Objective – To investigate adaptation and design of cetaceans;
considering how their bodies are designed to minimise water
resistance.
Resources – Video footage of cetaceans (suggested BBC DVD
‘Blue Planet,’ or you can use other footage –
http://www.break.com/index/amazing-dolphin-pod-footage.html
http://news.bbc.co.uk/1/hi/wales/8308796.stm)
dynamic dolphin worksheets, extension activity power-point and ID
worksheets and dolphin anatomy worksheets.
National Curriculum Targets and Key Skills
Science KS2
Living things in their environment
5b Adaptation - About the different plants and animals found in different habitats
Forces and Motion
2c Types of force - About friction, (including water resistance,) as a force that slows
moving objects
Scientific enquiry – investigative skills
2l - use their scientific knowledge and understanding to explain observations,
measurements or other data or conclusions
Literacy KS2
Creating and shaping texts
Year 3 - use layout, format graphics and illustrations for different purposes
Year 4 - choose and combine words, images and other features for particular effects
Linked to Science QCA unit 4E Friction
Compiled by Sarah Langford
What to do 1.
Introduce the concept that friction is a force, of which water resistance is an example. Together
think of examples of when we have experienced water resistance, for example, swimming,
canoeing/kayaking, sailing and paddling in the sea.
2. Discuss how hard it can be to move through water, especially for example when we walk/paddle
through deeper water, and yet marine life has to be able to move quickly through water to avoid
prey and to be the predator! Ask children to jot down ideas in pairs as to how they think marine
life and mammals such as the dolphin may have adapted to reduce the impact of water resistance.
N.B. It may be useful to demonstrate the force of water and how it is displaced by allowing
children to push objects through water in a clear plastic box. Focus on the fact that the force
they can feel when they are moving objects through water is called water resistance, and that
water resistance slows moving objects down.
3. Explain that they will watch some footage of marine mammals, namely dolphins, moving through the
water whilst hunting and feeding. Whilst watching the footage they need to consider their earlier
ideas about how the dolphins have adapted to the marine environment, focusing specifically on the
shape of their bodies. Children can make notes on white-boards for discussion after.
In addition to the video links on the first page, there are specific references to the BBC
Blue Planet DVD’s below, that demonstrate how brilliantly designed marine life is –
The Blue Planet DVD 1 6:15 – 7:20 – Dolphins swimming
14:50 – 18:30 – Excellent example of common dolphins swimming and hunting, sharks and
Bryde’s whale.
DVD 2 Seasonal Seas 35:40 – 36:40 – Pacific white-sided dolphin
44:55 – 46:50 – Orcas hunting herring.
4. Discuss adaptations of dolphins and review earlier ideas, introduce and discuss the term
streamlined. Children complete the Dynamic Dolphins worksheet.
Extension activities –
1. Dolphin anatomy worksheets (reference books may also be useful for this activity)
2. Powerpoint activity encouraging children to use their observational skills by looking at photos
of features of different cetaceans and matching them to their pictures with names.
Information on observing cetaceans can be found at http://www.seawatchfoundation.org.uk/observing.php?uid=16
3. From watching the BBC Blue Planet sequences, they could annotate their Dynamic Dolphin
worksheet with notes about strategies the dolphins use to hunt, e.g. teamwork, surrounding
prey, banging their flukes and use of bubble netting to group fish – see link for info.
http://www.isvr.soton.ac.uk/FDAG/UAUA/RESEARCH/echolocation%20and%20bubbles/echoloc
ation%20and%20bubbles%201.htm
Compiled by Sarah Langford