Sexual dimorphism is the condition where sexes of the same species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most dioecious species, which consist of most animals and some plants. Differences may include secondary sex characteristics, size, weight, color, markings, or behavioral or cognitive traits. Male-male reproductive competition has evolved a diverse array of sexually dimorphic traits. Aggressive utility traits such as "battle" teeth and blunt heads reinforced as battering rams are used as weapons in aggressive interactions between rivals. Passive displays such as ornamental feathering or song-calling have also evolved mainly through sexual selection. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is monomorphism, when both biological sexes are phenotypically indistinguishable from each other.
Anolis carolinensis or green anole is a tree-dwelling species of anole lizard native to the southeastern United States and introduced to islands in the Pacific and Caribbean. A small to medium-sized lizard, the green anole is a trunk-crown ecomorph and can change its color to several shades from brown to green.
The broad-headed skink or broadhead skink is species of lizard, endemic to the southeastern United States. The broadhead skink occurs in sympatry with the five-lined skink and Southeastern five-lined skink in forest of the Southeastern United States. All three species are phenotypically similar throughout much of their development and were considered a single species prior to the mid-1930s.
The (American) five-lined skink is a species of lizard in the family Scincidae. The species is endemic to North America. It is one of the most common lizards in the eastern U.S. and one of the seven native species of lizards in Canada.
Podarcis muralis is a species of lizard with a large distribution in Europe and well-established introduced populations in North America, where it is also called the European wall lizard. It can grow to about 20 cm (7.9 in) in total length. The animal has shown variation in the places it has been introduced to. Fossils have been found in a cave in Greece dating to the early part of the Holocene.
The common side-blotched lizard 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 form of polymorphism wherein each of the three different male morphs utilizes a different strategy in acquiring mates. The three morphs compete against each other following a pattern of rock paper scissors, where one morph has advantages over another but is outcompeted by the third.
Urosaurus ornatus, commonly known as the ornate tree lizard, is a species of lizard in the family Phrynosomatidae. The species is native to the southwestern United States and northwestern Mexico. The species, which was formerly called simply the "tree lizard", has been used to study physiological changes during the fight-or-flight response as related to stress and aggressive competition. Its life history and costs of reproduction have been documented in field populations in New Mexico and Arizona. This species has been fairly well studied because of its interesting variation in throat color in males that can correlate with different reproductive strategies,
Scincella lateralis, formerly Lygosoma laterale is a small species of skink found throughout much of the eastern half of the United States, and into northern Mexico. The ground skink differs from the majority of North American lizard species in that it is generally considered a forest dweller. Common names for this species include the little brown skink and the ground skink. However, the common name, ground skink, may refer to any species in the genus Scincella.
Lampropholis delicata, the delicate skink, dark-flecked garden sun skink, garden skink, delicate garden skink, rainbow skink or plague skink, or the metallic skink is native to Australia and invasive in New Zealand and Hawaii where it is commonly found in gardens. The species is known for their color dimorphism between males and females; striped morphs and non-striped morphs exist in this species, however the stripe is less pronounced in males. This species' diet consists of a wide range of prey, such as spiders, bees, larvae, and termites. Mating occurs in the late summer and generally one clutch of 2 to 4 eggs are laid per year by each female.
The fire skink, also known commonly as Fernand's skink, the Togo fire skink, and the true fire skink, is a fairly large skink, a species of lizard in the family Scincidae. The species is known for its bright and vivid coloration. Native to tropical forests in West and Central Africa, the fire skink lives fifteen to twenty years. This species is a diurnal lizard that burrows and hides. It is relatively shy and reclusive, but may become tame in captivity.
Morethia boulengeri is a species of lizard in the family Scincidae. The species is endemic to Australia.
