Read an Excerpt
EXCERPT FROM THE INTRODUCTION
"Lizards in Wonderland: Why California Has So Many Lizards"
If you are a Californian, especially a Southern Californian, you might take lizards for granted. Most kids in suburban areas go through a phase of capturing blue-belly lizards in their yards. Lizards scattering around our feet as we hike on a mountain trail are as much a part of the Californian landscape as oak trees and Red-tailed Hawks. In many Southern California communities, people are so used to the adorable geckos congregating around buildings’ outdoor lights that they forget these exotic lizards weren’t here until recently.
But lizards are not a given in many other states. When I was twenty years old, I spent a summer in South Dakota doing reptile surveys. We recorded lots of salamanders, toads, and snakes, but the two species of South Dakotan lizards (only two!) remained elusive. When I started asking locals if they’d seen them, they said, “Sure! Spring lizards are a dime a dozen. There are lots of ’em down by the creek.” Reader, I searched my heart out for those “spring lizards” week after week, with no luck. I did see plenty of big, beautiful tiger salamanders in the moist areas by the creeks, but no lizards. It finally dawned on me that these “spring lizards” and the tiger salamanders I saw in abundance were actually one and the same. To those locals, four legs and a long tail meant lizard, 300 million years of evolution separating amphibians and reptiles be darned.
Unlike in South Dakota, lizards of the reptilian variety are indeed one of the most common types of wildlife you will see in California. Why are lizards scarce in South Dakota and common in California? While many factors are at play, climate is a major one. The single biggest factor determining lizard diversity is temperature: most lizards like it hot. Southern California has a warm climate that affords lizards a long active season to capture prey, mate, and produce offspring. Lengthy winters are much less compatible with reptilian lifestyles. Another factor is the complexity of the environment. Imagine taking a flight from San Diego to Las Vegas. From your window seat, you would see lots of different habitats, from beach dunes and chaparral to concrete urban jungles, transitioning into forested mountains surrounded by lowland scrub, then finally the huge Mojave Desert. Plus, each of these habitats on its own is complex in terms of topography, elevation, plant life, and more. All these factors have facilitated the evolution of many specialized species of life in California—insects, fungi, plants, and just about everything else, including lizards.
There are many other reasons why lizard diversity in California is relatively high, but there is one in particular that we will return to over and over in this book. Southern California is home to a large—and ever increasing—number of non-native species of lizards. As I am wrapping up this book in the fall of 2024, at least fourteen species of non-native lizards can be found in Southern California. This means that one in five species of lizards in California is not native to this state and has been introduced, by people, on purpose or by accident, mostly within recent decades. In fact, after I had already completed a draft of this book and was in the editing phase, a colleague emailed to alert me to a new population of Bosc’s Fringe-toed Lizards (Acanthodactylus boskianus), native to the Middle East but found in October 2023 in an industrial area in Ventura County. Have we discovered this population in time to capture all the lizards, or will it become a permanent resident like so many others? By the time this book is in your hands, there could be even more established populations and species. Why? In each species account, I discuss the unique story behind each of these tailed invaders’ journeys into California. You will see that many of these species occupy suburban residential areas where they thrive in our yards, climb about brazenly on our houses, and take shelter underneath our roof tiles. The word for wild animals that thrive in areas around people is synanthrope (syn = with or together, anthro = people). Southern California, due to its warm climate and dense human populations, is a literal breeding ground for invasive, synanthropic lizard species.
Whether you are enjoying the antics of blue-bellies on an oak tree, searching the skeletons of dead Joshua trees for night lizards, or watching non-native geckos tussle on the outside of your living room window, California is truly a wonderland of lizards. But before we dive down this rabbit hole full of lizards together, let’s wrap our heads around the most basic, but surprisingly complicated, question of all: what exactly is a lizard?
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