introduction to ecology chapter 19. 19.1 ecology the study of the interactions between organisms and...
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Introduction to EcologyIntroduction to Ecology
Chapter 19Chapter 19
19.1 Ecology19.1 Ecology
The study of the interactions between The study of the interactions between organisms and the living & nonliving parts of organisms and the living & nonliving parts of the environmentthe environment
Humans have always needed to understand Humans have always needed to understand ecology in order to surviveecology in order to survive
Today’s EnvironmentToday’s Environment
Early human cultures were Hunter-Gatherers (relied on Early human cultures were Hunter-Gatherers (relied on practical knowledge about the environment)practical knowledge about the environment)
Current human cultures need to Current human cultures need to
understand the critical impact they understand the critical impact they
have on the Earth (depletion of have on the Earth (depletion of
natural resources)natural resources)
Human PopulationHuman Population
The human population has steadily increasedThe human population has steadily increased
There was a rapid increase after the industrial There was a rapid increase after the industrial revolution (better hygiene, transportation, revolution (better hygiene, transportation, vaccinations, food harvest and shipment)vaccinations, food harvest and shipment)
According to the U.N., the world population According to the U.N., the world population could be between 7.8 – 12.5 billion by 2050could be between 7.8 – 12.5 billion by 2050
Effects of the Human PopulationEffects of the Human Population
As the human population continues to grow, As the human population continues to grow, we increase the demand for Earth’s resourceswe increase the demand for Earth’s resources
Since all life is interconnected, human Since all life is interconnected, human destruction of habitats and contamination from destruction of habitats and contamination from our pollution will have an impact on all living our pollution will have an impact on all living organismsorganisms
The Sixth Mass ExtinctionThe Sixth Mass Extinction
According to fossil records, there have been 5 According to fossil records, there have been 5 mass extinctions in the pastmass extinctions in the past
Currently, we are experiencing the 6Currently, we are experiencing the 6 thth mass mass extinction!extinction!
The overpopulation of humans is causing The overpopulation of humans is causing species to become extinct on a daily basis species to become extinct on a daily basis
Ozone Depletion Ozone Depletion
Ozone layer protects Ozone layer protects living organisms from living organisms from harmful UV radiationharmful UV radiation
Chlorofluorocarbons Chlorofluorocarbons (CFC’s) chemically (CFC’s) chemically react with the ozone and react with the ozone and destroy itdestroy it
Ozone DepletionOzone Depletion
Although the depletion occurs over most of the Although the depletion occurs over most of the planet, it is most concentrated over Antarcticaplanet, it is most concentrated over Antarctica
The ozone hole led to the ban of CFC’s in The ozone hole led to the ban of CFC’s in 19921992
Currently, 1% of UV rays reaches Currently, 1% of UV rays reaches Earths surface and causes ½ million Earths surface and causes ½ million cases of skin cancer each yearcases of skin cancer each year
Climatic ChangesClimatic Changes
Greenhouse EffectGreenhouse Effect: carbon : carbon dioxide and water vapor in dioxide and water vapor in the atmosphere redirect the atmosphere redirect Earth’s reflected heat and Earth’s reflected heat and keep the planet warm keep the planet warm enough to sustain lifeenough to sustain life
Human activities are Human activities are continually increasing the continually increasing the amount of COamount of CO2 2 in the in the
atmosphereatmosphere
Global WarmingGlobal Warming
As fossil fuels are burned, COAs fossil fuels are burned, CO2 2 is releasedis released
More people + more fossil fuels being used = a More people + more fossil fuels being used = a warmer planetwarmer planet
More COMore CO2 2 in the atmosphere results in more in the atmosphere results in more
heat being redirected back at our planetheat being redirected back at our planet
Impacts of Global WarmingImpacts of Global Warming
The average global temperature will increase 3-8The average global temperature will increase 3-8º F º F by 2100by 2100
Polar ice caps are already melting faster than Polar ice caps are already melting faster than expectedexpected
Changes in rainfall and weather Changes in rainfall and weather
patterns will lead to famine, patterns will lead to famine,
starvation, and diseasestarvation, and disease
Levels of Organization in EcologyLevels of Organization in Ecology
The BiosphereThe Biosphere
Where all life is found on Where all life is found on EarthEarth
Extends 8-10 km above Extends 8-10 km above Earth’s surface and below Earth’s surface and below the ocean into the deepest the ocean into the deepest partsparts
Most organisms are found Most organisms are found within a few meters of the within a few meters of the surface of the land or oceanssurface of the land or oceans
EcosystemsEcosystems
Includes all of the organisms (biotic factors) Includes all of the organisms (biotic factors) and the nonliving components (abiotic factors) and the nonliving components (abiotic factors) in a particular placein a particular place
Example: a pond ecosystemExample: a pond ecosystem
CommunityCommunity
All of the interacting All of the interacting organisms living in an organisms living in an areaarea
Ecologists study how Ecologists study how species interact and how species interact and how these interactions these interactions influence the entire influence the entire communitycommunity
PopulationPopulation
All the members of a species that live in the All the members of a species that live in the same place at the same timesame place at the same time
OrganismOrganism
Refers to a living thingRefers to a living thing
Ecologists study the adaptations that an Ecologists study the adaptations that an organism has that helps it overcome the organism has that helps it overcome the challenges in its environmentchallenges in its environment
Key ThemeKey Theme All life is interconnected! All life is interconnected!
