Introduction to Ecology Chapter 19. 19.1 Ecology The study of the interactions between organisms and the living & nonliving parts of the environment The.

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