For the Love of Leaping Lizards!

Lizards have a ‘fly’ mechanism of fleeing from predators, as depicted by Sir David Attenborough in Season 1, Episode 3 of Planet Earth II. In the documentary, he explains that Draco lizards (genus Draco), who are merely the size of a pencil and have an appetite for ants, can soar over 30 meters in a single leap when threatened. It turns out that the genus Draco actually consists of around 21 species, but there are four very distinct lineages within the genus that all share a common ancestor. [1]. These lizards have evolved morphological adaptations for gliding, which involves a particular musculature that keeps the forelimbs connected to the patagium (a membranous structure between the forelimb and hindlimb). With this adaptation, Draco lizards can easily maneuver and control their trajectory [2].

Interestingly, the effectivity of gliding varies among different sizes of these lizards. Larger species of Draco lizards are poorer gliders in comparison to smaller species, who display increased variation in locomotor capabilities due to the skilled flexibility exhibited in the smaller lizards [3].

This ‘leaping’ escape mechanism is not solely restricted to Draco lizards, however. Research shows that arboreal geckos, which are also abundant in the rainforest, have evolved morphology, such as body size, that influences their locomotor acceleration [4]. Apparently, morphological adaptations to propel further can be applied to organisms beyond just reptiles as increased performance in maneuverability and horizontal traveling distance has also been observed in “flying” frogs [5].

by Divya Veludhandi

Planet Earth II, Season 1, Episode 3, Jungles, starting at approximately 8:48

References

1. Honda M, Ota H, Kobayashi M, Nabhitabhata J, Yong H & T Hikida. 1999. Phylogenetic relationships of the flying lizards, genus Draco (Reptilia, Agamidae). Zoological Science. 16(3):535-549.
2. Dehling JM. 2017. How lizards fly: a novel type of wing in animals. Public Library of 12(12): e0189573.
3. McGuire JA & R Dudley. 2005. The cost of living large: comparative gliding performance in flying lizards (Agamidae: Draco). The American Naturalist. 166, no. 1: 93-106.
4. Higham TE, Russell AP, & KJ Niklas. 2017. Leaping lizards landing on leaves: escape induced jumps in the rainforest canopy challenge the adhesive limits of geckos. Journal of the Royal Society Interface 131.
5. Emerson S & MAR Koehl. 1990. The interaction of behavioral and morphological change in the evolution of a novel locomotor type: “flying” frogs. Evolution. 44(8), 1931-1946.