Lizard vs. Hurricane: Natural selection at work
Updated: Jun 3, 2020
BREAKING NEWS: NATURAL SELECTION RESULTING FROM CATASTROPHIC HURRICANES
A French-US collaboration population study on Anolis scriptus, a small, brown/green-brown lizard found on the Bahamas Archipelago, took an unexpected turn when hurricanes Irma and Maria hit the Turks and Caicos islands. The savage weather conditions meant that many lizards did not survive. But.
The few, fortunate lizards that did survive had a unique anatomy: longer front limbs, larger toe pads, and shorter hind limbs. The longer front limbs and larger toe pads meant they were better able to cling to branches during the violent winds, and shorter hind limbs meant that they were less likely to captured the wind. The results were published today in Nature.
This unique study captures the effect of natural disasters on ‘overnight’ natural selection on functionally relevant traits. “As far as I know this is one of the first studies documenting differential survival after a catastrophic event like a hurricane”, says Anthony Herrel, Director of Research at the Biological and Cultural Diversities LabEx (Institut écologie et environnement, CNRS), National Museum of Natural History in Paris. “Previous studies have mostly documented impacts on survival, such as entire populations being wiped out after the passage of hurricanes, for example“.
One such recent study, published in Science in 2017, documented the effects of winter storms on the green anole lizard, which demonstrated selective survival.
In the context of global warming, we might see more of these events as a result of more severe and more frequent catastrophic events; these could represent a significant selective force on natural populations. “This will add to the ongoing selective pressures due to habitat destruction and fragmentation. Global warming may push certain animal and plant populations to brink of extinction“, says Professor Herrel.
Quote source: personal communication.
Hurricane-induced selection on the morphology of an island lizard, Colin M. Donihue, Anthony Herrel, Anne-Claire Fabre, Ambika Kamath, Anthony J. Geneva, Thomas W. Schoener, Jason J. Kolbe, Jonathan B. Losos. Nature, July, 25, 2018. DOI : 10.1038/s41586-018-0352-3