Side-blotched lizards are lizards of the

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

''Uta''. They are some of the most abundant and commonly observed lizards in the deserts of western North America, known for cycling between three colorized breeding patternsSinervo, B.; C.M. Lively (1996). "The rock–paper–scissors game and the evolution of alternative male strategies". Nature 380 (6571): 240–243. doi:10.1038/380240a0. and is best described in the

common side-blotched lizard The common side-blotched lizard (''Uta stansburiana'') is a species of side-blotched lizard in the family Phrynosomatidae. The species is native to dry regions of the western United States and northern Mexico. It is notable for having a unique fo ...

. They commonly grow to 6 inches including the tail, with the males normally being the larger sex. Males often have bright throat colors. These lizards are prey for many desert species.

Snake Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more j ...

s, larger lizards, and

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

s all make formidable

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

s to side-blotched lizards. Larger lizard species, such as collared, leopard, and spiny lizards, and

roadrunner The roadrunners (genus ''Geococcyx''), also known as chaparral birds or chaparral cocks, are two species of fast-running ground cuckoos with long tails and crests. They are found in the southwestern and south-central United States and Mexico, us ...

s are the main predators. In turn, the side-blotched lizards eat arthropods, such as

insect Insects (from Latin ') are pancrustacean hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body ( head, thorax and abdomen), three ...

spider Spiders ( order Araneae) are air-breathing arthropods that have eight legs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude silk. They are the largest order of arachnids and rank seventh in total species ...

s, and occasionally

scorpion Scorpions are predatory arachnids of the order Scorpiones. They have eight legs, and are easily recognized by a pair of grasping pincers and a narrow, segmented tail, often carried in a characteristic forward curve over the back and always en ...

s. As a result of their high predation rate, these lizards are very prolific breeders. From April to June, they breed, with the young emerging as early as late May. These inch-long young appear all through the summer, and into September. The diploid

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

number in most if not all species is 34, consisting of 12 macro- and 22

microchromosome A microchromosome (μChr) is a type of very small chromosome which is a typical component of the karyotype of birds, some reptiles, fish, and amphibians; they have yet to be found in mammals. They are less than 20 Mb in size; chromosomes whic ...

Sex

Side-blotched lizards are notable for having the highest number of distinct male and female morphs within a species: three male and two female. They show a diversity of behaviors associated with reproduction, which are often referred to as "alternative reproductive tactics".Taborsky,M & Brockmann HJ (2010) Alternative reproductive tactics and life history phenotypes. pp 537-586, In P. Kappeler, Ed. Animal Behaviour: Evolution and Mechanisms. Springer Berlin Heidelberg Orange-throated males are "ultra-dominant, high

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristi ...

", that establish large territories and control areas that contain multiple females. Yellow stripe-throated males ("sneakers") do not defend a territory, but cluster on the fringes of orange-throated lizard territories, and mate with the females on those territories while the orange-throat is absent, as the territory to defend is large. Blue-throated males are less aggressive and guard only one female; they can fend off the yellow stripe-throated males, but cannot withstand attacks by orange-throated males. Orange-throated females lay many small eggs and are very territorial. Yellow-throated females lay fewer, larger eggs, and are more tolerant of each other.Roughgarden, Joan (2004). ''Evolution's Rainbow: Diversity, Gender, and Sexuality in Nature and People''. University of California Press. Especially chapter 6, ''Multiple Gender Families'', pp. 90-93. This is called the rock paper scissors effect, borrowed from the name of the playground game, because the outcome of the mating success shows that one morph of the lizard takes advantage over another but not over the third. The orange and blue-throated males can sometimes be seen approaching a human "intruder". One speculation is that he could be giving the female(s) a chance to escape, but whether he is defending the female has not been documented. Another speculation is that he is highly motivated to engage whenever he sees movement on his territory, which he may be interpreting as a possible intruding male, or another female.

Systematics

The systematics and

phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spe ...

of the side-blotched lizards is very confusing, with many local forms and morphs having been described as full species.See e.g. Oliver (1943) Following the 1997 review of Upton and Murphy, which included new data from

mtDNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA ...

cytochrome ''b'' and ATPase 6

sequences In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is called t ...

, the following species can be recognized pending further research: * Enchanted side-blotched lizard, ''U. encantadae'' * Dead side-blotched lizard, ''U. lowei'' * Isla San Pedro Nolasco lizard, ''U. nolascensis'' * San Pedro side-blotched lizard, ''U. palmeri'' * Isla Santa Catalina side-blotched lizard, ''U. squamata'' *

Common side-blotched lizard The common side-blotched lizard (''Uta stansburiana'') is a species of side-blotched lizard in the family Phrynosomatidae. The species is native to dry regions of the western United States and northern Mexico. It is notable for having a unique fo ...

, ''U. stansburiana'' ** Western side-blotched lizard, ''U. (stansburiana) elegans'' ** Nevada side-blotched lizard, ''U. (stansburiana) nevadensis'' ** Northern side-blotched lizard, ''U. (stansburiana) stansburiana'' ** Eastern side-blotched lizard, ''U. (stansburiana) stejnegeri'' ** Plateau side-blotched lizard, ''U. (stansburiana) uniformis'' * Swollen-nosed side-blotched lizard, ''U. tumidarostra'' It is also important to note that the side-blotched lizard is different from the

References

* Collins JT (1991). "Viewpoint: a new taxonomic arrangement for some North American amphibians and reptiles". ''Herpetological Review'' 22(2): 42-43
PDF fulltext
* Grismer LL (1994). "Three new species of intertidal side-blotched lizards (Genus'' Uta'') from the Gulf of California, Mexico". ''Herpetologica'' 50: 451–474. *Murphy, Robert W.; Aguirre-León, Gustavo (2002). "The Nonavian Reptiles: Origins and Evolution". pp. 181-220. In: Case, Ted J.; Cody, Martin L.; Ezcurra, Exequiel (editors) (2002). ''A New Island Biogeography of the Sea of Cortés''. New York: Oxford University Press. 690 pp.
PDF fulltextAppendices 2-4
* Oliver JA (1943). "The Status of ''Uta ornata lateralis'' Boulenger". ''

Copeia ''Ichthyology & Herpetology'' (formerly ''Copeia'') is a quarterly peer-reviewed scientific journal covering research in ichthyology and herpetology that was originally named after Edward Drinker Cope, a prominent American researcher in these fiel ...

'' 1943(2): 97-107. (First page image) *Pennock, Lewis A.; Tinkle, Donald W.; Shaw, Margery W. (1968). "Chromosome Number in the Lizard Genus ''Uta'' (Family Iguanidae)". ''Chromosoma'' 24(4): 467-476. PDF fulltext
*Upton, Darlene E.; Murphy, Robert W. (1997). "Phylogeny of the Side-Blotched Lizards (Phrynosomatidae: ''Uta'') Based on mtDNA Sequences: Support for a Midpeninsular Seaway in Baja California". '' Mol. Phyl. Evol.'' 8 (1): 104-113. PDF fulltext
{{DEFAULTSORT:Side-Blotched Lizard Uta Lizards of North America Reptiles of the United States Reptiles of Mexico Lizard genera Taxa named by Spencer Fullerton Baird Taxa named by Charles Frédéric Girard