2 18-1 How Organisms Interact in Communities ObjectivesIdentify the distinguishing features of symbiotic relationshipsSCS: B-6.1
3 Species Evolve in Response to each other Interactions among speciesInsects/flowersCoevolutionPredator/Prey relationshipsPredation is when one organism feeds on another
4 SymbiosisWhen two or more species live together in a close, long-term association.
5 Parasitism – when one organism feeds on and usually live on or in another Example: Ticks and dogsTicks benefit, but dogs do not
6 Mutualism – a symbiotic relationship in which both benefit from the relationship Example: flowers and beesFlowers are pollinated and bees have food
7 Commensalism – a relationship in which one organism benefits and the other neither is benefits or is harmedExample: Spanish moss and treesTrees are not hurt nor benefit, but the moss benefits from additional sunlight
8 18-2 How Competition Shapes Communities ObjectivesDescribe the role of competition in shaping the nature of communitiesDistinguish between fundamental and realized nichesDescribe how competition affects an ecosystemSummarize the importance of biodiversitySCS: B-6.1, 6.2
9 Common Use of Scarce Resources leads to competition Organisms compete for food, space, light, minerals, and waterResources must be in short supply if competition occursCompetition can limit how species use resourcesCompetition can lead to extinction or elimination of a species
10 Niche – the role of a species in a ecosystem How does the organism affect the environmentIf niches overlap it may cause competitionNiches can vary in size
11 Predation can lesson competition Eliminates those species less adaptivePromotes biodiversity
12 18-3 Major Biological Communities ObjectivesRecognize the role of climate in determining the nature of biological communitiesDescribe how elevation and latitude affect the distribution of biomesSummarize the key features of the Earth’s major biomesSCS: B-6.1, 6.2
13 Climate determines where species lives Climate is the prevailing weather conditions of an areaTemperature and moistureTemperature and moisture determine biological communities
14 Types of Terrestrial Biomes TundraTaigaDesertGrasslandTemperate ForestsTropical Rain Forests
16 Tundra extremely short growing season (6 to 10 weeks) long, cold, dark winters (6 to 10 months with mean monthly temperatures below 32° F or 0° C.)low precipitation (less than five inches/year)Animals and animals: Musk ox, artic hare and fox, permafrost (permanently frozen ground)
18 TaigaLong, severe winters and short summers (50 to 100 frost-free days) are characteristic, as is a wide range of temperatures between the lows of winter and highs of summer.Mean annual precipitation is 15 to 20 inches, but low evaporation rates make this a humid climate.Vegetation and Animals: Conifers, beaver, lynx, deer, sparrows…..
20 Deserts Temperature: Average of 38°C (day), average of -3.9°C (night) Precipitation: About 250 mm of rain per year Vegetation: Cacti, small bushes, short grasses Animals in the desert: coyotes, lizards and snakes, insects, and even some birds) are adapted for burrowing to escape the scorching heat of the desert sun
22 GrasslandsTemperature: Dependent on latitude, yearly range can be between -20°C to 30°C Precipitation: About 500 to 900 mm of rain per year Vegetation: Grasses (prairie clover, salvia, oats, wheat, barley, coneflowers)Animals: bison and antelope
24 Temperate ForestsTemperature: -30°C to 30°C, yearly average is 10°C, hot summers, cold winters Precipitation: 750 to 1,500 mm of rain per year Vegetation: Broadleaf trees (oaks, maples, beeches), shrubs, perennial herbs, and mossesAnimals: Deer, raccoons, and salamanders are characteristic inhabitants.
26 Tropical Rain ForestTemperature: 20°C to 25°C, must remain warm and frost-free Precipitation: 2,000 to 10,000 millimeters of rain per year Vegetation: Vines, palm trees, orchids, fernsAnimals and plants: monkeys, cat like mammals, reptiles, insects, diverse flowers, hard wood trees, and medicinal plants