introduction to ecology

Ecology definition

the study of the relationships between organisms and each other, and between organisms and their environment

different types of specialties in ecology and locations

community, freshwater, disease, behavioral, etc.

-field work, lab, and theoretical

levels of ecology

individual, population, community, ecosystem, landscape, biosphere

definition of an individual

• single organism (a zebra)

• common subdiscipline: psychological + behavioral

definition of a population

• a group of individuals of the same species/taxon that live together (a herd of zebras)

• can be large scale (population of zebra in the world) or smaller scale (population of zebra in Kenya)

• common subdiscipline: population

definition of community

• a group of multiple species living in the same habitat (lion + zebra)

• common subdiscipline: community

definition of ecosystem

• entire biological community with its species (biotic) plus physical and chemical (abiotic) environment (how does fire affect food availability in grassland ecosystems)

definition of landscape

• group of interconnected ecosystems

definition of biosphere

• global biological environment (what role does concentration of atmospheric CO2 play in the regulation of global temp)

• common subdiscipline: globus

what basis do ecologists design their study based on

• temporal and spatial scale of research (lake vs. creek)

• research questions

• available research tools

three categories of research

• observational studies (field and lab): w/o collecting data, descriptive/hypothesis testing

• experimental studies (field and lab): changes the variables of interest, hypothesis/predictions

• theoretical modeling (theory): describe ecological phenomena, descriptive/hypothesis testing/ hypothesis generating

MacArthur warbler study (1958)

• how did warbler species with the same ecological requirements (food and habitat) co-exist

• observed: lived in spruce trees, niches could be slightly different

• findings: different species fed on different sections of the tree

Nadkarni rainforest studies (1981-1984)

• how are rainforest trees getting their nutrients when the soil is nutrient-poor

• observed: took inventory of rainforest plants + nutrients

• findings: epiphytes were providing nutrients to trees through nutrient mats

Whitaker Butterfly study (2019)

• do butterfly larvae eat ants or ant regurgitations on acacia trees

• stable isotope analysis was used to measure ratios in the body

• findings: butterfly larvae are herbivorous, feed off the tree and not the ants

Galen bumblebee wildflower study (1989)

• do bees contribute to the evolution of larger flowers in alpine sky pilot plants

• flower size vs. seed # in bee pollinated plants vs. no bees

• bigger flower = more seeds

• findings: bigger flowers = more seeds ONLY in bee pollinated plants

Galen bee activity in light vs. darkness (2019)

• does bee activity differ in light vs. darkness

• used solar eclipse for a natural experiment

• community science: recorded bee buzzing during eclipse

• findings: bee activity increased with light intensity increasing

types of models

conceptual: primarily pictures and diagrams

quantitative: primarily mathematical (lots of equations and simulations)

applications of ecology

• ecological research can inform law and policy

• CITES: Convention for International Trade in Endangered Species of Flora and Fauna

• ESA: U.S Endangered Species Act

• both provide protections to endangered and threatened species

case of the snail darter

• Percina tanasi

• original range: only in the little TN River, endangered in 1975

• TVA wanted to build a man that would destroy the habitat

Darter vs. Dam

• TVA vs. Hill, U.S supreme court ruled in favor of the Darter (1978)