1 + Examining Cause and Effect Aquatic Invasive Species Grade Level: 3-8 Summary: Students become native mussels, invasive zebra mussels, perch, walleye, or “plankton movers” in a game Activity Duration: designed to help them understand how harmful invasive species Warm-up: 15 minutes can affect the balance within aquatic ecosystems. Activity: 20 minutes Wrap-up: 10 minutes Topic: Impacts of Aquatic Invasive Species Overview: Theme: Cause and Effect in Human and Natural Systems Warm-Up : Understanding Interactions Freshwater Mussels and Invasive Species Objectives: Activity: Simulating aquatic The students will: habitats and introducing an 1. Explain why native freshwater mussels are important to invasive species ecosystems. Wrap-Up 2. Identify the effects of zebra mussels on other aquatic organisms. 3. Describe three ways that zebra mussels can take over habitat in Minnesota waters. 4. List two ways in which human activity has introduced zebra mussels and two ways that people spread zebra mussels in Minnesota waters. Tools for building science 5. Describe the life cycle of a freshwater mussel, including literacy and understanding the how the larval forms of many mussel species require fish nature of science hosts during a stage of their development. This lesson is adapted from “Fishing: Get in the Habitat! Leader’s Guide, Lesson 3:7 – Mussel Mania” with permission from the MN DNR MinnAqua Program. http://tinyurl.com/mussel-mania http://undsci.berkeley.edu/ YouTube Video Series Introducing the Next Generation Science Standards http://tinyurl.com/ajy3fhq Cause and Effect - Science Institute 2014-2015 2 Next Generation Science Standards Crosscutting Concepts: Case and Effect Cause and effect is often the next step in science, after a discovery of patterns or events that occur together with regularity. A search for the underlying cause of a phenomenon has sparked some of the most compelling and productive scientific investigations. “Any tentative answer, or ‘hypothesis,’ that A causes B requires a model or mechanism for the chain of interactions that connect A and B. For example, the notion that diseases can be transmitted by a person’s touch was initially treated with skepticism by the medical profession for lack of a plausible mechanism. Today infectious diseases are well understood as being transmitted by the passing of microscopic organisms (bacteria or viruses) between an infected person and another. A major activity of science is to uncover such causal connections, often with the hope that understanding the mechanisms will enable predictions and, in the case of infectious diseases, the design of preventive measures, treatments, and cures.” Progression at Grades 3-5 Students routinely identify and test causal relationships and use these relationships to explain change. They understand events that occur together with regularity might or might not signify a cause and effect relationship. Progression at Grades 6-8 Students classify relationships as causal or correlational, and recognize that correlation does not necessarily imply causation. They use cause and effect relationships to predict phenomena in natural or designed systems. They also understand the phenomena may have more than one cause, and some cause and effect relationships in systems can only be described using probability. Suggested MN Science Standards: This lesson may partially or fully address the following standards. Grade 3: 3.1.1.2.4 – Construct reasonable explanations based on evidence collected from observations or experiments. 3.1.3.2.1 – Understand that everyone can use evidence to learn about the natural world, identify patterns in nature, and develop tools. 3.4.3.2.2 – Give examples of differences among individuals that can sometimes give an individual an advantage in survival and reproduction. Grade 4: 4.3.4.1.1 – Describe how the methods people utilize to obtain and use water in their homes and communities can affect water supply and quality. Cause and Effect - Science Institute 2014-2015 3 Grade 5: 5.1.1.1.4 – Understand that different models can be used to represent natural phenomena and these models have limitations about what they can explain. 5.3.4.1.3 – Compare the impact of individual decisions on natural systems. 5.4.2.1.1 – Describe a natural system in Minnesota, such as a wetland, prairie, or garden, in terms of the relationships among its living and nonliving parts, as well as inputs and outputs. 5.4.4.1.1 – give examples of beneficial and harmful human interaction with natural systems. Grade 6: 6.1.2.1.4 – Explain the importance of learning from past failures, in order to inform future designs or similar products or systems. 6.1.3.1.1 – Describe a system in terms of its subsystems and parts, as well as its inputs, processes and outputs. Grade 7: 7.4.2.1.1 – Identify a variety of populations and communities in an ecosystem and describe the relationships among the populations and communities in a stable ecosystem. 