Bio Notes 3 PDF

Ecology -Carl Linnaeus explained the economy of nature -Darwin believed ecology were determined by natural selection and adaptation. -Haeckel talked about the economy of nature and the struggle for existence. -Ellen Richards introduced ecology to the US. Biosphere- Any place where living organis...

Ecology -Carl Linnaeus explained the economy of nature -Darwin believed ecology were determined by natural selection and adaptation. -Haeckel talked about the economy of nature and the struggle for existence. -Ellen Richards introduced ecology to the US. Biosphere- Any place where living organisms are. Oceans, sky land. Includes atmosphere, ecosphere, hydrosphere, lithosphere Whittaker Diagram- This is a graph of temperature vs precipitation which makes clear the different biomes of places. There are different biomes for different models. Aquatic biomes, Land biomes In the ocean different biomes exist based on the depth of the water. Photic is top, aphotic is middle, abyssal is bottom. Gulf Streams: Densities cause movement of winds making the gulf streams. Hot water rises and cold sinks. It moves at around 2 m/s towards Europe. Starts west Africa then up the coasat of the East USA and then up to the north. Provides heat to Europe and northern US. -More biodiversity occurs in the tropics because competition forces organisms to specialize. Abundance occurs because of warm weather and more energy. Evolution occurs faster in the tropics as more species are born and they don’t go extinct as fast. Productivity hypothesis- More light, heat, and precipitation in the tropics with longer growing seasons. This causes greater productivity which promotes more specialization, lower extinction rates, higher population sizes. Stability hypothesis- Tropical climates are less variable and more stable which causes more specialization, lower extinction rates, higher speciation rates. The sun powers the biosphere and plants use the sunlight of visible light to power photosynthesis. Standing crop: the amount of dry producer biomass in the ecosystem at a given time. Gross primary production: Total amount of energy fixed by all autotrophs per unit area and time. Net Primary production: Remaining energy after autotrophs reach their own energy needs. Respiration: intake of oxygen and release of carbon dioxide NPP=GPP- Respiration Open ocean is usually nutrient poor so less standing crops an less NPP. NPP is best in tropics where moisture and temperature are high and good for plants. Earths total NPP= area of ecosystems * NPP of the ecosystem. Total NPP is highest for ocean because it is so big, even though the NPP/land is small in oceans. Carbon source includes emissions from burning fossil fuels, fires, and respiration. Carbon sinks move the carbon. Include oceans, plants, soil. Satellites use remote sensing to measure wavelengths on earth. This assesses carbon productivity by looking at chlorophyll absorbing in blue and red light while reflecting green. High standing crops have high absorption of blue and red and high reflection of green. All of the earth ecological systems are connected. For example, on an island people planted coconut trees which ruined birds habitat which stopped nitrogen in the water from the birds which stopped the food source for manta rays. Population Ecology- Individuals of the same species living in the same place at the same time. Study of populations in relation to their environment. No transfer of energy is 100% efficient. Because of laws of thermodynamics, a constant flow of energy from producers to consumers keeps the ongoing existence of the biosphere. Example is starlings in Rome- Predation, climate, food are all biotic factors that cause them to swarm. Abiotic factors are temperature John Westwood was first to estimate how many species there are. Sir Robert May says we have no way to know how many species there are. Carrying Capacity Population change= (Births -Deaths)+ (Immigrants-Emigrants) Population Stability: Territorial behavior can keep population size relatively stable due to the density-dependent impact. Population Instability: Bacterium: can cause infertility and mote with non-carriers. Nutrinet Limitation: Some organisms are very sensitive to the climate which can cause fertility rate to change based on conditions. Some populations grow exponentially but is usually not sustainable in normal conditions. Carrying capacity is maximum population size in which the population can be sustained. Environmental conditions: The environmental factors that restrict the biotic potential of an organism Ecological Dynamics -1st principle: Everything is ultimately connected to each other Reductionist approach- Look at individual, simple things and start to spread them out. Rutherford says to reduce everything to physics philosophies. Focuses the impacts of different things, food, weather, etc., on the abundance of a species. Holistic approach- Look at everything as a whole. Thinks reduction is too simple to understand complex systems. Focuses on impacts of everything on each other which then could impact abundance. -The Gaia Hypothesis, Very controversial- Life and environment evolved as a connected system and is modified by positive and negative feedback from organisms to survive. The Biosphere is homeostatic and the environment is like a self-maintaining biotic/abiotic organism. Daisyworld simulation- Is proof of the Gaia hypothesis that the daisies interact with each other and provide positive and negative feedback to the environment. Black daisies provide positive feedback on temperature by absorbing photons. White daisies reflect photons & provide negative feedback on temperature Competition- any use of defense of a limited resource that reduces availability of it for other members of the ecosystem. This mean both species will have lower populations when living with each other. Types of competition: Interference: direct competition and interference. Exploitative: One species uses limited resources more efficiently than the other. Apparent: two species in the same habitat share a higher tropic-level predator, when two species share a predator and one cause the predator populatoin to change. Interspecific competition: Competition between species for shared researches such as food, space, etc. Intraspecific competition: Competition between members of the same species for resources. Similar species living in same habitats utilize different resources, segregate by: 1. Food 2. Space 3. Time. Co-Occurence results in character: When they live together, the species change their characteristics to adapt. Competitive Exclusion Principle: Gause says that if 2 species live in stable association they must posses different ecological niches.