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Explore the importance of genetic, species, and habitat diversity in ecosystems. Learn about biodiversity scales, stressors, species interbreeding, and niche roles. Engage in practical exercises to calculate diversity indexes.
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Introduction ofBiodiversity • Biodiversity- ecosystem, species, genetic • Genetic diversity- measure ofgenetic variation among individuals in a population. • High genetic diversity = better ableto respond tochange • Species diversity- number of species in a region or in a particular type of habitat. • High = More productive &resilient • Ex: number of plants species inunderstory • Habitat diversity-range • of habitats present in aregion
How manyspecies? • Species: a group that is distinct from other groups in terms of size, behavior, orbiochemical properties and can interbreed to produce viable offspring. • The number of species in a given area isthe most common measure of biodiversity (the quantity and variety within anecosystem). • Scientists have named about 2 millionspecies and approximate there are 5-100 million on Earth. The accepted estimate is set at 10 million.
Biodiversity • Variety of life onEarth
Three Scales ofBiodiversity • 1. Genetic Diversity- genetic variation among individuals ina population • Example: bloodtype
The more genetically diverse a population is the better itcan respond to environmentalstressors • Examples ofStressors • Physical Stress (naturaldisasters) • Ex: tornadoes orflooding • Wildfires • AirQuality • Thermalstress • Radiation • Climatic (light,temperature) • Biological (predation, competition,parasitism, lack ofmates) • Noise
Three Scales ofBiodiversity • 2. Species Diversity- number of species in a region or habitat (ina community orecosystem) • Whoremembersfrombiology:Whatisaspecies? • Can interbreedand produce viableoffspring • WhatisthemostcommonspeciesonEarth? • Nematodes are the most numerically abundant animals onEarth
Most commonorganism: the bacterium Pelagibacterubique • 1/3rd of allsingle-celled • ocean organisms
This about this example: Ligers (offspring between a male lion and a tigress) are usually larger than their parents, so the breeding naturally puts the mother tigresses at great risk in carrying the young, and may require C-section deliveries that can kill the tigresses. Additionally, not all ligers can be healthy, for they can develop neurological disorders. Ligers are notfertile!! • So how do you get anotherliger?
Three Scales ofBiodiversity • 3. Habitat/Ecosystem Diversity- variety of habitats that exist within a givenregion
Organismal ecology: habitat • Habitat = the environment in which an organism lives • Includes living and nonliving elements • Scale-dependent: from square meters to miles • Availability and quality of habitat are crucial to an organism’s well-being • Niche = an organism’s use of resources and its functional role in a community • Habitat use, food selection, role in energy and nutrient flow • Interactions with other individuals • Specialists = species with narrow niches and very specific requirements • Extremely good at what they do, but vulnerable to change • Generalists = species with broad niches that can use a wide array of habitats and resources • Able to live in many different places
Species richness- number of species in a givenarea. • Species evenness- measure of whether a particular ecosystem is numerically dominated by one species or are all represented by similar numbers ofindividuals. • Species Dominance- most abundantspecies Community 1has Goodevenness Both have samerichness p.151
Lower values indicate morediversity. Higher values indicate lessdiversity.
TextbookPractice p.152 Get into your group or witha buddy and workitout You CAN do it!!!
With your buddy orgroup….. • Fill out thetable • n(n-1) • Species richness: what#? • Evenness: high orlow? • Dominance: high orlow? ? ? ?
With your buddy orgroup….. • Fill out thetable • n(n-1) • Species richness: what#? • Evenness: high orlow? • Dominance: high orlow? ? ? ?
Nowthatyouhavethenumbers….Dothemath https://studylib.net/doc/7712266/ap-simpson-diversity-index-lab-11-12
Nowthatyouhavethenumbers….Dothemath https://studylib.net/doc/7712266/ap-simpson-diversity-index-lab-11-12