2 Biodiversity and evolution Evolution has generated a very wide variety of organisms.The fact that all organisms share a common ancestry allows them to be classified.There is increasing recognition of the need to maintain biodiversity.
3 BiodiversityBiodiversity is an important indicator in the study of habitats.
4 ClassificationClassification is an attempt to impose a hierarchy on the complex and dynamic variety of life on Earth.Classification systems have changed and will continue to change as our knowledge of the biology of organisms develops.
5 Evolution“Nothing in biology makes sense except in the light of evolution”Theodosius Dobzhansky, 1973.
6 Maintaining Biodiversity Maintaining biodiversity is important for many reasons.Actions to maintain biodiversity must be taken at local, national and global levels.
8 Learning Outcomesdefine the terms ‘species’, ‘habitat’ and ‘biodiversity’explain how biodiversity may be considered at different levels;habitat,speciesgenetic
9 Biodiversity The biodiversity of an area is a measure of: Different ecosystemsNumber of speciesNumber of individuals of each species
10 Biodiversity “structural and functional variety in the living world” Levels of biodiversityRange of habitats in which different species liveThe differences between speciesGenetic variation between individuals of the same species
11 Species - definition Species “a group of organisms, with similar morphological, physiological, biochemical and behavioural features, which can interbreed to produce fertile offspring, and are reproductively isolated from other species”This often leads to disagreements and uncertainties when classifying or identifying species
12 Species – the two groups of criteria Group of organismsCapable of interbreedingCapable of producing fertile offspringReproductively isolated from other groups“biospecies”Group of organisms showing similarities in characteristicsMorphologicalPhysiologicalbiochemicalEcologicalbehavioural
13 Habitat – definitionA habitat is the place where individuals in a species live.Organisms show adaptations to their habitatA full description of the habitat includes the physical and biological factors that characterise that environment
14 Examples of habitats Name of the place A description of dominant vegetationConiferous forestOak woodlandTropical rainforestGrasslandA type of environmentFreshwater pondRock pool on a rocky shore
15 The State of the planetDavid Attenborough presents a series of three programmes looking at the “state of the planet” to address the concern below.One species (humans) can so alter its environment that it can destroy whole species, and indeed whole environments.How great is the damaged that is being caused?Why is it that what we do is so destructive?What can we do to change?
16 The state of the planet Programme No. 1 The Biodiversity on EarthIn order to understand the impact that humans are having on the environment we first need to understand the variety of life on the planet, the biodiversity.Watch the DVD and answer the questions on the worksheet.After watching the DVD write out your thoughts on the statementWhy conserve ecosystems?
18 Measuring Biodiversity learning Outcomes explain the importance of sampling in measuring the biodiversity of a habitat describe how random samples can be taken when measuring biodiversity
19 Measuring biodiversity To measure biodiversity you need to find outWhat species are presentThe abundance of each speciesThe distribution of each species across the areaCompile a species listIdentification keysObservationTrapping of mobile animals
20 Measuring biodiversity DistributionWhere the species is foundAbundanceHow many of each species are presentEstimating abundanceTake a representative sampleMultiply up
21 Random sampling Study a small part of the habitat Sample sites must be selected at randomTake samples at regular intervalsUse random number tablesSelect co-ordinates from a map
22 Number of samples The number of samples taken will depend on The size of the habitatThe time of yearThe diversity of the habitat being studied
23 Recording results Prepare a table Space for all species Space to record the data for each sample site
24 Sampling techniques Quadrats Transects Choose a suitable quadrat size Place quadrat at randomIdentify plantsMeasure their abundanceTransectsPut a tape measure across the habitatRecord all species touching the lineCan record at intervals
25 Sampling techniques Belt transect Interrupted belt transect Continuous belt transectUsed to survey rocky shores or sand dunesInterrupted belt transectcontinuous belt transect
26 Measuring abundance Percentage Cover Abundance scale – subjective Proportion of quadrat’s area occupied by the speciesGrids can help with estimatesUse a point frame within a quadratInclude bare groundAbundance scale – subjectiveACFOR scalesAbundantCommonFrequentOccasionalRareSpecies frequencyProportion of quadrats with the species present
27 Rocky Shores Some text, photos and diagrams taken from: Marine Field Course Guide to Rocky Shores (1992) by S.J. Hawkins & H. D. Jones
28 Learning OutcomesTo understand that zonation occurs on a rocky shore, and the factors that control this distributionTo identify a range of organisms living on a rocky shoreTo understand the importance of carrying out biological surveysTo carry out a “paper-based” transect looking at the distribution of organisms on a rocky shoreTo present results as a kite diagram, and write a report of their findings.
