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Principles of Ecology. What’s the BIG IDEA?. What’s the BIG IDEA? Energy is required to cycle materials through living and nonliving systems. Organisms and their Relationships. MAIN IDEA: Biotic and abiotic factors interact in complex ways in communities and ecosystems.
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What’s the BIG IDEA? What’s the BIG IDEA? Energy is required to cycle materials through living and nonliving systems.
Organisms and their Relationships • MAIN IDEA: Biotic and abiotic factors interact in complex ways in communities and ecosystems.
What is Ecology? • Study of interactions between organisms, their environments, and different species • Organisms are observed in their own environments • Effects of biotic and abiotic things are studied
Ecologists (Don’t copy) • 1866 – Ernst Haeckel introduced the word ecology • Since then, national government has worked to protect the environment: • National parks • Damage to environment studied • Laws to protect the environment
What Do Ecologists Do? (Don’t copy) • What are important things in the environment people might study? • Why are they important?
The Biosphere • Thin layer around Earth that supports life • Extends several km above Earth’s surface, and several km below the ocean’s surface • Includes any place where life is found • Includes biotic (living) and abiotic (nonliving) things
Levels of Organization (Hierarchy) • Simplest complex: organism, population, biological community, ecosystem, biome, biosphere
Population • Organisms of the same species in the same location at the same time • Ex: the goose population in Nomahegan Park in 2007 • Members compete for the same resources • If becomes too large, some may die until the environment can support it again
Community • All the populations in the same area at the same time • Example? • Populations can interact and sometimes compete for the same resources
Ecosystem • Community + all abiotic factors that affect it • No size limit or boundaries; can be large or small (Watchung Reservation or a puddle) • some overlap (ocean and shoreline)
Biome • Large group of ecosystems with the same or similar climate, characteristics, and communities • Ex: desert, rainforest, ocean
Biosphere • Largest level of organization • Includes ALL of the biomes • Most complex
Create! • Make a diagram, structure, rhyme, song, etc. to show the levels of organization. Include a specific example. • Work in a small group. • You will present your creation!
4 Main Characteristics of Ecosystems • Organisms interact with each other and abiotic factors. • Energy flows by being transferred through organisms. • Nutrients and other materials are cycled. • Ecosystems change.
Factor 1: Interactions • Interactions occur within ecosystems and communities.
Community Interactions • Organisms interact for survival. • Types of interactions: • Competition • Predation • Symbiotic
Competition • More than 1 organism uses a resource at one time • May compete for food, sunlight (plants), water, mates, etc. • Competition – fierce when resources are limited • Weaker organisms may die or leave area
Types of Competition (DON’T COPY) • Interspecific – between different species • Ex: snail and river turtle compete for tape grass. • Intraspecific – within one species • Deer competing for limited resources as their land shrinks due to development by humans
Predation • Eating another organism • Predator – usually an animal; exception is the venus fly trap • Prey – can be plants or animals • What are some adaptations of predators and prey?
Predator/Prey Adaptations • Camouflage (cryptic coloration) • Warning coloration – poisons, stingers • Chemical defenses – poisons, toxins • Mimicry – resemble distasteful models (butterflies, wasps and bees)
Plant Prey Protection • Morphological (structural) – thorns, spines, plant hairs, etc • Chemical defenses- may be poisons or other toxins • Some herbivores have adapted to be able to eat these
Symbiotic Relationships • Close relationship – organisms live together • Mutualism • Commensalism • Parasitism Page 93
Mutualism • Both organisms benefit from the relationship • Ex: birds, insects, bats and flowering plants • Lichens (alga and fungus – food/moisture) • Grazing animals and birds (cattle and egrets)
Commensalism • One benefits, the other is not helped or harmed • Ex: barnacles attach to whales for a ride and protection from predators, new food resources, water circulation, spread of genes to new areas for variation • Shark and remoras
Parasitism • One benefits (parasite), the other is harmed (host) • Host is often indirectly killed because it becomes so weak • External – lice • Internal – eggs often laid in other species and feed off of them (heartworm, tapeworm, strongyles) • Parasitic plant (dodder) obtains food from host plant b/c no chlorophyll
Ecosystem Interactions • Interactions occur between organisms and their environment. • A habitat is an area where an organism lives. • A niche is the role or position that an organism has in its environment. • Ex: requirements for space, food, temperature, etc.
Importance of a niche (Don’t copy) • Niche of one bird species is to eat beetles, while another bird species can eat spiders in the area. • Only one type of organism occupies its niche in a community. Competing species often have slightly different food sources, predators, or hunting times, for example. • This helps to eliminate competitive exclusion in nature. (Resources are partitioned to all members of a community)
What about you? • What is your habitat? • Describe your niche.
Flow of Energy in an Ecosystem • MAIN IDEA: Autotrophs capture energy, making it available for all members of a food web.
4 Main Characteristics of Ecosystems • Organisms interact with each other and abiotic factors. • Energy flows by being transferred through organisms. • Nutrients and other materials are cycled. • Ecosystems change.
DO NOW • Can energy be created or destroyed? Where is energy stored so living things can use it? • Make a food web connecting the following: A mouse eats oak acorns, but is eaten by a snake and a hawk. The hawk and snake both eat a smaller bird, and the snake also eats a salamander. The salamander and small bird eat insects, which eat pine cones. All organisms are broken down by fungus and bacteria.
Energy in an Ecosystem • Energy cannot be created or destroyed • Energy CAN be stored in matter – chemical energy in food • Energy flows through ecosystems, from sun producers consumers
Autotrophs vs. Heterotrophs(Don’t copy) • Different organisms – different sources of energy • Autotrophs – make own food; producers • Basis of all ecosystems; make energy available for ALL organisms • Photosynthetic – use sun’s energy • Chemosynthetic – uses chemical energy • Heterotrophs - consumers
Types of Heterotrophs(Don’t copy) • Herbivores – only eat plants • Ex: cow, horse, rabbit • Carnivores – eat other heterotrophs (meat) • Ex: cat, dog, lion • Omnivores – eat plants and animals • Ex: bear, human
Types of Heterotrophs cont’d • Detritivores – eats dead, organic matter (detritus – waste, dead organisms, etc) and makes nutrients available for other organisms • Ex: worms, some insects • Decomposers – break down dead organisms compounds and nutrients • Ex: fungi, bacteria
Models of Energy Flow • Show energy movement from one trophic level (step in food chains/webs) to the next • 1st trophic level = autotrophs • All other levels = heterotrophs • Organisms in one trophic level get their energy from level before them
Food Chains/Webs • Food chain – Simple model of energy transfer • Ex: grass zebra lion • Arrows point FROM food TO what eats it • Starts with autotroph, ends with heterotroph
Food Chains/Webs • REALLY – organisms eat more that one other organism, and are eaten by more than one organism • Food web – interconnected food chains, showing all energy pathways in a community