Activity

How small is that?

In this activity, students fill a matchbox (or other small container) with tiny items to gain a greater appreciation of the tiny size of crab larvae and the relatively huge distances they swim to navigate their way back to their reef.

Raisin boxes are another great option instead of matchboxes. Any set of small containers will do well.

Settlement of crabs on reef habitats

In this video Jenni Stanley talks about her research with crab larvae and sound. She talks about where she got the idea to look at this phenomenon and why crab larvae might use sound to navigate.

Rights: University of Waikato

By the end of this activity, students should be able to:

  • appreciate the tiny size of crab larvae

  • appreciate the relatively huge distances they swim to navigate their way back to the reef from the open sea

  • calculate the proportional distance we, as humans, would need to swim to accomplish a comparable feat.

Download the Word file (see link below) for:

  • introduction/background notes

  • instructions on what you need and what to do

  • discussion questions

  • student worksheet.

Related content

Find out more about how larval crabs are attracted to the sound of a healthy reef and will use this to find their way home.

Useful links

Watch and discuss movie trailers on YouTube to get students thinking about ‘small’.

Published: 10 May 2011,Updated: 10 May 2011