No organism is isolated!No organism is isolated!
Survival of a species Survival of a species (including humans) depends (including humans) depends on interdependenceon interdependence
Example: humans could not Example: humans could not survive without the survive without the nitrogen-fixing bacteria that nitrogen-fixing bacteria that live in the roots of legume live in the roots of legume plantsplants
Disturbances in EcosystemsDisturbances in Ecosystems
One change in an ecosystem will affect many One change in an ecosystem will affect many speciesspecies
Example: logging a forest (results in less Example: logging a forest (results in less habitat for all animal species, increases runoff habitat for all animal species, increases runoff that leads to water pollution, less trees using that leads to water pollution, less trees using the atmospheric COthe atmospheric CO2 2 , etc.), etc.)
Ecological ModelsEcological Models
Models are often used when studying Models are often used when studying ecosystemsecosystems
Can be graphs, diagrams, or mathematical Can be graphs, diagrams, or mathematical equationsequations
19.2 Ecology of Organisms19.2 Ecology of Organisms
Where an organism lives depends on its Where an organism lives depends on its evolutionary history, its tolerances and evolutionary history, its tolerances and requirements, the history and conditions of its requirements, the history and conditions of its habitat, and many other factorshabitat, and many other factors
Biotic and Abiotic FactorsBiotic and Abiotic Factors
Biotic factors-Biotic factors- includes the living and once includes the living and once living componentsliving components
Abiotic factors-Abiotic factors- nonliving components such as nonliving components such as the physical and chemical characteristics of the the physical and chemical characteristics of the environmentenvironment
The Changing EnvironmentThe Changing Environment
Abiotic factors are always changing (daily Abiotic factors are always changing (daily temperature changes, rainfall, seasons, etc) temperature changes, rainfall, seasons, etc)
Organisms are adapted to function within a Organisms are adapted to function within a specific range of temperaturesspecific range of temperatures
An organism cannot survive in areas An organism cannot survive in areas where the temperatures are beyond its where the temperatures are beyond its
tolerancetolerance
AcclimationAcclimation
An organism’s adjustment to an abiotic factorAn organism’s adjustment to an abiotic factor
Occurs within the lifetime of an individual Occurs within the lifetime of an individual (NOT an adaptation!)(NOT an adaptation!)
Example: goldfish raised at higher temps. will Example: goldfish raised at higher temps. will have a different tolerance curvehave a different tolerance curve
Control of Internal ConditionsControl of Internal Conditions
ConformersConformers: organisms that don’t regulate : organisms that don’t regulate their internal conditions (example: desert their internal conditions (example: desert lizards)lizards)
RegulatorsRegulators: organisms that use energy to : organisms that use energy to control some of their internal conditions control some of their internal conditions (example: mammals)(example: mammals)
Escape from Unsuitable ConditionsEscape from Unsuitable Conditions
DormancyDormancy: a state of reduced activity during : a state of reduced activity during periods of unfavorable environmental periods of unfavorable environmental conditionsconditions
Examples: hibernation and estivationExamples: hibernation and estivation
MigrationMigration
Moving to a more favorable habitat to escape Moving to a more favorable habitat to escape unfavorable conditionsunfavorable conditions
Example: bird migrationExample: bird migration
ResourcesResources
Refers to the energy and materials a species Refers to the energy and materials a species needs to surviveneeds to survive
Includes food, nesting sites, territory, water, Includes food, nesting sites, territory, water, sunlight, optimal temperature rangesunlight, optimal temperature range
The NicheThe Niche
A species way of life or its role in the A species way of life or its role in the environmentenvironment
Includes the range of conditions the species Includes the range of conditions the species can tolerate, how it obtains its resources, the can tolerate, how it obtains its resources, the number of offspring, time of reproduction, etc.number of offspring, time of reproduction, etc.
Fundamental vs. Realized NicheFundamental vs. Realized Niche
Fundamental niche-Fundamental niche- the entire range of the entire range of conditions and resources that a species could conditions and resources that a species could potentially utilize (very broad)potentially utilize (very broad)
Realized niche-Realized niche- includes what is actually used includes what is actually used by a species by a species
Niche DifferencesNiche Differences
Generalists: species with Generalists: species with broad niches (can tolerate a broad niches (can tolerate a range of conditions and use range of conditions and use a variety of resources) a variety of resources) example: mothsexample: moths
Specialists: species with Specialists: species with narrow niches (feed on a narrow niches (feed on a limited type of resources) limited type of resources) example: butterfliesexample: butterflies