lesson 2

• Ecology studies the connections between living organisms, including humans, and their environment
• Ecology focuses on the vital connections between plants and animals and their surroundings
• Species are groups of living organisms that are broadly similar and can breed with each other
• Populations consist of individuals of the same species living together within a given area, interbreeding and competing for resources
• A community is a group of different species living in the same area, a natural grouping of plants and animals within a habitat
• An ecosystem includes all organisms in an area plus the nonliving parts of their environment
• Biomes are areas recognized by the distinctive life forms of their dominant species, often by the dominant type of vegetation
• The biosphere is the portion of Earth where life occurs, extending several km up in the atmosphere to the deepest parts of the oceans
• Ecosystems are communities of living and nonliving organisms linked together through energy collection and use
• Natural ecosystems are dependent on solar radiation, e.g., forests, grasslands, oceans, lakes, rivers, and deserts
• Manmade ecosystems are dependent on solar energy, e.g., agricultural fields and aquaculture ponds
• Ecosystem services sustain and fulfill human life, providing benefits like food, clean water, disease regulation, climate control, and cultural and spiritual benefits
• Provisioning services include benefits like food, water, timber, fuel, and medicinal resources extracted from nature
• Regulating services moderate natural phenomena like pollination, decomposition, water purification, erosion control, carbon storage, and climate regulation
• Cultural services contribute to people's development and advancement, involving ecosystems, knowledge building, creativity, and recreation
• Supporting services like photosynthesis, nutrient cycling, soil creation, and the water cycle are crucial for ecosystem sustainability
• Components of ecosystems include trophic levels, with producers using sunlight or chemical energy to make food
• Consumers rely on other organisms for energy and food supply, with primary consumers mainly depending on plants, secondary consumers eating other animals, and tertiary consumers eating other carnivores
• Scavengers feed on dead animals, while decomposers break down dead and decaying material
• Physical structures of ecosystems include vertical stratification, horizontal stratification, edges, and ecotones
• Biological structures involve species dominance, species diversity, and species abundance within a community
• Conservation aims to make human-environment relationships sustainable while extracting natural resources, while preservation involves setting aside areas free of human influence
• Flagship species act as ambassadors or symbols for habitats, issues, campaigns, or environmental causes
• Priority species reflect key threats in an ecoregion, crucial for conservation and the wellbeing of local populations
• Keystone species play essential roles in the structure, functioning, or productivity of a habitat or ecosystem
• Indicator species are chosen as proxies for the state of an ecosystem or a specific process within it
• Food chains transfer energy and material through a series of organisms, while food webs comprise complex feeding relationships
• Trophic levels refer to feeding levels in an ecosystem, with energy pyramids showing the relative energy available at each level
• Biomass pyramids represent the total living biomass at different trophic levels in an ecosystem
• Biogeochemical cycles involve the cycling of materials between the environment and organisms through processes like the water cycle, nitrogen cycle, phosphorus cycle, and carbon cycle
• Ecological succession is a series of changes in an ecological community over time
• Ecological interactions between organisms include competition, predation, symbiosis (mutualism, commensalism, parasitism), and niche differentiation
• The competitive exclusion principle states that two different species cannot occupy the same niche in the same place for long