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Announcements. Assignment for discussion section read Bradshaw and Bekoff paper come to section prepared to discuss questions Change in Kevin’s office hours Check out the website: www.es.ucsb.edu/classes/envs100/. Summary. What is Ecology? Ecology vs. Environmentalism
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Announcements • Assignment for discussion section • read Bradshaw and Bekoff paper • come to section prepared to discuss questions • Change in Kevin’s office hours • Check out the website: www.es.ucsb.edu/classes/envs100/
Summary • What is Ecology? • Ecology vs. Environmentalism • Observation and Experimentation • The Scientific Method • Roots of Ecology • Theory of Evolution by Natural Selection
Two-minute quiz: Ecology is (pick the best answer): • the study of the distribution of plant and animal species across the earth • the same as environmental science • the study of how abiotic factors determine the evolution of animals and plants • a method for classifying organisms • a relatively old science • the study of the relationships of living things to one another and their environment
Theory of Evolution by Natural Selection • lineages with the most appropriate biological programming (genes) for the current conditions will leave the most descendants • what is a lineage? • family group • coming from a common ancestor
Defining ‘evolution’ • Scientific definition vs. common usage
Defining ‘evolution’ Scientific Definitions: • All the changes that have transformed life on earth from its earliest beginnings to the diversity that characterizes it today –Neil Campbell
Defining ‘evolution’ Scientific Definitions: • All the changes that have transformed life on earth from its earliest beginnings to the diversity that characterizes it today –Neil Campbell • The origination of species of animals and plants … –O.E.D.
Defining ‘evolution’ Scientific Definitions: • All the changes that have transformed life on earth from its earliest beginnings to the diversity that characterizes it today –Neil Campbell • The origination of species of animals and plants … –O.E.D. From a scientific point of view, evolution is just how new species come about …and evolution does not mean “getting better”
Defining ‘evolution’ Scientific Definitions: • All the changes that have transformed life on earth from its earliest beginnings to the diversity that characterizes it today –Neil Campbell • The origination of species of animals and plants… –O.E.D. Common Usage: • A process of continuous change from a lower, simpler, or worse to a higher, more complex, or better state –Merriam-Webster’s Dictionary
Humans and evolution • Where does the “getting better” idea come from? • view of humans as an evolutionary endpoint
Humans and evolution • Where does the “getting better” idea come from? • view of humans as an evolutionary endpoint • Humans and natural selection • humans are different • the “unfit” often live to reproduce • strong culture • direct contact with nature is limited • ubiquitous presence
Where does ecology fit in? • Ecology is an interdisciplinary science • Ecological studies are done at the interface of these 3 fields
Organization within Ecology Ecosystem Ecology Community Ecology Population Ecology Behavioral Ecology Physiological Ecology
Ecology subfields: • Physiological Ecology: • the study of the diverse adaptations that enable organisms to function in their environment
Behavioral Ecology: the study of the ecological and evolutionary basis for animal behavior the roles of behavior in enabling animals to adapt to their ecological niches Mimic Octopus Video Clip Ecology subfields:
Ecology subfields: • Behavioral Ecology: • the study of the ecological and evolutionary basis for animal behavior • the roles of behavior in enabling animals to adapt to their ecological niches • does “plant behavior” exist? • Mimic Octopus Video Clip
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart • nervous and endocrine systems are often at work in animals
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart • nervous and endocrine systems are often at work in animals • plants have hormones and signaling pathways but no “brain”
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart • nervous and endocrine systems are often at work in animals • plants have hormones and signaling pathways but no “brain” • plants respond to stimuli such as light, gravity, and touch
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart • nervous and endocrine systems are often at work in animals • plants have hormones and signaling pathways but no “brain” • plants respond to stimuli such as light, gravity, and touch • sometimes the responses are very slow
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart • nervous and endocrine systems are often at work in animals • plants have hormones and signaling pathways but no “brain” • plants respond to stimuli such as light, gravity, and touch • sometimes the responses are very slow • plants in motion
Plant behavior • behavior is defined as “an observable response to environmental stimuli” –Starr and Taggart • nervous and endocrine systems are often at work in animals • plants have hormones and signaling pathways but no “brain” • plants respond to stimuli such as light, gravity, and touch • sometimes the responses are very slow • plants in motion • very few people study the “why’s”
Ecology subfields: • Population Ecology: • the study of individuals of a certain species occupying a defined area during a specific time
Ecology subfields: • Community Ecology: • the study of how populations of organisms interact
Ecology subfields: • Ecosystem Ecology: • the study of interactions between organisms and their environment as an integrated system
Different types of ecologists ask different types of questions.
