Original air date: 4 February 2008

Above is a graphical presentation of the timeline of the programme, below is a more detailed text version
When a filming location is given with (no show) it means that Attenborough gave the location but did not appear on screen. That means it could have been filmed at any time during the filming of the series (or even taken from a collection). Any other filming were made during filming trips as discussed in Parson’s “True to Nature”.

Selected material
Sunbathing in safety

The horned lizard is so well hidden that marking it felt necessary to spot it in a snapshot (left). Only closer-up makes it relatively obvious (centre and right). It seems quite strange that having only the top of the body above ground is enough to deliver heat to the rest of the body. The computer graphics explain why.

The head warms up several degrees (left), and only when it has warmed up enough is the heat delivered to the part that is below ground (right).