The Lifecycle of the Oyster
The sequential development and rapid changes in early life are the emphasis of this Oyster Lifecycle activity. The activity introduces new terms for specific stages of larval development and emphasizes the age, size, and characteristics of each stage. Although modeled on the traditional "cut-and-paste" format, students must use logical reasoning and background information to 'puzzel-out' the proper chronological order of the diagrams and labels. [Lesson Time: 30 to 45 minutes].
Objectives
1. Understand the basic stages of development in the oyster's lifecycle from larvae to adult.
2. Identify the names of important larval stages, sizes in microns, and key features of each stage.
3. Analyze information and search for trends in data. 4. To see clear diagrams, photographs, and computer images of microscopic larvae.
Materials
Supplementary Resource: http://www.hpl.umces.edu/facilities/oysters.html, Video Clips from Horn Point Laboratory's Oyster Hatchery

Procedure
Introductory Set:
1.  Introduce this activity by explaining that oysters begin life as microscopic lifeforms called larvae and that they are way too small to see with your eyes. Explain that as a larva (singular) grows and develops, it passes through distinct "stages" (just as people change from infants, to babies, to small children, to teenagers...etc).
2.  Students will learn the names and characteristics of these stages. If computer video projection equipment is available, show 10 second clips-- "Swarming video clip" (showing larvae moving amongst grains of sand) and "Settling video clip" (showing a "pediveliger" stage larva using its foot to attach)--from the http://www.hpl.umces.edu/facilities/oysters.html, Horn Point Laboratory-UMCES web site, to give a clear visual idea of what larvae look like.
 
Flow Chart:
1.  Have students review the activity handout ("The Oyster’s Lifecycle")and carefully read the background information.
2.  Distribute two cut-out pages, scissors, and glue stick. From the cut-out pages, students remove the diagrams and labels by cutting along the black lines.
3.  Allow students devise their own methods for arranging the information in the proper order on the Flow Chart. (See Teacher Key for notes and an organized table of lifecycle information).
4.  All informational pieces should be "dry fit" before being permanently glued down. The instructor could adjust the difficulty of the activity by adding or removing 'set' information from the Flow Chart. (Lesson Time: 30 to 45 minutes).
 
Alternative Lesson:
If time is extremely limited [Lesson Time: 15 minutes], use the Introductory Set above but substitute "An Oyster's Life", a Maryland Sea Grant activity published by the Maryland Department of Natural Resources (download from Lesson Resources). Answers: (1)Egg, (2)Spermatazoa, (3)Fertilized egg, (4)Embryo, (5)Free-swimming larvae, (6)Cilia, (7)Pseudopod, (8)Spat, (9)Adult oysters, (10)Bonus:"clutch."
References
Web site for Horn Point Laboratory Oyster Hatchery video clips, http://www.hpl.umces.edu/facilities/oysters.html
"An Oyster's Life" game appears in the The 2003 Maryland Bay Game booklet published by the Maryland Department of Natural Resources. Contact the Maryland DNR Public Communication Office at http://www.dnr.state.md.us
State Standards
1.5.5- The student will create and/or interpret graphics. (scale drawings, photographs, digital images, field of view, etc.)
1.5.7- The student will use, explain, and/or construct various classification systems.
3.2.1- The student will explain processes and the function of related structures found in unicellular and multicellular organisms.
Lesson Resources
--An Oyster's Life (Sea Grant)
--DIAGRAMS
--FLOW CHART
--LABELS
--STUDENT HANDOUT
--TEACHER KEY