29 Rocky Shore Ecology The seashore is the boundary between land and sea. A sharp change in environmental conditions occurs between the low tide mark and the splash zone.Most shore plants and animals have evolved from marine ancestors.
30 ZonationBiomass, biodiversity and community complexity increases towards the lower shore as conditions are better for marine organisms; competition for space and food is intense.Species occur in distinct communities or horizontal bands on the shore known as zonation.
31 Splash zoneAs you can see from these diagrams organisms show zonation.You can also see that the organisms present varies according to the exposure of the shore.Low tide
32 ActivityFor each zone write in the degree of stress for each abiotic and biotic factorAdd on two arrows to show the direction of increasing stress caused by abiotic (red) and biotic (green) factors on the rocky shore
33 Factors affecting the distribution of organisms Survival is most difficult near the top of the shore.Biomass and biodiversity of animals and plants is low.Those plants and animals that can survive have little competition e.g. for space, and may be abundant.
34 Rocky Shore TransectOn the A4 “rocky shore” draw a belt transect using 3cm2 quadrats.Calculate the abundance of each species of “plant” and “animal” in each quadrat, record your results in the table provided.Write a report on the distribution of organisms on the rocky shoreExtension ActivityPresent your results as a kite diagram for five seaweeds and five animals.
35 Sampling in School Grounds Suggested activitiesTransect in grass outside chapelRandom quadrat sampling of two sitesOptimum quadrat size for pinkie fieldsOptimum quadrat numberSpecies frequency on pinkie fieldsComparison of percentage cover and ACFORAll students quantify the same 10 quadrats and allow for comparison
36 Sampling Animals If the animals are mobile Catching animals ObservationObservation of signs left behindOwl pellets, droppings, burrows etcCatch or trap animals and estimate numbers from the trapped sampleCatching animalsSweep nettingKick samplingTree samplingPitfall trapTulgren funnelLight trap
37 Surveying school grounds Suitable methods that could be used in school includeSweep netting in the long grassTree samplingPitfall trapTulgren funnelTo allow for a comparison, each sample should be done at two sites, and some abiotic readings should be taken.
38 Summary of the impact of sampling Sampling may cause damage to a habitatTemporary disturbanceLong term disturbanceExampleTramplingDigging for pitfall traps etc
39 Why do we need to study habitats? Assess human impactEIA – Planning processTo highlight the importance of maintaining habitats and reducing the damage
40 Learning Outcomesdescribe how to measure species richness and species evenness in a habitatUse Simpson's Index of diversity (D) to calculate the biodiversity of a habitat using the formula D = 1 – (∑(n/N)2)Outline the significance of both high and low values of Simpson’s Index of Diversity (D)
41 Measuring Biodiversity Species richnessNumber of species present in the study areaSpecies evennessMeasure the abundance of individuals in each speciesIncreasing species richness and species evenness will increase biodiversity
42 Simpson’s diversity Index Measure of biodiversity taking into account species richness and species evennessFormulaD = 1 – [∑(n/N)2]n = number of individuals of a particular speciesN = total number of all individuals of all species
43 Progress QuestionUse Simpson’s index to calculate the diversity of a habitat that contains the following organisms20 woodlice5 mice1 shrew32 earthworms15 grasshoppers1 owlComment on the diversity of this habitat
45 Answers to progress questions D = 1 – 0.306D = 0.694
46 Module 3: Biodiversity and evolution 2.3.2 ClassificationModule 3: Biodiversity and evolution
47 ClassificationClassification is an attempt to impose a hierarchy on the complex and dynamic variety of life on Earth.Classification systems have changed and will continue to change as our knowledge of the biology of organisms develops.
