Ecology Symbiosis and Succession

Ecology What is ecology? The study of organisms and how they interact with each other and their environment (the ecosystem) A relatively new field of science

Ecosystems All living and nonliving components Balance between producers and consumers Specialists and generalists

Ecosystems Living things fill various niches A niche is the way of life or the job filled by an organism in its ecosystem Example: –A rabbit fills the niche of an herbivore and it is prey for carnivores

Symbiosis in the Ecosystem Close relationship between two different species There are four types –Mutualism –Commensalism –Predation –Parasitism

Types of Symbiosis –Mutualism is when both species benefit –Commensalism is when one benefits and the other is unaffected –Predation is when one species actively kills and eats the other –Parasitism is when one species benefits and the other is harmed, but not killed (at least not right away!)

Mimicry and Camouflage Survival techniques Some species use camouflage to blend into their surroundings Others use scare tactics to mimic a poisonous organism or a predator

Range of Tolerance The range of environmental factors in which an organism can survive Can be increased if adjusted slowly If factors change too quickly for an organism to acclimate, it may die

Human Impact Humans are changing the habitats all over the earth Rainforests are being destroyed by thousands of acres every minute –Fuel wood –Illegal drugs –Cattle ranching –Development

Global Warming and the Greenhouse Effect The earth has heated up (become tropical) several times in its history The earth has had several ice ages We are currently in a warm, interglacial period

Global Warming and the Greenhouse Effect Certain gases in the atmosphere act like the glass of a greenhouse –They let the sunlight in, but do not let the heat escape

Global Warming and the Greenhouse Effect CO 2, water vapor, & methane are a few such gases Also, ozone helps shield us from ultra violet rays to keep us from getting too much heat CFCs are chemicals that harm the ozone layer

Global Warming and the Greenhouse Effect The Greenhouse Effect is the theory that humans are speeding up the natural process by our activities

Human Activities may increase the Greenhouse Effect Burning fossil fuels (gas, oil, coal) releases CO 2 CO 2 is being added faster than it can be recycled by photosynthesis CFCs are released when we use refrigerants and certain aerosols

The Greenhouse Effect

Succession The sequence that living things arrive in an ecosystem –Primary succession begins with bare rock –Secondary succession begins after a natural or man-made disaster. Soil is already present. Example: Lichen can grow where there is only rock.

Succession Primary succession –Lichen & mosses Break down rock to begin forming soil –Grasses –Shrubs –Trees Secondary succession –Grasses –Shrubs –Trees

Stability in the Environment When predators and prey are in balance, there is more diversity of species. When a disturbance occurs, the stability is altered Example: –Humans may remove all predators from an area and the prey exceed their carrying capacity.