Chapter 18 – Interaction of Living Things

The Web of Life All living things are connected in a web of life Ecology - the study of the interactions of organisms with one another and with their environment An organism’s environment consists of all the living things that affect the organism (2 groups) - biotic and abiotic All living things are connected in a web of life Ecology - the study of the interactions of organisms with one another and with their environment An organism’s environment consists of all the living things that affect the organism (2 groups) - biotic and abiotic

Biotic and Abiotic Biotic - All of the organisms that live together and interact with each other make up biotic part of environment Abiotic - Part of environment that consists of the nonliving factors like water, soil, light, temperature, and air Biotic - All of the organisms that live together and interact with each other make up biotic part of environment Abiotic - Part of environment that consists of the nonliving factors like water, soil, light, temperature, and air

Organization in Environment Environment organized into different levels 1st level is made of an individual organism 2nd level is larger and made of similar organisms that form population 3rd level is made of different populations that form community 4th level is made of a community and abiotic environment that form ecosystem 5th level contains all ecosystems that form biosphere Environment organized into different levels 1st level is made of an individual organism 2nd level is larger and made of similar organisms that form population 3rd level is made of different populations that form community 4th level is made of a community and abiotic environment that form ecosystem 5th level contains all ecosystems that form biosphere

Vocabulary Population - a group of organisms of the same species that live together in a specific (the same) geographical area Community - consists of all of the populations of a species that live in the same habitat and interact with each other Ecosystem - made up of a community of organisms and the abiotic environment of that community Biosphere - part of Earth where life exists: includes all ecosystems for example the deepest parts of the ocean to high in the air where pant spores drift Population - a group of organisms of the same species that live together in a specific (the same) geographical area Community - consists of all of the populations of a species that live in the same habitat and interact with each other Ecosystem - made up of a community of organisms and the abiotic environment of that community Biosphere - part of Earth where life exists: includes all ecosystems for example the deepest parts of the ocean to high in the air where pant spores drift

Living Things Need Energy All living things need energy to survive Organisms are divided into three categories based on how they get energy –Producers –Consumers –Decomposers All living things need energy to survive Organisms are divided into three categories based on how they get energy –Producers –Consumers –Decomposers

Producers Organisms that use sunlight directly to make their food They use a process called photosynthesis Examples are plants, algae, and bacteria Organisms that use sunlight directly to make their food They use a process called photosynthesis Examples are plants, algae, and bacteria

Consumers Organisms that eat their energy Cannot use the sun’s energy to make food like producers can Herbivore - consumer that eats only plants ex. grasshoppers, prairie dogs Carnivore - consumer that eats only animals (meat) ex. coyotes, hawks, badgers Omnivore - consumer that eats both plants and animals ex. grasshopper mouse eats insects, lizards, and grass seeds Scavengers - omnivores that eat dead plants and animals ex. vulture Organisms that eat their energy Cannot use the sun’s energy to make food like producers can Herbivore - consumer that eats only plants ex. grasshoppers, prairie dogs Carnivore - consumer that eats only animals (meat) ex. coyotes, hawks, badgers Omnivore - consumer that eats both plants and animals ex. grasshopper mouse eats insects, lizards, and grass seeds Scavengers - omnivores that eat dead plants and animals ex. vulture

Decomposers Organisms that get energy by breaking down dead organisms Examples are bacteria and fungi Remove stored energy from dead organisms and produce materials like water and carbon dioxide which can be used by other living things picture Organisms that get energy by breaking down dead organisms Examples are bacteria and fungi Remove stored energy from dead organisms and produce materials like water and carbon dioxide which can be used by other living things picture

Food Chains A diagram that shows how energy in food flows from one organism to another, but because there are few organisms that eat only one thing energy flow is more accurate when using a food web picture A diagram that shows how energy in food flows from one organism to another, but because there are few organisms that eat only one thing energy flow is more accurate when using a food web picture

Food Webs A diagram that shows the feeding relationships between organisms in a ecosystem Shows how matter and energy are transferred between organisms A diagram that shows the feeding relationships between organisms in a ecosystem Shows how matter and energy are transferred between organisms

Energy Pyramid A diagram that shows an ecosystem’s loss of energy Less energy at the top A diagram that shows an ecosystem’s loss of energy Less energy at the top

What if an Animal’s Population Decreases? Pics of grey wolves Pg 542 Pics of grey wolves Pg 542

Interactions with the Environment Limiting factor - resource that is so scarce that it limits the size of a population –Food becomes a limiting factor when a population becomes too large for the amount of available food Carrying capacity - the largest population that an environment can support –When a population grows large than its carrying capacity, limiting factors in the environment cause individuals to die off or leave…in turn the population will decrease Limiting factor - resource that is so scarce that it limits the size of a population –Food becomes a limiting factor when a population becomes too large for the amount of available food Carrying capacity - the largest population that an environment can support –When a population grows large than its carrying capacity, limiting factors in the environment cause individuals to die off or leave…in turn the population will decrease

Competition Coexist - some populations share resources so they coexist with each other –When two or more individuals or populations use same resource competition exists Competition can happen within a population or between two different populations Coexist - some populations share resources so they coexist with each other –When two or more individuals or populations use same resource competition exists Competition can happen within a population or between two different populations

Predators and Prey Prey - an organism that is killed and eaten by another organism Predator - an organism that eats all of part of another organism –When bird eats worm, worm is prey and bird is predator Predators and prey adapt to their environment –Examples: cheetahs can run fast to catch their prey, some prey are poisonous or can camouflage themselves to hide from their predators Prey - an organism that is killed and eaten by another organism Predator - an organism that eats all of part of another organism –When bird eats worm, worm is prey and bird is predator Predators and prey adapt to their environment –Examples: cheetahs can run fast to catch their prey, some prey are poisonous or can camouflage themselves to hide from their predators

Symbiosis Symbiosis - a close, long-term relationship between two or more organisms –Mutualism - symbiotic relationship in which both organisms benefit example: anemone and clown fish –Commensalism - symbiotic relationship in which one organism benefits and the other is unaffected example: shark and remora –Parasitism - symbiotic relationship in which one organism benefits and the other is harmed; host is the harmed organism, parasite is the organism that benefits example: tapeworm (parasite) and dog (host) Symbiosis - a close, long-term relationship between two or more organisms –Mutualism - symbiotic relationship in which both organisms benefit example: anemone and clown fish –Commensalism - symbiotic relationship in which one organism benefits and the other is unaffected example: shark and remora –Parasitism - symbiotic relationship in which one organism benefits and the other is harmed; host is the harmed organism, parasite is the organism that benefits example: tapeworm (parasite) and dog (host)

Coevolution Relationships can change over time Coevolution - when a long-term change takes place in two species because of their close interactions with one another Example: ant and acacia tree - ant protects tree by attacking other organisms that come near it and tree makes food for ants; these coevolved over a long period of time to interact with each other Flowers have changed over millions of years to attract pollinators (an organism that carries pollen from one flower to another) Relationships can change over time Coevolution - when a long-term change takes place in two species because of their close interactions with one another Example: ant and acacia tree - ant protects tree by attacking other organisms that come near it and tree makes food for ants; these coevolved over a long period of time to interact with each other Flowers have changed over millions of years to attract pollinators (an organism that carries pollen from one flower to another)