Interactions of Life Ecology unit: Chapter 9 ECOLOGY: the study of interactions that occur among organisms and their environments
Birds are a help to the rhinoceros They feed on ticks and other parasites plucked from the rhino’s hide. When the birds sense danger, they fly off, giving the rhino an early warning. Describe how a familiar bird, insect, or other animal depend on other organisms
Living Earth • The part of Earth that supports life is the biosphere • Includes the top portion of Earth’s crust, all the waters that cover Earth’s surface, and the atmosphere that surrounds Earth.
Different Environments in Biosphere • The biosphere is made up of different environments that are home to different kinds of organisms. Examples • Desert • Tropical Rain forest • Coral Reefs • Arctic regions
An ecosystemconsists of all the organisms living in an area + the nonliving parts of that environment ABIOTIC FACTORS Non-living parts of the environment BIOTIC FACTORS Living things in the environment Ecosystems
Abiotic or Biotic? B) C) A) D) F) E)
A population is made up of all organisms of the SAME species that live in an area at the same time. For example, all the bison in a prairie ecosystem are one population. All the cowbirds are a different population. The grasshoppers make up another population. Populations
Community • A community is ALL the populations of all species living in an ecosystem. • An arctic community might include populations of fish, seals that eat fish, and polar bears that hunt and eat seals.
This figure shows how organisms, populations, communities, and ecosystems are related.
Habitat • The place in which an organism lives is called its habitat • An organism’s habitat provides: • the kinds of food and shelter • the temperature • amount of moisture the organism needs to survive.
Habitat • The salamander’s habitat is the forest floor, beneath fallen leaves and twigs. • avoid sunlight and seek damp, dark places.
Competition • Competition: when two or more organisms seek the same resource at the same time • Food and Space • Organisms require food, water and living space, however sometimes organisms don’t always have enough • Ex: Woodpeckers must compete with each other for nesting spots.
Growth limits • Competition limits population size • Ex: nesting spaces limited- woodpeckers not able to raise young • Food becomes scarce- woodpeckers cannot survive and reproduce • most intense competition is usually among individuals of the same species • need the same kinds of food and shelter.
Limiting factors • A limiting factoris anything that restricts the number of individuals in a population. • Limiting factors--living and nonliving features of the ecosystem. • Availability of food, water, living space, mates, nesting sites and other resources • EX: Lack of rain • Limits plant growth-plants produce fewer seeds-limiting factor for mice that eats these seeds limiting factor for hawks and owls (feed on mice)
Populations • Ex: Gila woodpecker abandons its nest— owls, flycatchers, snakes, and lizards might compete for the shelter of the empty hole. 2 Growth Limits • Competition also takes place among different species.
Populations 2 Carrying Capacity • Carrying capacity is the largest number of individuals of one species that an ecosystem can support over time. • If a population begins to exceed the environment’s carrying capacity, some individuals will not have enough resources • die or be forced to move elsewhere. Click image to view movie.
Predator/Prey Cycles • Predator: capture and eat other consumers • (consumers: organisms that eat other organisms) • EX: LYNX • Prey: organism that is captured by the predator • EX: HARES
Graph of Data What is the pattern between the population numbers of the lynx and the hares? What happens when a population exceeds carrying capacity?
Questions • What is the pattern between the population numbers of the lynx and the hares? • # of hares increase, # of lynx increases-- # hare decreases, # of lynx decrease • What happens when a population exceeds carrying capacity? • May not be enough resources to support all members of the population. Its likely that members will begin to die from lack of resources such as food and water.
Interactions within communities • All organisms need ENERGY (chemical bonds in food-mostly sugar) • How do they obtain this energy? • How do producers get energy different than consumers?
4 categories of consumers • Herbivores: Eat only plants (vegetarians) • EX: rabbits, deer • Carnivores: Eat other animals • EX: Frog and spiders (eat insects) • Omnivores: Eat plants and animals • EX: pigs and most humans • Decomposers: Eat waste and dead organisms (Absorb and break down dead matter and recycles it back into the environment) • EX: fungi, bacteria, earthworms
SYMBIOTIC RELATIONSHIPS • Symbiosis: Any close relationship between species • Mutualism (+/+) • Both organisms benefit • Commensalism (+/0) • One organism benefits and the other is unharmed • Parasitism (+/-) • One organism benefits and the other is harmed
Mutualism(+/+) • EX: Bee and a flower • Bees fly from flower to flower gathering nectar, which they make into food, benefiting the bees. When they land in a flower, the bees get some pollen on their hairy bodies, and when they land in the next flower, some of the pollen from the first one rubs off, pollinating* the plant. This benefits the plants. In this symbiotic relationship, the bees get to eat, and the flowering plants get to reproduce.
Commensalism(+/o) -Clown fish and Sea Anemones • Anemones use their tentacles to capture shrimp, fish, and other small animals to eat. The clown fish can swim among the tentacles without being harmed. The anemones tentacles protect the clown fish from the predator. Clown fish are protected but the anemones is not helped or hurt
Parasitism (+/-) • Parasite (+) / Host (-) can affect its growth, ability to reproduce, and survival. • EX: Tapeworm and • Humans (intestines) • Tapeworms are segmented flatworms that attach themselves to the insides of the intestines of animals such as cows, pigs, and humans. They get food by eating the host's partly digested food, depriving the host of nutrients. The tapeworm benefits, while the host (human) is harmed
Niches • An organisms role in its environment • how it gets its food, shelter, finds a mate, cares for its young and avoids danger • How do Predator and Prey fit in a niche? • Predators hunt and captures the prey. Prey’s niche includes how it avoids being eaten (hiding, camouflage) • How do species in a niche cooperate? • Cooperation occurs when organisms work together in ways to improve survival • Warning/Alerting other organisms of danger, living groups to care for young, hunting in packs
Describe the habitat and niche • An aquarium with snails and algae • Habitat: aquarium-freshwater for both organisms • Snails niche: feeds on algae, shelters under rocks or in aquarium plants • Algae niche: uses photosynthesis, obtains nutrients from water.