Colours, stripes reveal lizard character
doi:10.1038/nindia.2018.120 Published online 17 September 2018
Body stripes and colourful tails in lizards may indicate that they are diurnal in nature, ground-dwelling, have a higher body temperature than other lizard cousins and a dispensable tail, new research suggests1.
Researchers at Indian Institute of Science Education and Research (IISER) Trivandrum, who studied body and tail colouration in 1622 species of 36 lizard families, also found that colourful tails and stripes evolved together, which may suggest that they have similar or linked functions.
The function of body stripes and colourful tails has been a persistent question in evolutionary biology. The two major hypotheses regarding their functions are ‘deflection’ and ‘motion dazzle’. The colourful tail can ‘deflect’ the attack of the predator towards a dispensable tail. Also, the movement of a striped lizard can again disorient or ‘dazzle’ the attack away from its vital parts.
However, the ecological and physiological factors related to the evolution of stripes and colouration has not been explored. To investigate the association of eco-physiological traits with stripes and colouration, the IISER researchers studied several parameters such as dispensable tails, diurnal/nocturnal lifestyle, body temperatures and dwelling patterns (ground, arboreal or rock).
They found that the presence of striped and colourful tails was positively associated with diurnal activity, ground-dwelling, higher body temperature and dispensable tails. The study provides evidence of the protective functions of colourful and striped tails based on ecological and physiological patterns of lizards.
1. Murali, G. et al. Grab my tail: Evolution of dazzle stripes and colourful tails in lizards. J. Evol. Biol. (2018) doi: 10.1111/jeb.13364