Posted on: July 13, 2012
Give them our plankton challenge to complete. Firstly, what are plankton? Plankton are microscopic plants (phytoplankton) and animals (zooplankton) that either float or are weak swimmers, carried by ocean currents. They are critical to the marine environment as they form the basis of most food chains and webs. The word plankton originates from the Greek word planktos, which means wandering or drifting. Many organisms living in the marine environment, being their life as a plankton, however some are plankton for the entirety of their lives.
Plankton must spend at least part of its life near the surface of the water where sunlight penetrates, referred to as the photic zone. This enables phytoplankton to capture sunlight to manufacture their own food via photosynthesis. Zooplankton graze on phytoplankton so need to be present where their food source is located.
Plankton exhibit a variety of adaptations to maintain close to the surface and slow their rate of sinking such as greater surface areas and long projections to increase friction.
To take the plankton challenge, you will need four consumables:
- Polystyrene shapes
- Toothpicks, and
- Straws (you may wish to cut these in half)
Get the kids to Google images of plankton, then using any of the above four materials, recreate the plankton. The key to the challenge is, that the recreated plankton must sit neutrally buoyant – that is, just below the surface in a bucket of water, it can’t sink to the bottom, but it can’t float on top of the water either. Get the kids to think about the adaptations plankton use in the marine world to stay close to the surface – large surface area and projections.