Download Animal Adaptations - Hatfield Marine Science Center

Clamming it Up
Clamming it Up is designed to be a one-hour hands-on program that introduces younger
students to concepts such as classification, sampling and data. During this class, students have the
opportunity to explore a sandy environment in one of our wet labs and discover a variety of clams
and other bivalves that are an important part of the local economy and coastal food webs.
Background
Clams are soft-bodied marine and freshwater organisms that as adults can range in size from
a few millimeters to over 8 inches. Clams are invertebrates, meaning they have no backbone, and
are in the phylum Mollusca, which also includes snails (gastropods), squids and octopuses
(cephalopods), and chitons (polyplacophorans). Clams are bivalves, meaning they have two hinged
shells that they can close tightly for protection, and as such are closely related to mussels, oysters,
and scallops. Although there are numerous species of clams found in the coastal waters of Oregon,
only a dozen are important contributors to the commercial and recreational fisheries here.
Other examples of Mollusks include scallops, nudibranchs, snails, and chitons
Most clams reproduce sexually by releasing large numbers of eggs and sperm into the water
where fertilization occurs. Clam larvae are planktonic and are carried by ocean currents for several
weeks before they undergo metamorphosis and settle to the bottom. Clams have a muscular foot
that they use to burrow into the sediment. Clams are filter feeders and have siphons for pumping
water over their gills, which remove both oxygen and plankton (food) from the water.
Clams are an important source of food for both land and marine predators. Everything from
predatory snails and sea stars to shore birds and raccoons (and even people) rely on juvenile and
adult clams for their survival. Numerous other filter feeding species consume clam larvae as a main
part of their diet.
Oregon Sea Grant Marine Education Program at Hatfield Marine Science Center
Because they are such an important resource, researchers regularly sample clam populations
to monitor numbers and size and control human harvest through establishing daily limits, size
restrictions, seasons, and area closures. Since clams and other bivalves are filter feeders they can
sometimes accumulate toxins in their tissues by feeding on toxic phytoplankton. Tissue samples are
also regularly tested and areas closed as a human health precaution.
Suggested Pre- or Post-Visit Activities and Resources

Have students collect shells from the beach and group them in the classroom based on
characteristics like color, shape, and patterns. Identify them if possible then create a mobile
of the shells for display in the classroom.

Discuss the importance of clams in marine and estuarine food webs. How many different
animals can students name that feed on clams?
Oregon Sea Grant Marine Education Program at Hatfield Marine Science Center

Have students create their own model clam using paper plates to better understand their
many different adaptations. Instructions can be found at:
http://curiositycrew.com/michaelglaser/clam.htm
Program Correlations to State Standards
Kindergarten
K.2 Interaction and Change: Living and non-living things move.
K.2P.1 Examine the different ways things move.
K.3 Scientific Inquiry: Science explores the natural world through observation.
K.3S.1 Explore questions about living and non-living things and events in the natural world.
K.3S.2 Make observations about the natural world.
Grade 1
1.1 Structure and Function: Living and non-living things have characteristics and properties.
1.1P.1 Compare and contrast physical properties and composition of objects.
1.1L.1 Compare and contrast characteristics among individuals within one plant or animal group.
1.2 Interaction and Change: Living and non-living things interact.
1.2L.1 Describe the basic needs of living things.
1.3 Scientific Inquiry: Science explores the natural world using evidence from observations.
1.3S.1 Identify and use tools to make careful observations and answer questions about the natural
world.
1.3S.2 Record observations with pictures, numbers, or written statements.
1.3S.3 Describe why recording accurate observations is important in science.
Grade 2
2.1 Structure and Function: Living and non-living things vary throughout the natural world.
2.1L.1 Compare and contrast characteristics and behaviors of plants and animals and the
environments where they live.
2.3 Scientific Inquiry: Scientific inquiry is a process used to explore the natural world using
evidence from observations.
2.3S.1 Observe, measure, and record properties of objects and substances using simple tools to
gather data and extend the senses.
2.3S.2 Make predictions about living and non-living things and events in the environment based on
observed patterns.
2.3S.3 Make, describe, and compare observations, and organize recorded data.
Oregon Sea Grant Marine Education Program at Hatfield Marine Science Center