Poems and Thoughts    by Frank Maurer

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Perhaps the Fastest Evolving Animal in the US! The American Spiny Lizard is changing--evolving--before our very eyes. This remarkable lizard resides in the southwestern US, And studies show its genetic shifts are occurring much faster than expected. Climate Change, urban expansion and predator pressure Are giving fuel to its rapid evolution. Most species have evolved over long periods of time-- This lizard in a few decades. Noteworthy is its developing resistance to toxins of invasive fire ants, Including a thicker skin and faster reflexes, evading the ants' attacks. Also urbanization is causing faster adaptation To hotter temperatures, with fewer sheltering areas. Studies demonstrate that urban dwellers Have higher heat tolerance than rural counterparts. With shifting metabolism, they remain active in temperatures normally fatal. Camouflaging colors have also shifted, blending in better With concrete and human structures. More noteworthy is the discovery that behavioral adaptations may be learned! Not just on instinct, these lizards watch, adapt, and problem-solve-- Especially the urban individuals who out-performed their rural cousins, By better navigating obstacles, escape traps, even recognize patterns. These results have major implications as to how animals Will cope with a rapidly changing planet. This certainly is evolution resulting from natural selection. Many lizards are thriving in human-altered environments, Seeking out heat-retaining structures and artificial water sources. Will these changes cause developmental switches To create an even more different species? This all demonstrates that 'Nature' is more flexible than ever imagined. The question is what other species are changing right before our eyes? Even our own species might follow this same pattern of adaptation. Nature seems to always find a way and never, generally, stands still. (Of course this group of lizards includes our local (Davis, CA) 'Blue Belly' or Western Fence Lizard.) Frank Maurer 8 March 2025 1250 Hours.