Eulamprus quoyii, more commonly known as the eastern water skink, eastern water-skink, or golden water skink, is a viviparous species of diurnal skink. Eulamprus quoyii belongs to the family Scincidae and is considered a common garden animal in Australia. The skink is endemic to Australia and found only along the east coast of the country. It makes its home in creekside habitats along the east coast of Australia and in urban garden areas with high amounts of moisture. The species can be identified by the twin, long yellow stripes that run along its body from the top of the eye, as well as by several more specific character derived states. The pale yellow dorsolateral stripes are most likely where its common name, the golden water skink, is derived. Like other ectotherms, the skink can often be seen basking in the sun on rocky outcroppings in order to regulate its body temperature. Its diet mainly consists of both aquatic and terrestrial insects, tadpoles and small amounts of plant matter. The skink both hunts for food and scavenges when necessary and is considered an opportunistic feeder. It is prey to larger lizards, snakes, cats and birds and so will often be seen moving quickly into hiding when other organisms are present.
Microlophus occipitalis, colloquially known as the knobbed Pacific iguana, is a lizard included within the Tropiduridae family. It is a member of the Microlophus genus and thus also considered a lava lizard. The knobbed Pacific iguana is found primarily in Western Peru and Ecuador, lining the coasts. The habitats of the knobbed Pacific iguana can be considered to be both broad and diverse as they are typically found in many different places such as beaches, lomas, and all the way to desert regions. This diversity is furthered as these lizards can also be found in open areas, between rocks, or bushes.
Sexual selection in scaled reptiles studies how sexual selection manifests in snakes and lizards, which constitute the order Squamata of reptiles. Each of the over three thousand snakes use different tactics in acquiring mates. Ritual combat between males for the females they want to mate with includes topping, a behavior exhibited by most viperids in which one male will twist around the vertically elevated fore body of its opponent and forcing it downward. It is common for neck biting to occur while the snakes are entwined.
The desert rainbow-skink is an Australian skink in the genus Carlia, commonly known as four-fingered skinks, from the subfamily Lygosominae. It is native to desert woodland regions throughout most of the Northern Territory, the north of Western Australia, and the far north-west of South Australia. It was originally classified as Leiolopisma triacantha, and is sometimes known as the three-spined rainbow-skink.
Ctenophorus decresii, also known commonly as the tawny dragon or the tawny crevice-dragon, is a species of lizard in the family Agamidae. The species is endemic to Australia. The average snout-to-vent length (SVL) of the species is 80.76 mm (3.180 in) with larger individuals being around 89 mm (3.5 in) and smaller individuals around 72 mm (2.8 in). The optimal time for mating in this species is two to three weeks after the females emerge from hibernation. Eggs are typically laid from September to October with most of them being laid earlier in the period. C. decresii is known for its variations in throat colors which change based on environmental conditions. Its primary food sources consist of both vegetation and invertebrates, and it prefers to live in rocky habitats.
Carlia longipes is a species of skink, commonly known as closed-litter rainbow-skink, in the subfamily Eugongylinae.
Diploderma swinhonis, also known commonly as the Taiwan japalure, Swinhoe's japalure, Swinhoe's lizard, and Swinhoe's tree lizard, is a species of lizard in the family Agamidae. The species is native to Taiwan. It is considered an invasive alien species in Japan after likely being transported from Taiwan by humans. A foraging ambush predator, this lizard preys primarily on arthropods and thus remains at the bottom of forests perched on trees where sunlight is present. D. swinhonis is not a major threat to humans and is able to adapt to a variety of habitats, including urban environments. The male D. swinhonis is physically distinct from the female, with its body size being much larger and having a yellow stripe. This species sexually reproduces on a seasonal basis and hibernates during the winter time.
Notomabuya is a genus of skinks. It contains one species, Notomabuya frenata, which is found in South America (Brazil, Bolivia, Paraguay, and northeast Argentina.
Carlia beccarii is a species of skink, a lizard in the subfamily Eugongylinae of the family Scincidae. The species is endemic to Indonesia.
