Clarification Statement - S.HS.LS.2.1.CS:
Emphasis is on quantitative analysis and comparison of the relationships among interdependent factors including boundaries, resources, climate, and competition. Examples of mathematical comparisons could include graphs, charts, histograms, and population

Assessment Boundary - S.HS.LS.2.1.AB:
Assessment does not include deriving mathematical equations to make comparisons.

Science and Engineering Practices - 9-12.SEP5.2:
Use mathematical representations of phenomena to describe explanations.

Disciplinary Core Ideas - S.HS.LS.2.1.DCI:
LS2.A: Interdependent Relationships in Ecosystems •Ecosystems have carrying capacities, which are limits tothe numbers of organisms and populations they can support. Organisms would have the capacity to produce populations of great size were it not for the fact that environments and resources are finite. This fundamental tension affects the abundance (number of individuals) of species in any given ecosystem. •(NYSED) Carrying capacity results from the availability of biotic and abiotic factors and from challenges such as predation, competition, and disease.

Crosscutting Concepts - CC7.7:
The significance of a phenomenon is dependent on the scale, proportion, and quantity at which it occurs.

Clarification Statement - S.HS.LS.2.2.CS:
Examples of mathematical representations include finding the average, determining trends, and using graphical comparisons of multiple sets of data.

Assessment Boundary - S.HS.LS.2.2.AB:
Assessment is limited to provided data.

Science and Engineering Practices - 9-12.SEP5.5:
Use mathematical representations of phenomena or design solutions to support and revise explanations.

Disciplinary Core Ideas - S.HS.LS.2.2.DCI:
LS2.A: Interdependent Relationships in Ecosystems •Ecosystems have carrying capacities, which are limits tothe numbers of organisms and populations they can support. Organisms would have the capacity to produce populations of great size were it not for the fact that environments and resources are finite. This fundamental tension affects the abundance (number of individuals) of species in any given ecosystem. •(NYSED) Carrying capacity results from the availability of biotic and abiotic factors and from challenges such as predation, competition, and disease. LS2.C: Ecosystem Dynamics, Functioning, and Resilience •A complex set of interactions within an ecosystem can keep its numbers and types of organisms relatively constant over long periods of time under stable conditions. If a modest biological or physical disturbance to an ecosystem occurs, it may return to its more or less original status (i.e., the ecosystem is resilient), as opposed to becoming a very different ecosystem. Extreme fluctuations in conditions or the size of any population, however, can challenge the functioning of ecosystems in terms of resources and habitat availability.

Crosscutting Concepts - CC7.8:
Using the concept of orders of magnitudeallows one to understand how a model at one scale relates to a model at another scale.

Clarification Statement - S.HS.LS.2.6.CS:
Examples of changes in ecosystem conditions could include modest biological or physical changes, such as moderate hunting or a seasonal flood; and extreme changes, such as volcanic eruption or sea level rise.

Science and Engineering Practices - 9-12.SEP7.1:
Evaluate the claims, evidence, and reasoning behind currently accepted explanations or solutions to determine the merits of arguments.

Disciplinary Core Ideas - S.HS.LS.2.6.DCI:
LS2.C: Ecosystem Dynamics, Functioning, and Resilience •A complex set of interactions within an ecosystem can keep its numbers and types of organisms relatively constant over long periods of time under stable conditions. If a modest biological or physical disturbance to an ecosystem occurs, it may return to its more or less original status (i.e., the ecosystem is resilient), as opposed to becoming a very different ecosystem. Extreme fluctuations in conditions or the size of any population, however, can challenge the functioning of ecosystems in terms of resources and habitat availability.

Crosscutting Concepts - CC6.6:
Much of science deals with constructing explanations of how things change and how they remain stable.

Clarification Statement - S.HS.LS.2.7.CS:
Examples of human activities can include urbanization, building dams, and dissemination of invasive species. Examples of solutions could include simulations, product development, technological innovations, and/or legislation.

Science and Engineering Practices - 9-12.SEP5.6:
Create or revise a simulation of a phenomenon, designed device, process, or system.

Science and Engineering Practices - 9-12.SEP6.4:
Design, evaluate, and/or refine a solution to a complex real-world problem, based on scientific knowledge, student-generated sources of evidence, prioritized criteria, and tradeoff considerations.

Disciplinary Core Ideas - S.HS.LS.2.7.DCI:
LS2.C: Ecosystem Dynamics, Functioning, and Resilience •Moreover, anthropogenic changes (induced by human activity) in the environment—including habitat destruction, pollution, introduction of invasive species, overexploitation, and climate change—can disrupt an ecosystem and threaten the survival of some species. LS4.D: Biodiversity and Humans •Biodiversity is increased by the formation of new species (speciation) and decreased by the loss of species (extinction). (secondary to HS-LS2-7) •Humans depend on the living world for the resources and other benefits provided by biodiversity. But human activity is also having adverse impacts on biodiversity through overpopulation, overexploitation, habitat destruction, pollution, introduction of invasive species, and climate change. Thus sustaining biodiversity so that ecosystem functioning and productivity are maintained is essential to supporting and enhancing life on Earth. Sustaining biodiversity also aids humanity by preserving landscapes of recreational or inspirational value. (secondary to HS-LS2-7) ETS1.B: Developing Possible Solutions •When evaluating solutions, it is important to take intoaccount a range of constraints, including cost, safety, reliability, and aesthetics, and to consider social, cultural, and environmental impacts. (secondary to HS-LS2-7)

Crosscutting Concepts - CC2.8:
Empirical evidence is required to differentiate between cause and correlation and make claims about specific causes and effects.

Crosscutting Concepts - CC6.6:
Much of science deals with constructing explanations of how things change and how they remain stable.

Clarification Statement - S.HS.LS.2.8.CS:
Emphasis is on: (1) distinguishing between group and individual behavior, (2) identifying evidence supporting the outcomes of group behavior, and (3) developing logical and reasonable arguments based on evidence. Examples of group behaviors could include

Science and Engineering Practices - 9-12.SEP7.2:
Evaluate the evidence behind currently accepted explanations or solutions to determine the merits of arguments.

Disciplinary Core Ideas - S.HS.LS.2.8.DCI:
LS2.D: Social Interactions and Group Behavior •Group behavior has evolved because membership can increase the chances of survival for individuals and their genetic relatives. (HS-LS2-8)

Crosscutting Concepts - CC2.8:
Empirical evidence is required to differentiate between cause and correlation and make claims about specific causes and effects.