Article Review: "Spontaneous magnetic alignment behaviour in free-living lizards"

Throughout this semester in herpetology we have learned about and witnessed how reptiles and amphibians orient themselves in regards to season, temperature, weather, home range, geomagnetically and many more. In particular, we delved into how reptiles and amphibians position their bodies when basking. This article by Diego-Rasilla, Pérez-Mellado, and Pérez-Cembranos discusses the potential of 2 species of wall lizards, Podacris muralis and Podacris lilfordi, aligning themselves geomagnetically. They recorded the spontaneous alignment of the two species of lizards to determine whether they were orienting themselves because of the sun azimuth, altitude, or the Earth's magnetic field. To conduct this study, they walked in lines until a lizard was spotted to record orientation, tied them to the geomagnetic values at the time of observation, and calculated orientation to the sun. 

For Podacris muralis, their head position significantly correlated with the vertical component and total intensity of the magnetic field. Also, the way the lizards were aligned significantly correlated with the rate of change in geomagnetic values. Yet, there was no correlation between geomagnetic values and the lizards' positions and their head directions weren't correlated to rate of change in geomagnetic values. For Podacris lilfordi, statistically significant findings for body alignment and head direction while basking along with geomagnetic field values were calculated. The rate of change in geomagnetic values correlates with body alignment and head position. 

So, these certain lizards align their bodies to orient with respect to the geomagnetic field axis. This doesn't mean that these lizards have awareness of the geomagnetic field, but still proves their ability to use magneto-reception. Other studies should be done to eliminate the possibilities of wavelength detection and also the possible affects of polarity. 

source: https://link-springer-com.nuncio.cofc.edu/content/pdf/10.1007%2Fs00114-017-1439-7.pdf