus Linnaeus developed a Carolus Linnaeus developed a system for naming and classifying system for naming and classifying organisms in the 18organisms in the 18thth century century
The purpose of this system was to The purpose of this system was to establish common scientific names establish common scientific names rather than using names that varied rather than using names that varied from language to languagefrom language to language
Binomial NomenclatureBinomial Nomenclature
Under the Linnean system, all Under the Linnean system, all organisms have two names – their organisms have two names – their genus and their speciesgenus and their species
For example, a wolf is known as For example, a wolf is known as Canis lupus Canis lupus
CanisCanis represents the genus and represents the genus and lupuslupus identifies the species identifies the species
The Five-Kingdom The Five-Kingdom Classification SystemClassification System
KingdoKingdomm
PlantaePlantae AnimaliaAnimalia
PhylumPhylum coniferophytconiferophytaa
ChordataChordata
ClassClass pinopsidapinopsida OsteichthyesOsteichthyes
OrderOrder pinalespinales SalmoniformSalmoniformeses
FamilyFamily pinaceaepinaceae SalmonidaeSalmonidae
GenusGenus PiceaPicea SalvelinusSalvelinus
SpeciesSpecies glaucaglauca confluentusconfluentus
White spruce
BullTrout
Diversity Under the SeaDiversity Under the Sea
Some regions, such as coral reefs Some regions, such as coral reefs have very high levels of biodiversityhave very high levels of biodiversity
The coral itself is a living thing, and it The coral itself is a living thing, and it also houses thousands of different also houses thousands of different species of life species of life
1.2 - Interdependence1.2 - Interdependence
No one species lives aloneNo one species lives alone All species are reliant on other All species are reliant on other
species for some aspect of their daily species for some aspect of their daily lives lives
Food chains and food webs show the Food chains and food webs show the relationship between predator and relationship between predator and prey prey
Even prey Even prey benefit from benefit from the predator-the predator-prey prey relationshiprelationship
SymbiosisSymbiosis
Sym-togetherSym-together Bios-lifeBios-life This is the association between two This is the association between two
different species that live close different species that live close togethertogether
There are different types of symbiosis There are different types of symbiosis depending on the benefit or harm to depending on the benefit or harm to each participant each participant
CommensalismCommensalism
one benefits the other is neither one benefits the other is neither harmed nor helped harmed nor helped
MutualismMutualism
both are benefited both are benefited
ParasitismParasitism
one benefits and the other is harmed one benefits and the other is harmed
NichesNiches
The role of an organism within an The role of an organism within an ecosystem ecosystem
Interspecies competition occurs Interspecies competition occurs when two different species are when two different species are competing for the same nichecompeting for the same niche
Resource PartitioningResource Partitioning
For similar species to coexist in an For similar species to coexist in an area, they must share resourcesarea, they must share resources
This can be accomplished by each This can be accomplished by each species changing their niche slightly, species changing their niche slightly, so there is no direct competitionso there is no direct competition
This figure This figure shows resource shows resource partitioning partitioning between three between three warbler species warbler species in a single treein a single tree
1.3 – Variation Within 1.3 – Variation Within SpeciesSpecies
Just as there is variation between Just as there is variation between species, there is variation within species, there is variation within species as wellspecies as well
Variation within a species is known Variation within a species is known as variabilityas variability
Variability and SurvivalVariability and Survival
Sometimes environments changeSometimes environments change In these cases, variability in a In these cases, variability in a
species will increase the chance of species will increase the chance of some of the individuals surviving that some of the individuals surviving that changechange
Antibiotic ResistanceAntibiotic Resistance Some bacteria are Some bacteria are
naturally resistant naturally resistant to antibioticsto antibiotics
When a bacterial When a bacterial population comes population comes into contact with into contact with these drugs, the these drugs, the naturally resistant naturally resistant ones will survive ones will survive and reproduceand reproduce
Natural SelectionNatural Selection
Natural selection occurs when the Natural selection occurs when the environment “selects” which environment “selects” which individuals survive long enough to individuals survive long enough to reproducereproduce
The survivors usually have adaptations The survivors usually have adaptations that make them more suited to the that make them more suited to the environment, and the adaptations are environment, and the adaptations are passed on to their offspringpassed on to their offspring