B1 - Individuals, Populations, and Communities in Ecosystems PDF

B1 - Individuals, Populations, and Communities in Ecosystems I can… Define species, population, community and ecosystem and explain the interrelationships among them Pre-Assessment Indicate whether each statement is true or false. Rewrite a false statement to make it true. 1. Ecosystem...

B1 - Individuals, Populations, and Communities in Ecosystems I can… Define species, population, community and ecosystem and explain the interrelationships among them Pre-Assessment Indicate whether each statement is true or false. Rewrite a false statement to make it true. 1. Ecosystems with greater biodiversity tend to be fragile. 2. Natural ecosystems typically have greater biodiversity than artificial ecosystems. 3. Introducing exotic species into an ecosystem helps improve biodiversity and helps all organisms within an ecosystem. 4. An organism’s physical traits are affected by both its genetic makeup and the environment. 5. Virtually all large populations exhibit genetic variation among individuals. Organisms in Their Environment Environment: Everything that affects an organism, as well as everything that the organism affects Within environment: ○ Biotic: Living components ○ Abiotic: Non-living components Ecology: The study of ecosystems, communities, populations, and the biotic & abiotic factors that influence each Levels of Hierarchy Example In the ecosystem below, consider the following… At the ecosystem level: What biotic (living) and abiotic (nonliving) factors are at play? At the community level: How do populations of different species interact with one another? (e.g. predator/prey interactions, interspecific competition, symbiotic relationships, etc.) At the population level: Which factors affect the growth of each population? (e.g. food, habitat, and mate availability) At the organism level: Which adaptations does an individual possess that allows them to have a greater capacity for survival & reproduction compared to others of their species? Individual Organism At the level of the individual, ecologists often focus on learning about how the abiotic environment affects its behaviour and physical features (adaptations) Help to explain distribution of organisms Morphology: Physical characteristics of an organism that is affected by abiotic conditions Surface-dwelling fish in the Antarctic Ocean possess a number of unique adaptations which allow them to thrive in the cold water Species Species: Group of organisms that are able to breed with one another and produce fertile offspring ○ Ex. Humans, grizzly bears ○ Non-ex. Mules, ligers Populations Population: Group of individuals of same species living in a specific area at the same time Population ecologists focus on how a group of individuals of the same species changes in size and distribution over time. Populations may be impacted by: ○ Competition for resources ○ Changes in environment Each of these glacier lilies is part of a population. Communities Community: Populations of different species interacting with one another Ecologist who study communities look at interactions between many species and how these interactions affect populations Interactions include: ○ Competition between individuals of same species in different populations ○ Relationships between predator and prey populations Abiotic factors also influence how many species live in a community ○ Ex. Hours of sunlight, moisture available Ecosystem and Biosphere Ecosystem: All biotic and abiotic factors of environment The biosphere is the largest ecosystem ○ Includes all parts of Earth that are inhabitable by some type of life, including the abiotic components Populations aren’t randomly distributed throughout biosphere Collared pika populations have declined dramatically between 1990-2000. Likely ○ Distribution of species is related to ways due to rising global temperatures. biotic and abiotic components of the environment affect ability of species to survive