ScaleQuestion How does carbon loss from plowed soils influence global climate? Global ecosystem How does deforestation influence the water supply to nearby towns? Watershed Forest ecosystem How does acid rain influence forest productivity? Endolithic ecosystem What are the biological controls over rock weathering?
Temporal Scale • Length of time • Type of process is important: • many ecological processes take decades • unfortunately funding usually lasts for only 3 years • LTER • biology can be nearly instantaneous • geological processes are very slow • chemistry can be fast or slow • enzymatic activity • lifetime of certain gases in the atmosphere
Spatial Scale • “Powers of Ten” Online Demo
Summary for today… • Definition of ‘lineage’ and ‘evolution’ • Humans and evolution • Ecology as an interdisciplinary science • Different subfields in Ecology: • Physiological Ecology • Behavioral Ecology • Population Ecology • Community Ecology • Ecosystem Ecology • Temporal and Spatial scale in ecology
Announcements • Handouts • I have more copies • You can also get them online: www.es.ucsb.edu/classes/envs100/ • My office hours: Mondays 10:15-12:00pm • Panel on careers in the environment? • Fish and Wildlife/Fish and Game • Non-governmental organizations • Consulting firms and private companies • Education
From Monday… • Scientific vs. common use of the word “evolution” • Subfields of Ecology • Scale
Two-minute quiz… • Imagine that you are an ecosystem ecologist. You travel to rural Costa Rica, where several of the people you meet work on banana plantations. You visit a plantation, and then decide to incorporate a study of one into your research program. Which one of the following questions might you pursue as part of your research?
How does the fruit-eating bat population respond after a banana plantation is abandoned? • How many different species of ant live in a banana plantation, and how does this number compare with an equally-sized patch of rainforest? • How much nitrogen enters streams from a banana plantation in comparison to old growth rainforest? • How complex are the insect-based food webs in a pesticide-free banana plantation? • Which contains foliage that is more difficult to consume, a banana plant or a walking palm?
What is an ecosystem? • All the organisms and the abiotic entities with which they interact within a given space • The space is delineated by the person studying it • Can be as large as the whole earth • Can be as small as a test tube • What determines the appropriate scale?
What is an ecosystem process? • Transfer of materials or energy from one pool to another • Can involve biotic and abiotic components of the system
What regulates the function of ecosystems? • Feedback mechanisms • Energy flow
Positive feedback Negative feedback B B A A Feedback mechanisms
Ice reflects the sun’s rays With less ice, the darker surface of land and ocean absorb more heat Positive feedback • Can push system to a new state warming
Positive feedback • Can push system to a new state Fertile soil Rich litter Fast decomposition Rapid nutrient release
Negative feedback • Tends to keep a system stable Prey Predator
Energy Flow • Climate: • transport of energy through the earth system • key control over distribution of earth’s ecosystems • Biology: • controls the transfer of energy within and between organisms
The sun Geothermal activity Where does energy come from?
What happens to energy from the sun? Reflected by clouds and atmosphere 23 albedo 100 Reflected by surface 8 Absorbed by atmosphere and clouds 57 20 2 47 Absorbed in photosynthesis Absorbed as heat
Energy Budget • Albedo: depends on reflectivity • Water: 2% • Snow: 50-90% • Clouds: 90% • Vegetation: 5-30% • Photosynthesis: 2% chemical energy • Heat: the rest (8-90%) drives climate
Weather describes short term variability Difficult to predict Weather vs. Climate
Link to “butterfly effect” online demo The Butterfly Effect "sensitive dependence upon initial conditions"
Weather, chaos, and the butterfly effect • Meteorologist Edward Lorenz, a pioneer of chaos theory, coined the famous phrase “the butterfly effect”. • The work of weather, he argued, can ultimately magnify the flapping of a butterfly’s wings into a typhoon. • The phrase has become shorthand for the way tiny factors working through complex systems can work huge changes in history. • 'Chaotic' motion is not completely random. Although precise details of the motion cannot be predicted, patterns can be seen in the chaos.