48 Learning OutcomesDefine the terms classification, phylogeny and taxonomy.Explain the relationship between classification and phylogeny.Describe the classification of species into the taxonomic hierarchy of domain, kingdom, phylum, class, order, family, genus and species.
49 Definitions Classification Phylogeny Taxonomy Taxon The grouping of organisms into categories based on various featuresPhylogenyStudy of evolutionary relationships between organismsTaxonomyThe study of the principles of classificationTaxonClassificatory group
50 Natural Classification Concept of the speciesCapable of breeding to produce fertile offspringHave common ancestryHave very similar genesHierarchy of classificationClosely related species are placed together in groupsClosely related groups are placed together in a larger groupModern classification reflects the evolutionary distance between species
51 Evolutionary treeAny two species alive today will share a common ancestor from the pastThe time when the two species started to evolve separately is a branch point on the tree
52 Progress Questions What is meant by the term classification? What is meant by the term phylogeny?What is the relationship between natural classification and phylogeny?
53 Answers to progress questions What is meant by the term classification?Classification is the sorting of living things into groupsNatural classification does this by grouping things by how closely related they areWhat is meant by the term phylogeny?The study of evolutionary relationships between organismsWhat is the relationship between natural classification and phylogeny?Natural classification groups things according to how closely related they areThis should match the evolutionary tree produced by considering how recently organisms shared a common ancestor.
54 Classifying living things Carl Linnaeus – 18th CenturyDevised a scheme of classificationOrganisms were put into a series of ranked categoriesCategories are taxonomic groups (TAXON)5 kingdom classification
55 Hierarchy of classification DomainKingdomPhylumClassOrderFamilyGenusSpeciesThis is the basic unit of classification
56 TaxonDescriptionKingdomLargest group of organisms sharing a few common features.PhylumMajor subdivision of a kingdom.ClassA group of related orders- subdivision of a phylum.OrderA group of related families- subdivision of a class.FamilyA group of closely related genera- subdivision of an order.GenusA group of related species- subdivision of a family.SpeciesA group of organisms capable of breeding and producing fertile offspring.
57 Hierarchy of classification TaxonNo. of similaritiesSize of groupDegree of relatednessDomainsmallLargeDistant to common ancestorKingdomPhylumClassOrderFamilyGenusSpecieslargeRecent common ancestor
58 Examples of Classification TaxonTigerHumanFruit flyDomainEukaryotaKingdomAnimaliaPhylumChordataArthropodaClassMammaliaInsectaOrderCarnivoraPrimateDipteraFamilyFelidaeHominidaeDrospophilidaeGenusPantheraHomoDrosophilaSpeciestigrissapiensmelanogaster
59 Learning OutcomesOutline the binomial system of nomenclature and the use of scientific (Latin) names for species.Use a dichotomous key to identify a group of at least six plants, animals or micro organisms.Outline the characteristic features of the following five kingdoms: Prokaryotae (Monera), Protoctista, Fungi, Plantae, Animalia.
60 Confusion over common names In North America, this animal is a moose.In Europe, this animal is an elk.In North America, this animal is an elk.In Europe, this animal is a red deer.
61 Binomial Classification Universal system based on Latin namesGeneric nameSpecific name
62 Rules for using systemName printed in Italics, or underlined if hand writtenFirst letter of generic name in capitalsOnce generic name has been used, it can be abbreviated in later text to the first letter.If specific name not known, write sp.If referring to all members of a genus, specific name written in plural spp.
63 Binomial system of nomenclature ExamplesHomo sapiensPanthera leoPanthera tigrisLutra lutra
64 Identifying Living things Dichotomous keyAsks a series of questions in pairsYou are then directed to another question or to an identificationLook at the Classification and Taxonomy fact sheetLook at the example of a classification key as shownOther examplesTextbook pg 207Revision guide pg 77
65 Five Kingdom Classification ProkaryotaeProtoctistaFungiPlantaeAnimalia
66 Prokaryotae Oldest group of organisms on earth Two groups originally recognised but have now been separated into two domainsArchaeaEubacteria (includes cyanobacteria)Distinguishing features of eubacteria (Prokaryotae)Organisms lack nuclei organised within membranes.No envelope-bound organelles.No 9+2 microtubules
68 Fungi Eukaryotic Heterotrophic nutrition Cell walls made of chitin Usually form myceliumCarbohydrate stored as glycogenSexual or asexual reproduction
69 Plantae Features Eukaryotic Multicellular Possesses chlorophyll and other pigmentsAutotrophic nutritionCells walls of celluloseCarbohydrate stored as starch.
