Side-blotched lizards are

lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...

s of the

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

''Uta''. They are some of the most abundant and commonly observed lizards in the

desert A desert is a landscape where little precipitation occurs and, consequently, living conditions create unique biomes and ecosystems. The lack of vegetation exposes the unprotected surface of the ground to denudation. About one-third of the la ...

s of western

North America North America is a continent in the Northern Hemisphere, Northern and Western Hemisphere, Western hemispheres. North America is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South Ameri ...

, 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 best described by the common side-blotched lizard. 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 reptiles of the suborder Serpentes (). Cladistically squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales much like other members of the group. Many species of snakes have s ...

s, larger

s, and

bird Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

s all make formidable

predator Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...

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

leopard The leopard (''Panthera pardus'') is one of the five extant cat species in the genus ''Panthera''. It has a pale yellowish to dark golden fur with dark spots grouped in rosettes. Its body is slender and muscular reaching a length of with a ...

, and spiny lizards, and roadrunners are the main predators. In turn, the side-blotched lizards eat

arthropods Arthropods ( ) are invertebrates in the phylum Arthropoda. They possess an arthropod exoskeleton, exoskeleton with a cuticle made of chitin, often Mineralization (biology), mineralised with calcium carbonate, a body with differentiated (Metam ...

, such as

insect Insects (from Latin ') are Hexapoda, hexapod invertebrates of the class (biology), class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (Insect morphology#Head, head, ...

spider Spiders (order (biology), order Araneae) are air-breathing arthropods that have eight limbs, chelicerae with fangs generally able to inject venom, and spinnerets that extrude spider silk, silk. They are the largest order of arachnids and ran ...

s, and occasionally

scorpion Scorpions are predatory arachnids of the Order (biology), order Scorpiones. They have eight legs and are easily recognized by a pair of Chela (organ), grasping pincers and a narrow, segmented tail, often carried in a characteristic forward cur ...

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 Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, ...

chromosome A chromosome is a package of DNA containing part or all of the genetic material of an organism. In most chromosomes, the very long thin DNA fibers are coated with nucleosome-forming packaging proteins; in eukaryotic cells, the most import ...

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

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 male sex hormone and androgen in Male, males. In humans, testosterone plays a key role in the development of Male reproductive system, male reproductive tissues such as testicles and prostate, as well as promoting se ...

", 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 Rock, Paper, Scissors (also known by #Names, several other names and word orders) is an Intransitive game, intransitive hand game, usually played between two people, in which each player simultaneously forms one of three shapes with an outstret ...

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 Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phy ...

and

phylogeny A phylogenetic tree or phylogeny is a graphical representation which shows the evolutionary history between a set of species or Taxon, taxa during a specific time.Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, M ...

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 and mDNA) is the DNA located in the mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the DNA contained in ...

cytochrome ''b'' and

ATPase ATPases (, Adenosine 5'-TriPhosphatase, adenylpyrophosphatase, ATP monophosphatase, triphosphatase, ATP hydrolase, adenosine triphosphatase) are a class of enzymes that catalyze the decomposition of ATP into ADP and a free phosphate ion or ...

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 call ...

, 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, ''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''

References

* Collins JT (1991). "Viewpoint: a new taxonomic arrangement for some North American amphibians and reptiles". ''Herpetological Review'' 22(2): 42-43
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* 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.
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* 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 fi ...

'' 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