Ecology in the Anthropocene

Ecology in the Anthropocene

• Ecology studies interactions between organisms and their environment, determining their distribution and abundance.
• The Anthropocene is the current geological epoch marked by significant human impact.
• The Great Acceleration refers to the intense increase in planetary metrics due to human activities.
• Anthropogenic effects encompass human-caused ecological impacts like deforestation and ocean acidification.
• Multiple hypothesis testing involves using ecological data to test hypotheses for the best explanation.
• Ecological modeling helps comprehend ecological patterns and predict ecosystem responses to changes.

Levels of Biological Organization

• Biological organization increases in complexity from individuals to the biosphere:
  • Individuals < Populations < Communities < Ecosystems < Landscapes < Biomes < Biosphere.

Ecologists' Actions

• Ecologists observe and document natural history.
• Experimental ecology and null hypothesis testing are used.
• Multiple hypothesis testing compares different explanations.
• Ecological modeling is conducted.

Key Concepts in Ecology

• Ecology examines organism interactions and their effects on natural systems.
• Anthropogenic effects are now central to ecology, focusing on conservation, management, and restoration.
• Naturalists collect environment data through observations and research.
• Experimental ecology uses experiments and null hypothesis testing for ecological questions.
• A null hypothesis is a statement of no change.
• An alternative hypothesis indicates directional change a scientist aims to prove.
• Multiple hypothesis testing assesses various hypotheses using ecological data.
• Ecological modeling clarifies ecological patterns and forecasts ecosystem responses, establishing core principles in ecology.

Quantitative Reasoning in Ecology

• It involves applying mathematical thinking to measured data for a deeper understanding.
• Models help understand ecological mechanisms and predict ecological systems responses.
• Conceptual models display relationships between system components by identifying problems, including aspects, and diagrams.
• Mathematical models translate conceptual models into mathematical terms, using equations and data.
• Iteration refines models.
• A variable, changeable value in an equation, is of interest.
• A parameter is an element unaffected in a model.
• Deterministic models produce consistent results with consistent initial values.
• Stochastic models include random variation in parameters of the model.
• Quantitative reasoning uses metrics to understand a topic and collect data for analysis.
• Models mimic patterns, abstract reality, and rely on math.
• Conceptual models offer a theoretical view on interacting components; using questions, important aspects, and diagrams.
• Mathematical models translate models using birth, death, immigration factors; models are improved via iteration.
• Categorical data uses non-numerical categories.
• Numerical data uses inherent numerical values, including continuous (any real value) and discrete (counts only as integers) variables.
• Population: A large group under study.
• Sample: population subset used to characterize the group.
• Data includes generalization, quantification, and exposes relationships.
• Response variables (dependent) are affected in explanatory variables (independent), and frequency distributions use graphs/counts.

Global Climate and Biomes

• The biosphere includes all living organisms and their environments (hydrosphere, atmosphere, geosphere).
• Climate is the expected physical factor pattern (precipitation, heat, wind), while weather is the daily variation.
• Solar radiation is focused near the equator, varying seasonally.
• Atmospheric circulation involves air currents affecting climate and precipitation.
• The Coriolis effect, caused by Earth's rotation, influences air and water movement.
• Rain shadows occur when mountains block rainfall.
• Continental effects are related to climate variability due to the ocean's heat capacity.
• Transpiration, water exchange by plants, increases humidity.
• Terrestrial biomes are defined by water, sunlight, temperature, and soil.
• Terrestrial biomes include rainforest, desert, grassland, and forest types.
• Aquatic biomes are defined by light, nutrition, temperature, salinity, benthic structure.
• Aquatic biomes include estuaries, coral reefs, and the open ocean.
• Climate is the world's expected physical factor, and weather is the variations observed from day to day.
• Seasonal solar radiation leads to precipitation differences, as well as Coriolis effects.

