Notes 1: What is Ecology?
• Ecology Definition
o The study of interactions of organisms with one another and the environment
o These interactions determine if the organism can survive or not
§ Determine distribution and abundance of organisms
o Scientific study of distribution and abundance of organisms and interactions with
environment
§ Through space and time
• Space = where they live at a given time
• Time = when in the ecological development of a community they
live
§ Red-throated and Rufous hummingbirds
• Lower metabolism when temperatures drop
• Expend less energy but still stay warm
• Lower body temperature than the day (warmer temperatures)
o Primary science
§ Like cell biology, genetics, physiology
§ General knowledge
§ Applications to applied sciences
• Sustainability, conservation biology
• Ex: human physiology is a basic science, medicine is an applied
science
§ Exchange of energy between all earth systems
• What it is not
o Not directly an applied science
o Not sustainability
o Not curing planetary problems
o No social or political agenda
§ Just the truth of the universe
o Not philosophy
§ That is deep ecology
• The Challenge
o Diversity of living things
o Cell complexity
o Conclusions from one system may not apply to others
§ So ecology is like an accumulation of stories with few general principles
§ Difficult to study
o Dynamic interactions
§ Developmental changes in individuals
• Like tadpole to frog
§ Change in abundance, birth/death rate, genetic structure of population
• As population size changes
§ Succession: changes in community composition over time
, • Age of habitat
§ Evolutionary changes over geologic time
• “Can’t step in same river twice” because the river is (or other
forms of nature are) constantly changing
• Approaches in Ecology
o Biological Organization
§ Organism
• Exchange of energy and materials with environment
• Survival and reproduction
• Unit of natural selection
• Observable behavior
• Individuals interact by
o Harvesting energy
o Excreting waste
o Tolerating abiotic conditions
o Physiological, morphological, behavioral responses to
environments
§ Population
• Population dynamics
• Unit of evolution
• Distribution in space, time, demography, genetic, rate of
birth/death
• Evolved adaptations to environments
o Genetic changes
o Interactions between organisms within population
§ Mating
§ Territorial behavior
§ Reproductive fitness
§ Community
• Interactions among populations
o Diversity
o Predation
o Competition
o Mutualism
o How interactions affect number of individuals in
populations
• Unit of biodiversity
§ Ecosystem
• Energy flux
o Through community
o Between community and non-living sub-systems
§ Atmosphere
§ Hydrosphere
, § Lithosphere/soil
• Nutrient cycling
§ Biosphere
• Global processes
• Totality of life
• Effects on energy balance and flux through Earth systems
o Atmosphere
o Lithosphere
o Biological Scales
§ Ecologists usually focus on one level of biological organization
§ How interactions and dynamics at one level affect another
§ Each level has emergent properties
• Only expressed at that level, not lower levels
o Ex: population density but no organism density
• Going the opposite way is reductionism
o Describing the sub-systems of a complex system with the
understanding that knowing the sub-system allows one to
understand the whole system
§ Ex: structurally, look at a dead human body to
understand the function of a living human body
§ Structure and function
o Not always perfect
§ In genetics, cannot describe everything about an
organism just by genes
§ 98% similarity of human and chimpanzee genes,
but the organisms as a whole are not 98% similar
o Energy and Dynamic States
§ Laws of thermodynamics
• First law: energy and matter cannot be created nor destroyed
o Only converted to different forms
o To do work, energy and matter must be taken in
o Measure energy/matter flow with energy budgets (for
individuals)
• Second law: no chemical energy transformation is 100% efficient
o Some is lost as heat
o To do work, more energy and matter must be taken in
than will be used
§ Need some extra
o Energy is lost from individual energy budgets to trophic
food pyramids
§ Life is always processing energies
§ Dynamic equilibrium
• Seen as stasis
, o Like body size of individual, number of individuals in a
population, herbivore biomass
• Equilibrium between additive and subtractive processes
o Body mass: Food in – waste out
o Population size: (Births + immigrants) – (deaths +
emigrants)
o Herbivore biomass: Final – initial population size
§ Or final - initial individual growth rate
§ Herbivore biomass represents food available to
carnivores
o Ecological Roles
§ Involve flow of energy and matter
• And information from communication
• Between organisms, populations, communities, ecosystems in
biosphere
§
• Primary producers
o Fix energy in sunlight
o Build/absorb organic molecules
o Some bacteria, some protists, plants
o Gives energy to decomposers and consumers
o Gets energy from decomposers and consumers (for
carnivorous plants only)