70 Animalia Eukaryotic Multi-cellular Heterotrophic nutrition No cell wallsCarbohydrate stored as glycogenDisplay nervous co-ordination
71 Learning OutcomesDiscuss the fact that classification systems were based originally on observable features but that more recent approaches draw on a wider range of evidence to clarify relationships between organisms, including molecular evidence.Compare and contrast the five kingdom and three domain classification systems.
72 Modern Classification In the 19th and early 20th century – classification was based on observable featuresMorphologyEmbryologyAnatomyHomologous featuresEvolutionary origin in the same ancestral structureE.g. pentadactyl limb of tetrapods
73 New developmentsThe following scientific developments can now be used as a method of classifying organismsPrimary structure of proteinsCyctochrome C is a protein used in respirationBy comparing the sequence of amino acids in the primary protein structure can determine how closely related the species are.
74 New developments Scanning Electron Microscopy DNA sequencing Looks at morphology in greater detailDNA sequencingHelps classification to reflect phylogeny using nucleotide sequence data
75 The Three Domains 1990 – Carl Woese New classification system after studying ribosomal RNAArgued that the differences in bacteria were so great they needed separatingBacteria – EubacteriaArchaeae – ArchaebacteriaThis gives three domainsBacteriaArchaeaEukaryotae
76 Why three domains?Eubacteria are prokaryotic and fundamentally different from Archaeae and eukaryotaeArchaeae share characteristics with eukaryotaeRNA polymeraseSimilar DNA replication mechanisms
80 Evolution“Nothing in biology makes sense except in the light of evolution”Theodosius Dobzhansky, 1973.
81 Learning Outcomes Define the term variation. Discuss the fact that variation occurs within as well as between species.Describe the differences between continuous and discontinuous variation, using examples of a range of characteristics found in plants, animals and microorganisms.Explain both genetic and environmental causes of variation.
82 VariationVariation is the differences that exist between individual organisms.Interspecific variation (between species)Differences that are used to assign individuals to different speciesIntraspecific variation (within a species)Individuals of the same species show variationVariation can be inherited or influenced by the environment.
83 Types of variation There are two main types of variation Continuous variationDiscontinuous variationThere are two main causes of variationGenetic variationEnvironmental variation
84 Continuous variationExistence of a range of types between two extremesMost individuals are close to a mean valueLow numbers of individuals at the extremesBoth genes and the environment interact in controlling the featuresExamplesHeight in humansLength of leaves on a bay treeLength of stalk of a toad stool
85 Continuous variationUse a tally chart and plot results in a histogram
86 Discontinuous variation 2 or more distinct categories with no intermediate valuesExamplesEarlobes attached or unattachedBlood groups A, B, AB or oBacteria flagella or no flagellaFlowers colour of petalsGenetically determinedThe environment has little or no effect on discontinuous variation
88 Causes of variation Genetic Variation Environmental Variation Genes inherited from parents provide information used to define our characteristicsEnvironmental VariationGives differences in phenotype (appearance) but not passed on by parents to offspringExamplesSkin colour tans with exposure to sunlightPlant height determined by where the seed lands
89 Learning OutcomesOutline the behavioural, physiological and anatomical (structural) adaptations of organisms to their environments.