7.4.2.1.3 – Explain how the number of populations an ecosystem can support depends on the biotic resources available as well as abiotic factors such as amount of light and water, temperature range and soil composition. 7.4.4.1.2 – Describe ways that human activities can change the populations and communities in an ecosystem. Grade 8: 8.1.3.3.1– Explain how scientific laws and engineering principles, as well as economic, political, social, and ethical expectations, must be taken into account in designing engineering solutions or conducting scientific investigations. 8.3.4.1.2 – Recognize that land and water use practices affect natural processes and that natural processes interfere and interact with human systems. Cause and Effect - Science Institute 2014-2015 4 Materials: “Zebra Mussels Crash on Mississippi River” Sheet, one per student Plankton Sheet, one per student, or one transparency to project Tape, chalk, string, or rope for defining the lake boundary Two hula-hoops or bike inner tubes Newspaper or scrap paper crumpled into 100 or more tight balls, or 100 plastic golf balls, wiffle balls, or other substitute Mussels of Minnesota poster, available from the Minnesota DNR Information Center at 1-888-MINNDNR (646-6367) One legally collected native mussel shell (or other mollusk shell) Field Guide to the Freshwater Mussels of Minnesota, by Bernard E. Sietman (optional), available through the Minnesota DNR Bookstore http://files.dnr.state.mn.us/eco/nhnrp/mussel_survey/mussel_orderform.pdf Zebra Mussel Identification cards, one per student (optional), available from the Minnesota DNR Information Center at 1-888-MINNDNR (646-6367) Playing Area Diagram Cause and Effect - Science Institute 2014-2015 5 Vocabulary: Amphipods: A class of small Native: A species that has lived in a crustaceans; also referred to as scuds or particular region for thousands of years, side-swimmers. and, as such, has coevolved with its associates (other animals, plants, fungi, Carrying capacity: The maximum number and bacteria). It’s not enough for the of individuals or inhabitants that a given species to have reproduced in the area environment can support without for a few generations unaided by detrimental effects on the habitat or the humans—these species are described as organisms. naturalized, but not native. Conglutinates: A gelatinous case Plankton: Tiny microscopic organisms containing numerous developing mussel (plants and animals) that usually live larvae or glochidia. (See glochidia). suspended in the water and are eaten by fish and other aquatic life and form the Glochidia: A larval developmental stage base of aquatic food chains. of mussels. Glochidia mimic insects to entice fish to ingest them—the fish hosts Substrate: Bottom materials such as them for a stage of their development. rocks, gravel, or muck. (See conglutinate, mussel, and veliger.) Veliger: Free-swimming larva produced Invasive Species: Species or types of by zebra mussels. organisms introduced—intentionally or accidentally—into places where they’re Zebra mussel: Invasive (or non-native) not native and did not originally occur, clams, shorter than two inches across and adversely affect the habitats they that, by means of tufts of fiber (abyssal invade environmentally, ecologically, or threads) attach themselves to any solid economically. object. Their shells have dark “zebra” stripes and very sharp edges. Mollusk: An invertebrate animal with a soft, unsegmented body, usually enclosed in a shell. Cause and Effect - Science Institute 2014-2015 6 Instructor Background Information: Many people are unaware of the vast variety of animals that live under the surfaces of Minnesota waters. Mussels are one of these overlooked animals. Freshwater mussels inhabit the lakes and rivers in Minnesota, but they are found throughout the world, too, with North America supporting more species than any other continent. Mussels are members of the second largest group of animals in the world, the mollusks. Mollusks are invertebrates whose soft, unsegmented bodies are usually enclosed by a shell. Mussels belong to the phylum Mollusca, and are closely related to other bivalves, such as marine mussels and clams, as well as to snails and octopuses. Freshwater mussels have two shell halves, or valves. Inside the shell, a thin tissue—the mantle— surrounds the mussel’s soft body. The mantle secretes the material that creates the shell. The valves, held together by an elastic-like hinge, close with the help of two strong muscles whenever the mussel senses a threat. Why Are Mussels Important? Mussels are an important food source for several different kinds of animals, including river otters and raccoons, as well as several fish species. Mussel shells form an important substrate to which algae and insect larvae attach themselves. (A substrate is an underlying surface on which other organisms can grow—rocks, gravel, plants, woody debris, and mussel shells are all substrates). When present in large numbers, mussels can become a sort of underwater garden that attracts feeding fish, including their host fish.