Ecology and Taxonomy

Overview of Biotic and Abiotic Factors

• Biotic Factors:

  • Defined as the living components of an ecosystem.

  • Examples include plants, animals, bacteria.

• Abiotic Factors:

  • Defined as the nonliving components of an ecosystem.

  • Examples include sunlight, soil, rocks, and water.

Ecosystems and Their Components

• Ecosystem Definition:

  • A community of living organisms interacting with each other and their abiotic environment.

  • Includes all living beings (e.g., animals, plants) and nonliving factors (e.g., temperature, water).

• Levels of Organization:

  • Individual: A single organism.

  • Population: A group of individuals of the same species.

  • Community: Different populations of various species interacting.

  • Ecosystem: Community plus abiotic factors.

  • Biome: A larger geographical area defined by climate, vegetation, and animal communities.

  • Biosphere: The global ecological system integrating all ecosystems.

Roles Within Ecosystems

• Niche:

  • Refers to the role or function of an organism within its ecosystem, including its interactions for resources, habitat, and position in food webs.

  • For example, a bunny's role may be as a prey, while a deer also serves as prey but at a different ecological level.

Competition in Communities

• Interspecific Competition:

  • Competition between different species.

• Intraspecific Competition:

  • Competition among individuals of the same species.

• Niches are crucial in understanding competition, as overlapping niches can lead to competition for resources.

Limiting Factors

• Biotic Limiting Factors:

  • Examples include competition, predation, and parasitism.

• Abiotic Limiting Factors:

  • Examples include availability of water, temperature, and nutrient levels in soil.

Predator-Prey Relationships

• The predator-prey cycle presents a balance where increases in prey lead to increases in predators, and vice versa. This creates oscillating population dynamics:

  • More prey leads to more predators.

  • Peak predator populations result in lowered prey populations, allowing the prey to recover.

• Changes in this cycle can also be influenced by abiotic factors.

Human Impact on Ecosystems

• Human Factors:

  • Activities such as deforestation, agriculture, and carbon emissions significantly affect populations and ecosystems.

  • Fracking: A controversial method of extracting fossil fuels that can cause environmental disturbances.

Taxonomy Overview

• Taxonomy:

  • The scientific classification system of living organisms.

  • Organisms are classified into three domains:

  • Archaea: Single-celled organisms, often extremophiles.

  • Bacteria: Another group of single-celled organisms without a nucleus.

  • Eukarya: Multicellular or single-celled organisms that have a nucleus (includes animals, plants, fungi).

• Levels of Taxonomic Classification:

  • From broadest to most specific: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

  • Example: Humans are classified as (\text{Homo sapiens}).

Binomial Nomenclature

• Definition:

  • A system using two names to uniquely identify species: the first name is the genus and the second is the species.

• Formula:

  • Genus name capitalized, species name in lowercase (e.g., (\text{Ursus arctos}) for brown bears).

• This system ensures clarity and precision in naming organisms, standardizing biological classification across sciences.

  Taxonomy Domain