90 AdaptationsAdaptations help organisms to cope with environmental stresses and obtain the things they need for survival.They are features which have evolved over time and are continually subjected to selection pressuresAdaptations can beStructuralBehaviouralPhysiologicalbiochemical
91 A well adapted organism List what a well adapted organism must be able to do in order to surviveE.g. find enough food / photosynthesisTry to list 6 things
92 Behavioural adaptation Any aspect of the behaviour of an organism that helps it to survive the conditions it lives in.ExampleDesert rat remains underground during the day
93 Physiological / biochemical adaptations These ensure the correct functioning of all cell processesExampleSome yeast can respire both aerobically and anaerobically depending on the availability of oxygen
94 Anatomical adaptations A structure which enhances the survival of the organismExampleDesert rats have very long loops of henle to aid the reabsorbtion of water.Fennec fox has large ears
95 Pupil Activity Watch the selection of video clips from planet earth Make notes on the adaptations organisms show to their environmentsAlmost a fun gameIdentify the three adaptations for the organisms shown - FUN,
96 Pupil Activity Adaptations of xerophytic plants For the list of adaptations given decide whether they are physiological, behavioural or structural adaptations.Identifying adaptationsLook at the selection of photosFor each organism try to give an adaptations that suits the organism to its habitat.
102 Pupil ActivityCollect a copy of the worksheet on adaptations of xerophytic plantsFor each adaptation given, explain how this adaptation helps the plant to survive.
103 Learning OutcomesExplain the consequences of the four observations made by Darwin in proposing his theory of natural selection.Outline how variation, adaptation and selection are major components of evolutionDefine the term speciation.
104 Evolution and Natural Selection Gradual development of organisms over timeNatural SelectionTheory proposed by Darwin as a mechanism to explain how evolution occurred.
105 Evolution by natural selection Darwin’s four observationsVariation exists among offspringOffspring appear similar to parents and inherit features from themOrganisms have the ability to produce large numbers of offspringPopulations of organisms stay relatively stable over timeDarwin’s conclusionsThere is a struggle to surviveBetter adapted organisms survive and pass on their characteristicsOver time – changes may give rise to a new species
106 The theory of natural selection VariationOverproductionStruggle for existenceSurvival of the fittestAdvantageous features inheritedGradual change in the populationWrite out a short explanation for each of these points.
107 Environmental factors Factors that can limit population size includeAvailability of foodPredatorsDiseaseCompetition for spaceFind a matePhysical and chemical factorsSelection pressureAn environmental factor which determines which species survive
108 SpeciationSpeciation is the formation of a new species from a pre-existing one.If two populations of the same species become isolated from each otherdifferent selection pressures mean that the populations develop different adaptationsSpeciation has occurred when the two populations can no longer breed together to produce fertile offspring.
109 Types of Speciation Allopatric speciation Sympatric speciation GeographicalTwo populations become separatedSympatric speciationtwo species remain in the same geographical area but a reproductive barrier arises, which prevents one member of the population breeding with another
110 Progress QuestionsState the key observations made by Charles Darwin [4 marks]Explain the termsSelection pressureSelective advantage [3 marks]
111 Learning outcomesDiscuss the evidence supporting the theory of evolution, with reference to fossil, DNA and molecular evidence.
112 Fossils Fossil Examples of fossils Remains of organisms that are preserved in sedimentary rocksExamples of fossils
113 Fossil Evidence Fossils show certain facts Questions In the past species were very different than species todayOld species have died outNew species have arisenNew species often similar to old speciesQuestionsWhy does one species die out?Why would a similar one replace it?Did one give rise to the other?