Solar Radiation and Biomes

• At higher latitudes, solar radiation is slanting and diffuse resulting also in differences in precipitation.
• At low latitudes rays are concentrated.
• Tropical rainforests are near the equator, are warm, have high precipitation, and high biodiversity.
• Tropical dry rainforests are in areas like South America, have ~79 in of precipitation yearly, support frogs/flowers/ orangutans, and account for 8% of Earth's surface.
• Tropical Savannahs occur at 10-25° latitude N/S, have rainfall in 3-6 months and are warm/hot year-round.
• Deserts' latitudes are ±30° N/S, types in subtropical regions, have less than 25 cm of precipitation, scarcity can result in exposed features, biodiversity, and densities that are low.
• Mediterranean Scrubland is near oceans at 30-45° latitude, with hot/dry summers; cool/wet winters with precipitation of of 36-89 cm annually.
• Temperate Grasslands consist of vegetation with small scrubs at ±30-55° N/S; thunderstorms result in frequent fires.
• Temperate Forests, between ±35-60° degrees latitude, precipitation is always fluctuating, summers are warm, humid and in winter cold.
• Boreal Forests have permafrost and have precipitation that's constant.
• Tundra's temperatures average at ±14-3 F at >65° N/S latitude, and permafrost underlies.
• Oceans and water cover covers a total of 70% of the Earth, Estuaries see varying precipitation.

Evolution and Speciation

• Adaptations improve survival and reproduction.
• Carl Linnaeus grouped organisms by physical traits and defined genus and species in the 1700s.
• Binomial nomenclature classifies organisms by: Domain, Kingdom, Phylum, Class, Order, Family, Genus, and Species.
• The Morphological species concept defines species by physical and behavioral traits.
• The Biological species concept defines a species as interbreeding individuals with viable, fertile offspring and was developed by Ernst Mayr in 1942.
• Evolution is a shift in allele frequencies throughout a population over time.
• Natural selection favors survival and reproduction based on biotic and abiotic factors.
• Speciation creates new species from a common ancestor.
• Genes are portions of chromosomes that encodes for molecules.
• Alleles offer variations in genes.
• Gene flow moves alleles between populations.
• Genetic mutations occur when errors occur in DNA replication.
• Genetic drift describes haphazard events taking genes out of population.
• Mutation and gene flow add alleles to a population, while genetic drift and natural selection remove alleles.
• Evolutionary mechanisms include gene flow via dispersal/migration, genetic drift in populations which are small, and natural selection which factors in biotic/abiotic interactions.
• Biologists study species to define concepts/patterns such as predation, competition, and ecosystem function.
• Canis lupus (Wolf) is named using binomial classificiation with the inclusion of genus and species. Evolution can act on a faster predator.
• Speciation sees reproductive incompatibilities within a population.
• Natural Selection is the driver of evolution, with Charles Darwin defining genetic differences that determine the ability to reproduce adaptively.
• The process defines "evolutionary mechanisms" that leads to mutations.

Physiology and Behavior

• Species physiology and behavior involve trade-offs because resources like energy and time are limited so efficient optimization increases chances to survivie & reproduce .
• Organisms derive energy through consumation or photosynthesis to allocates essential processes
• The principle of energy allocation balances processes.
• Metabolic reactions require enzymes (with certain temp/ranges that when destroyed result in dysfunction).
• Poikilotherms have no thermal regulation, while ectotherms see regulation via actions and endotherms regulate inner factors.
• Homeotherms (birds, mammals) utilize heat to maintain range, and nonhomeotherms are slight (and non-metabolic in said regulation).
• Plants regulate processes through growth.
• Fine white hairs on plants allows for reflection of sunlight which defines how the trade-off includes energy allocation in plants as well as time.
• In a niche the conditions an organism can survive in have to align along with said species' effect to it's environment to be able to persist.
• The Niche defines conditions in which can have traits or behaviors that allow persistence in environments.
• Niches also have "fundamental" (abiotic factors), "realized" (biotic interactions), as well as ND hyper volume (disease factors).