Behind the scenes: programme three
The gecko that begs for is supper
Deep in the forests of Madagascar, the team were told, lives a bright green day gecko that laps honeydew from sap-sucking insects. It had only been seen by one person a decade ago, and had never been filmed. Undaunted, cameraman Gavin Thurston and producer Miles Barton set out to capture this bizarre behaviour.
Finding the bright geckos against the tree trunks was relatively easy, but, for the first few days in the mosquito-infested forest, absolutely nothing happened. A different approach was required.
Local advice was to concentrate on the insects instead, and the geckos would appear to feed. But the plant hopper's camouflage was so perfect they were very difficult to find, being almost invisible against the tree trunk.
Eventually, a large day gecko ran down the tree trunk, approached an insect and chased away an ant. Could the honeydew be protection money for the gecko? They will never know because then it rained, the gecko disappeared and the downpour continued for two days.
Only on the last day did the team finally find an emerald green female gecko, conveniently about 3ft up a tree trunk begging from a plant hopper by nodding her head. It repeatedly responded with little balls of honeydew thrown from its abdomen that the gecko expertly caught in her mouth.
Fishing for a lizard
Filming the family life of the extremely shy pygmy blue-tongued skink was not going to be easy. They are only a few inches long and live in trapdoor spider burrows in the dry grasslands of South Australia.
For David, however, to get a decent view of one he would need some luck and a rod and line. It was hoped that a dead mealworm jiggled provocatively in front of the burrow would elicit a reaction. And it did, as David was practising his fishing technique before the crew had time to even get properly set up.
The result was half a mealworm on David's line and a satisfied skink licking its lips – one nil to the lizard. However, it was a hungry little animal and repeated the grab on several more occasions – holding on with a tenacious grip, and even allowing David to play it like a tiny trout so that he could see it out of its hole.
The team also wanted to film the family life of the lizards underground for the first time. They used a camera on the end of a flexible tube which could probe the 1ft-deep burrows. And there appeared the faces of one, two and then three babies alongside their mother – cramped in the tiny hole just like baby birds in a nest.
The lizard that walks like a beetle
Adult bushveld lizards which live in the deserts of South Africa are brown and well camouflaged against the sand. But baby bushveld lizards are very different, having dramatic black and white markings. Even stranger is the way they walk, with a hunchbacked gait unlike any other lizard or, indeed, their parents, making them even more conspicuous.
This seems to be a warning to predators. It's believed that the young lizards are imitating a local beetle in both colour and behaviour and that this beetle has a defensive trick.
To test this theory, David donned safety goggles and intrepidly picked up the beetle which then squirted formic acid at him. The beetle is appropriately known as an "oogpister", or eye-spitter, so, in a clever, defensive bluff, the baby lizard exploits the beetle's chemical defences for its own ends.