Topic 4.1: Species, communities and ecosytems
Essential Idea:
- The continued survival of living organisms, including humans, depends on sustainable communities.
Scales of interaction (individual, population, community)
Lesson summary:
4.1.U1 Species are groups of organisms that can potentially interbreed to produce fertile offspring.
4.1.U2 Members of a species may be reproductively isolated in separate populations.
4.1.U3 Species have either an autotrophic or heterotrophic method of nutrition (a few species have both methods).
4.1.U4 Consumers are heterotrophs that feed on living organisms by ingestion.
4.1.U5 Detritivores are heterotrophs that obtain organic nutrients from detritus by internal digestion.
4.1.U6 Saprotrophs are heterotrophs that obtain organic nutrients from dead organisms by external digestion.
4.1.U7 A community is formed by populations of different species living together and interacting with each other.
4.1.U8 A community forms an ecosystem by its interactions with the abiotic environment.
4.1.U9 Autotrophs obtain inorganic nutrients from the abiotic environment.
4.1.U10 The supply of inorganic nutrients is maintained by nutrient cycling.
4.1.U11 Ecosystems have the potential to be sustainable over long periods of time.
4.1.Skill 1 Classifying species as autotrophs, consumers, detritivores or saprotrophs from a knowledge of their mode of nutrition.
Lesson summary:
- Individual populations of one species interact with other populations in a community as well as with nonliving (abiotic) factors.
- NOS: Looking for patterns, trends and discrepancies: plants and algae are mostly autotrophic but some are not.
4.1.U1 Species are groups of organisms that can potentially interbreed to produce fertile offspring.
4.1.U2 Members of a species may be reproductively isolated in separate populations.
4.1.U3 Species have either an autotrophic or heterotrophic method of nutrition (a few species have both methods).
4.1.U4 Consumers are heterotrophs that feed on living organisms by ingestion.
4.1.U5 Detritivores are heterotrophs that obtain organic nutrients from detritus by internal digestion.
4.1.U6 Saprotrophs are heterotrophs that obtain organic nutrients from dead organisms by external digestion.
4.1.U7 A community is formed by populations of different species living together and interacting with each other.
4.1.U8 A community forms an ecosystem by its interactions with the abiotic environment.
4.1.U9 Autotrophs obtain inorganic nutrients from the abiotic environment.
4.1.U10 The supply of inorganic nutrients is maintained by nutrient cycling.
4.1.U11 Ecosystems have the potential to be sustainable over long periods of time.
4.1.Skill 1 Classifying species as autotrophs, consumers, detritivores or saprotrophs from a knowledge of their mode of nutrition.
Investigation: designing model ecosystems
Lesson summary:
4.1Skill 2: Setting up a sealed mesocosm to try to establish sustainability.
Link: Mesocosms
Link: Mesocosms: Spivak Lab-Woods Hole
Video: Spivak Lab-Woods Hole
Lesson summary:
- Model systems allow variables to be manipulated in ways not possible in natural settings. A well designed mesocosm will become self-sustaining over time.
4.1Skill 2: Setting up a sealed mesocosm to try to establish sustainability.
Link: Mesocosms
Link: Mesocosms: Spivak Lab-Woods Hole
Video: Spivak Lab-Woods Hole
Application: Use of statistical analysis to explore ecosystems interactions.
Lesson summary:
4.1Skill 3: Testing for association between two species using the chi-squared teste with data obtained by quadrat sampling.
4.1Skill 4: Recognizing and interpreting statistical significance.
Lesson summary:
- Ecosystems can be examined in natural setting by applying carefully controlled sampling techniques and statistical analysis.
4.1Skill 3: Testing for association between two species using the chi-squared teste with data obtained by quadrat sampling.
4.1Skill 4: Recognizing and interpreting statistical significance.