• Consumers
• Ecology Definition
o The study of interactions of organisms with one another and the environment
o These interactions determine if the organism can survive or not
§ Determine distribution and abundance of organisms
o Scientific study of distribution and abundance of organisms and interactions with
environment
§ Through space and time
• Space = where they live at a given time
• Time = when in the ecological development of a community they
live
§ Red-throated and Rufous hummingbirds
• Lower metabolism when temperatures drop
• Expend less energy but still stay warm
• Lower body temperature than the day (warmer temperatures)
o Primary science
§ Like cell biology, genetics, physiology
§ General knowledge
§ Applications to applied sciences
• Sustainability, conservation biology
• Ex: human physiology is a basic science, medicine is an applied
science
§ Exchange of energy between all earth systems
• What it is not
o Not directly an applied science
o Not sustainability
o Not curing planetary problems
o No social or political agenda
§ Just the truth of the universe
o Not philosophy
§ That is deep ecology
• The Challenge
o Diversity of living things
o Cell complexity
o Conclusions from one system may not apply to others
§ So ecology is like an accumulation of stories with few general principles
§ Difficult to study
o Dynamic interactions
§ Developmental changes in individuals
• Like tadpole to frog
§ Change in abundance, birth/death rate, genetic structure of population
• As population size changes
§ Succession: changes in community composition over time
, • Age of habitat
§ Evolutionary changes over geologic time
• “Can’t step in same river twice” because the river is (or other
forms of nature are) constantly changing
• Approaches in Ecology
o Biological Organization
§ Organism
• Exchange of energy and materials with environment
• Survival and reproduction
• Unit of natural selection
• Observable behavior
• Individuals interact by
o Harvesting energy
o Excreting waste
o Tolerating abiotic conditions
o Physiological, morphological, behavioral responses to
environments
§ Population
• Population dynamics
• Unit of evolution
• Distribution in space, time, demography, genetic, rate of
birth/death
• Evolved adaptations to environments
o Genetic changes
o Interactions between organisms within population
§ Mating
§ Territorial behavior
§ Reproductive fitness
§ Community
• Interactions among populations
o Diversity
o Predation
o Competition
o Mutualism
o How interactions affect number of individuals in
populations
• Unit of biodiversity
§ Ecosystem
• Energy flux
o Through community
o Between community and non-living sub-systems
§ Atmosphere
§ Hydrosphere
, § Lithosphere/soil
• Nutrient cycling
§ Biosphere
• Global processes
• Totality of life
• Effects on energy balance and flux through Earth systems
o Atmosphere
o Lithosphere
o Biological Scales
§ Ecologists usually focus on one level of biological organization
§ How interactions and dynamics at one level affect another
§ Each level has emergent properties
• Only expressed at that level, not lower levels
o Ex: population density but no organism density
• Going the opposite way is reductionism
o Describing the sub-systems of a complex system with the
understanding that knowing the sub-system allows one to
understand the whole system
§ Ex: structurally, look at a dead human body to
understand the function of a living human body
§ Structure and function
o Not always perfect
§ In genetics, cannot describe everything about an
organism just by genes
§ 98% similarity of human and chimpanzee genes,
but the organisms as a whole are not 98% similar
o Energy and Dynamic States
§ Laws of thermodynamics
• First law: energy and matter cannot be created nor destroyed
o Only converted to different forms
o To do work, energy and matter must be taken in
o Measure energy/matter flow with energy budgets (for
individuals)
• Second law: no chemical energy transformation is 100% efficient
o Some is lost as heat
o To do work, more energy and matter must be taken in
than will be used
§ Need some extra
o Energy is lost from individual energy budgets to trophic
food pyramids
§ Life is always processing energies
§ Dynamic equilibrium
• Seen as stasis
, o Like body size of individual, number of individuals in a
population, herbivore biomass
• Equilibrium between additive and subtractive processes
o Body mass: Food in – waste out
o Population size: (Births + immigrants) – (deaths +
emigrants)
o Herbivore biomass: Final – initial population size
§ Or final - initial individual growth rate
§ Herbivore biomass represents food available to
carnivores
o Ecological Roles
§ Involve flow of energy and matter
• And information from communication
• Between organisms, populations, communities, ecosystems in
biosphere
§
• Primary producers
o Fix energy in sunlight
o Build/absorb organic molecules
o Some bacteria, some protists, plants
o Gives energy to decomposers and consumers
o Gets energy from decomposers and consumers (for
carnivorous plants only)
• Consumers