114 BrachiopodsChange gradually over timeCan be used to age rocks
116 Fossil Evidence One of the earliest birds many features that are typical of the reptiles
117 Gaps in the fossil record The fossil record is incomplete for many reasonsOnly the hard parts of the animals become fossilisedFossils can only form under certain conditionsAfter they have formed fossils could become damaged or destroyed by rock movements
118 More recent evidenceBiological molecules provide strong evidence for evolutionMany biological molecules are found in all organismsAll life on earth has a common ancestorClosely related species – more similaritiesCytochrome C shows patterns of changes
119 Protein EvidenceThe primary structure of protein molecules is determined by the sequences of bases in DNAVital proteins e.g. DNA and RNA polymerase are found in all living organisms
120 Differences in coding sequence DNA evidenceSequencing the bases in DNA allows for comparisonComparing other primates with human DNA, shows evolutionary relationshipsDifferences in coding sequenceprimate1.2%Chimpanzee1.6%Gorilla6.6%baboons
121 Progress QuestionsExplain how DNA analysis and biochemistry can be used to clarify the evolutionary relationships between closely related species [5 marks]Explain how fossils can be used as evidence for evolution [3 marks]Explain the significance of fossils such as Archaeopteryx [2 marks]
122 Learning OutcomeDiscuss why the evolution of pesticide resistance in insects and drug resistance in microorganisms has implications for humans
123 Drug resistance in micro-organisms Using antibiotics changes the environment for the bacteriaMutation giving resistance gives individual bacterium a selective advantageIt survivesOver time number of resistant types of bacteria increaseSome antibiotics are now ineffective
124 Arms Race MRSA Methicillin resistant Staphylococcus aureus Developing resistance to an ever increasing range of stronger and stronger anti-biotics
125 Pesticide Resistance A pesticide is a chemical designed to kill pests Insecticide kills insectsInsecticide applies selection pressure on insect populations to develop resistanceDue to short life cycles resistance spreads quickly through the whole population
126 Pesticide resistance Resistance Example Breakdown of insecticide using enzymesModification of target receptor proteins on cell membraneExampleAnopheles mosquitoResistant to DDT and pyrethroids
128 Learning Outcomes Evolution Define the term variation.Discuss the fact that variation occurs within as well as between species.Describe the differences between continuous and discontinuous variation, using examples of a range of characteristics found in plants, animals and microorganisms.Explain both genetic and environmental causes of variation.Outline the behavioural, physiological and anatomical (structural) adaptations of organisms to their environments..Explain the consequences of the four observations made by Darwin in proposing his theory of natural selection.Define the term speciation.Discuss the evidence supporting the theory of evolution, with reference to fossil, DNA and molecular evidence.Outline how variation, adaptation and selection are major components of evolution.Discuss why the evolution of pesticide resistance in insects and drug resistance in microorganisms has implications for humans
129 2.3.4 Conserving Biodiversity Module 3: Biodiversity and Evolution
130 Maintaining Biodiversity Maintaining biodiversity is important for many reasons.Actions to maintain biodiversity must be taken at local, national and global levels.
133 Learning OutcomesOutline the reasons for the conservation of animal and plant species, with reference to economic, ecological, ethical and aesthetic reasons.
134 Definition of conservation Management of human use of the biosphere so that it may yield the greatest sustainable benefit to present generations while maintaining it’s potential to meet the needs and aspirations of future generations.World conservation strategy
135 conservationConservation is the protection of ecosystems, habitats and speciesThese means taking action to halt destruction and extinction
136 Conservation Conservation involves Managing areas of land Taking steps to encourage new habitatsRemoving animals to captivityGrowing plants in cultivation
137 Reasons for conserving species The main reasons given for conserving species areEconomicEcologicalEthicalaesthetic
138 Economic reasons Natural ecosystems provide services ExamplesRegulation of atmosphere and climateFormation and fertilisation of soilRecycling of nutrientsGrowth of timber, food and fuelEcosystems also provide goods such as wood and fish for free.
139 Ecological reasons Keystone Species Photosynthesis Keep ecosystems in balancePhotosynthesisRemoves CO2 from the air and replaces oxygen
140 Ethical reasons Species become extinct as a result of human action Humans have a responsibility to maintain species, ecosystems and habitats for future generationsAll organisms have a right to survive and live in the way to which they have become adapted.
141 Aesthetic Reasons People enjoy Recovery of patients visiting wild placesObserving wildlifeThe large animals are sustained by an interdependent web which includes a huge number of speciesRecovery of patientsWellbeing – physical, intellectual and emotional health
142 Learning OutcomesDiscuss the consequences of global climate change on the biodiversity of plants and animals, with reference to changing patterns of agriculture and spread of disease.Explain the benefits for agriculture of maintaining the biodiversity of animal and plant species.
