Introduction to Ecology and the Biosphere The Scope of Ecology

Transcription

1 Introduction to Ecology and the Biosphere The Scope of Ecology

2 Overview: The Scope of Ecology Ecology The word Ecology was first coined in 1866 by the German biologist Ernest Haeckel Haeckel saw the living world as a household with an economy in which each organism had a part. 2

3 Overview: The Scope of Ecology Ecology Greek word oikos means home Same root word as economy Greek word logos means study of wisdom oikos logos to study the wisdom of the home Ecology the study of the household of nature 3

4 Overview: The Scope of Ecology Ecology The scientific study of the interactions between organisms and between organisms and the environment A complex and critical area of biology There are 3 key words in the definition: Scientific Environment Interactions 4

5 Overview: Ecology is Scientific The scientific nature of ecology involves using observations and experiments to test hypothetical explanations of ecological phenomena 5

6 Overview: Ecology is Scientific At all levels small to great Laboratory Field Natural trajectory Natural snapshot 6

7 Overview: Ecology is Scientific Mathematical models Used to simulate large-scale experiments that are impossible to conduct in the field; however, the basic information on which the models are based must be obtained through fieldwork. Statistical programs 7

8 Overview: Ecology is Scientific It is a multidisciplinary field examining questions from all areas of biology Zoology Botany Genetics Evolution Microbiology Physiology Ethology 8

9 Overview: Ecology is Scientific As well as many physical and social sciences Geology Geography Economics Climatology Chemistry Law/politics Astronomy Physics Mathematics Archeology Anthropology 9

10 Overview: Ecology is Scientific Most importantly; ecology is a branch of evolutionary theory Must understand Natural Selection Must understand Fitness 10

11 Ecology studies the Environment The environment of an organism includes both biotic and abiotic components. Biotic components - include all other organisms that are a part of any individual organism s environment Abiotic components are the nonliving chemical and physical factors (e.g., temperature, light, water, nutrients) to which and organism is exposed 11

12 Ecology studies Interactions The interactions between organisms and their environments include: how the environment affects an organism how an organism can change the environment. 12

13 Ecology studies Interactions How can the environment affect an organism? Shelter Flooding Temperature Ex: The distribution of organisms is limited by their tolerance of abiotic conditions Plants in desert 13

14 Ecology studies Interactions How can an organism affect or change the environment? Hmmm? Example #1: Photosynthetic bacteria began to use sunlight for energy about three billion years ago Oxygen, a by-product of photosynthesis, accumulated and resulted in an aerobic atmosphere Example #2: The shading of the forest floor by trees Plants require sunlight to survive The shading by the trees sometimes makes the floor unsuitable for their offspring to survive. 14

15 Overview: The Scope of Ecology Ecology the study of the household of nature Interactions occur across a hierarchy of scales From organismal level to global level Ecologists then specialize at these different levels. Hierarchy of Life Review Organism Population Community Ecosystem Biome Biosphere 15

16 Overview: The Scope of Ecology Organismal Ecology Studies an organism's structure (morphology, anatomy) physiology (function), evolution and behavior. Organism any individual living thing How do abiotic factors limit distribution? 16

17 Overview: The Scope of Ecology Population Ecology Studies the factors that affect population size, density, distribution, and age structure. Population all the individuals of the same species in a defined area. How many nesting Blue Footed Boobies will nest in one area? 17

18 Overview: The Scope of Ecology Community Ecology Studies how interactions between different species affect community structure and organization These interactions determine the distribution of organisms and their abundance Examples of interactions: Predation an interaction between species in which one eats the other (predator/prey) Competition an interaction between individuals or species in which one competes with the other for resources Community all of the populations in a defined area What happens when wolves are over hunted? 18

19 Overview: The Scope of Ecology Ecosystem Ecology Studies energy flow and chemical cycling between organisms and the environment. Ecosystem all of the biotic and abiotic factors in a defined area. The combination of the community (biotic) and the physical (abiotic) environmental factors. Biomes - A large community of plants and animals that occupies a distinct region. Why does it snow more around the Great Lakes? 19

20 Overview: The Scope of Ecology Landscape/Seascape Ecology Studies factors controlling exchanges of energy, materials, and organisms across multiple ecosystems. Landscape/Seascape mosaic of connected ecosystems. How do roads, pipelines or fences might form barriers to movement of shy or less agile animals. 20

21 21 Overview: The Scope of Ecology Global (Biosphere) Ecology Studies how regional exchange of energy and materials influences the functioning and distribution of organisms. Biosphere - All of the areas where organisms can be found on or around earth. Geosphere Atmosphere Hydrosphere Made up of all of the ecosystems and landscapes If a logging project starts at one end of a river, how may the runoff effect the whole river, ecosystems far down stream, and the ocean at the end of the river?

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23 Introduction to Ecology and the Biosphere 52.1: Biological Research and Environmental Decisions

24 Biological Research and Environmental Decisions Ecology at its core is a basic (discovery) science Basic science science for the sake of learning An evolution of Natural History The observation of organisms in nature and the systematic recording of these findings. Modern ecology includes observation and experimentation. Use of experimental design and statistical inferences made from forming hypotheses, manipulating variables in the environment and observing the outcome. 24

25 Ecology and Evolutionary Biology Evolution The process of organisms adapting to their environment over many generation through the process of natural selection. This time frame is known as evolutionary time Natural Selection Differential survival and reproduction among individuals due to environmental selection pressures Survival of the fittest This time frame is known as ecological time Minute to minute interactions between organisms and the environment 25

26 Interactions: Go hand in hand short-term (ecological time) interactions of organisms with their environments could have long term (evolutionary time) effects through natural selection.

27 Interactions: Ecological time Behavior Learning Acclimatization Evolutionary time Adaptation

28 Ecology and Environmental Issues Ecology Science Provides evidence and scientific understanding (reasoning) needed to help conserve and sustain life. Environmentalism Advocating for the protection of nature Important to make distinction between science and advocacy!!! Ecologists educate legislature and the public how society uses this knowledge is beyond the realm of science. 28

29 Ecology and Environmental Issues Rachel Carson The original environmentalist! Wrote Silent Spring 1962 Recognized the network of connections among species. Sparked modern environmental movement The control of nature is a phrase conceived in arrogance, born of the Neanderthal age of biology and philosophy, when it was supposed that nature exists for the convenience of man. 29

30 Introduction to Ecology and the Biosphere 52.2: Interactions between organisms and the environment limit the distribution of species

31 Interactions between organisms and the environment limit the distribution of species 31