143 Genetic DiversityGenetic diversity within species allows that species to adapt and evolveThreats to species with a low genetic diversity include:Climate changeIncrease in levels of pollutionEmergence of new diseasesArrival of pest species
144 Stages of human impact on genetic diversity Clearing vegetationReduce the size of natural habitatsReduce population sizeReduce gene pool for speciesDecrease genetic variationDecrease ability of species to evolve
145 Modern AgricultureReduces the variation and genetic diversity of domesticated plants and animals, this has led to the extinction of varieties within a species.ExamplesMonocultureSelective breedingEstimate – one locally adapted breed of animal is lost world wide each week.
146 Climate changeAs climate changes the species are unable to adapt due to the loss of genetic variation.Slow migration of populations, communities and ecosystems towards the polesObstruction to migration includeMajor human developmentsAgricultural landLarge bodies of waterhumans
147 The Golden ToadThe golden toad of Costa Rica may have been driven to extinction by climate change,The toad's demise has been revealed by research into the changing populations of species in Costa Rica.The scientists concluded that rising temperatures may have been to blame.The disappearance of the toad is part of a pattern of change that is affecting not only amphibians but also reptiles and birds as well.The Monte Verde golden toad is a very small toad found in the tropical forests of Monteverde, Costa Rica.It is believed to be extinct since no live specimens have been seen since 1989researchers still hope that it continues to live in underground burrows.
148 AgricultureRead through the list below, decide which of the changes due to global warming would benefit agriculture give reasons!!Higher CO2 levelsHigher temperatureLonger growing seasonsGreater evaporation of waterGreater precipitationSea level riseIncrease in salinity of soil
149 Climate change and agriculture Human diet is limitedThree staple foods – wheat, maize, riceFish stocks – codCrops are genetically uniform and susceptible to diseaseWild varieties hold genes which could vary the genome of our crops
150 Climate change and the spread of disease Migration of insect vectors and diseaseTropical disease spread by Anopheles mosquito and the tsetse fly may become a problem in EuropeClimate change is already responsible for:Epidemic of bird malaria in HawaiiViral distemper among lions in SerengetiBlack Stem Rust in wheat
151 Biodiversity for medicine Potential new medicines from plantsPossible vaccines from wild micro-organismsStudy of traditional medicines
152 Learning OutcomesDescribe the conservation of endangered plant and animal species, both in situ and ex situ, with reference to the advantages and disadvantages of these two approaches.Discuss the role of botanic gardens in the ex situ conservation of rare plant species or plant species extinct in the wild, with reference to seed banks.
153 Introduction - recapThe threats to biodiversity are caused by human activities, which are endangering species directly.Species are now being put at risk from habitat loss, hunting, and damage by introduced species, and loss of disease resistance by pollution.Other species are put at risk if a product from the organism becomes a status symbol or is used in folk medicine
154 Endangered SpeciesEndangered species are those that have such small numbers that they are at risk of extinctionLittle genetic variability leaves them susceptible to genetic and infectious diseases“living dead”
155 Conservation of endangered species The conservation of endangered species can be:In situAnimals and plants are protected in their natural environmentEx situAnimals are cared for in zoological collectionsPlants are cared for in botanical gardens
156 Four key aims of in situ conservation A natural healthy environmentSustainable use of the natural environmentA secure environmental futureEnjoyment of the natural environment
157 National ParksIn South and East Africa National parks protect the largest of the land mammalsA national park should be:ComprehensiveAdequaterepresentative
158 Advantages reserve designation ConservationProtection of biodiversityProtection of cultural and natural heritageAreas maintain ecological integrityOpportunities for sustainable land usesScientific researchMeets need of indigenous people
159 Conflicts with designations Protected animals raid farmlandHunting for foodIllegal harvesting of timbertourism
160 Examples of reserves Phinda reserve – South Africa Release of natural faunaNNR in UK – protect specific speciesSnake’s head fritillaryFritillaria meleagrisMarine Nature reserveSkomer marine nature reserve, pembrokeshire
161 In situ conservation - UK Designated areas in the UKSSSI – sites of special scientific interestNational parksAONB – areas of outstanding natural beautyNNR – National nature reserveESA – Environmentally sensitive areas
162 Ex situ conservation - animals The 3 main aims of zoos are conservation, education and research.Captive Breeding ProgrammesRare and endangered species are bred in captivity
163 Captive breeding programmes Advantages of captive breeding programmesFewer animals need to be caught in the wildReduces the chances of extinctionReintroduction into the wildProblems with captive breeding programmesAfter releaseToo tame or too used to captivity to surviveDifficulties in finding foodThe original threat is still thereInbreeding depression
164 Case Study: Nene Goose (Branta sandivicensis) Largest native bird on Hawaii, it is a non-migratory species, which only lives on the isolated island.C ,000 geesegeeseReason for decline - the introduction of non-native terrestrial predators, e.g. rats, dogs.The mongoose was originally introduced to control the rat numbers, but found the geese and their eggs easier prey (biological control gone wrong again).
165 Case Study: Nene Goose (Branta sandivicensis) Captive breeding programmefemales and 1 malesent to the wildfowl’s and wetlands trust in England.geesein wildfowl sanctuaries around the world.1600 geeserelease back onto HawaiiMeasures were put in place to protect the geese, such as netting around nesting areas, and control of the predatory species.
166 Ex situ - plants Botanical Gardens KEW Gardens Collect seeds from the wildSeeds stored and germinated in protected conditionsCan increase the number of individuals of a species very quicklyKEW Gardensspecies of vascular plantsImportant in maintaining biodiversity and genetic diversity in plants
167 Disadvantages – botanical gardens Collection of wild seeds will cause some disturbanceCollected samples – not representativeSeeds stored may not be viablePlants bred asexually are genetically identical
168 Seed Banks E.g. millennium seed bank, West Sussex Seeds kept in a cold storeThe moisture content of seeds are reduced under low temperature and then frozen.Some specialise in preserving varieties of crop plantsBotanist’s noah’s ark
169 Learning OutcomesDiscuss the importance of international cooperation in species conservation with reference to the Convention in International Trade in Endangered Species (CITES) and the Rio Convention on Biodiversity.
170 International Co-operation The loss of habitat and the number of endangered species is a worldwide problemNeeds a worldwide solution
172 The convention of international trade in endangered species of wild flora and fauna Consists of three Appendices protecting around 25,000-30,000 speciesAimEnsure that international trade in specimens of wildlife does not threaten their survivalCITES main aims involve the regulation and monitoring of international trade
173 CITES appendix 1Appendix I includes species threatened with extinction.Trade in specimens of these species is permitted only in exceptional circumstances.
174 The convention of international trade in endangered species of wild flora and fauna Appendix one includes species that are threatened with extinctionGorillasTigersLeopardsAsiatic lionMonkey puzzle tree Araucaria araucanaCycad Cycas beddomei
179 CITES Appendix 1And finally the pitcher plantNepenthes rajah
180 CITES Appendix 2Appendix II includes species not necessarily threatened with extinction,trade must be controlled in order to avoid utilization incompatible with their survival.
181 CITES Appendix 3This Appendix contains species that are protected in at least one country, which has asked other CITES Parties for assistance in controlling the trade.
182 MammalsThe following entire groups (orders or families) of mammals are included in CITES Appendices I or II:all primatesall cetaceans(whales & dolphins)all cats(leopard, tiger, etc)all bearsall elephantsall rhinoceroses
183 ReptilesThe following entire groups (orders or families) of reptiles are included in CITES Appendices I or II:all crocodylians(alligators, crocodiles, caimans,etc)all sea turtles(Cheloniidae)all Boidae(boas, pythons)
186 Convention on Biological Diversity (CBD) Signed in 1992 at the “Earth Summit” in Rio de JaneiroCoversUse and conservation of biodiversitySustainable developmentco-operation between countries and statesUK government launched the Biodiveristy Action Plan in response to the convention
187 Learning OutcomesDiscuss the significance of environmental impact assessments (including biodiversity estimates) for local authority planning decisions.
188 Environmental Impact Assessment CBD – Agenda 21 – sustainable developmentEcologists sample an areareport on the likely impact of the development on the species and their habitatsDevelopers and plannersTake into account the effects highlighted and seek to minimise them