| Anolis auratus | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Suborder: | Iguania |
| Family: | Dactyloidae |
| Genus: | Anolis |
| Species: | A. auratus |
| Binomial name | |
| Anolis auratus Daudin, 1802 | |
Anolis auratus, the grass anole, is a species of lizard in the family Dactyloidae. The species is found in Costa Rica, Panama, Venezuela, Colombia, French Guiana, Guyana, and Brazil. [2]
Though A. auratus presents a variety of physical characteristics based on geographic location, maturity, and sex, it commonly displays a tan dorsal surface with cream or dark brown to black lateral stripes, copper orange spots on the posterior thigh, a bright orange tongue, as well as an overall tan tail with light gray or black streaks, blotches, or stripes on the dorsal surface but orange coloration underneath. The female has a smaller dewlap with gray to blue skin in between cream scales, while the male possesses a larger dewlap, similar in skin color to that of the female but with yellow scales at the center and base of the structure. [3]
In general, male and female A. auratus exhibit differences in pelvis width, trunk length, and head size, and thus, are sexually dimorphic with females possessing bigger pelvises and trunks and males having larger heads. As females play a more important role in reproduction, their larger trunks and wider pelvises allow them to carry more eggs as well as oviposit, or lay, heavier and bigger eggs respectively. On the other hand, males exhibit larger head dimensions than females, which may be attributable to their participation in male-to-male competitive interactions for female mates, resources, and/or territories. Predominantly used as a weapon during male-to-male combat, the head size plays a significant role in establishing dominance, territoriality, fitness, as well as mating success since a bigger head may be associated with greater jaw strength and thus, stronger bite force. [4]
A. auratus is widely distributed throughout Central America as well as northern regions of South America, extending from Costa Rica and spanning through much of Colombia, Venezuela, Brazil, Surinam, and the Guyanas.
Unlike other Anolis species, A. auratus inhabits moderately verdant grasslands rather than arboreal, or branchy, environments, which researchers presume may have given rise to its unique social organization. It prefers to live in fields, roadsides, or river edge marshes, and avoid shaded, brushy, as well as second growth regions. These grassy habitats are extremely short-lived, as they develop from some kind of disturbance to the area, like flooding, burning, or clearing by humans, and eventually become uninhabitable, growing into secondary forests. Hence, the grass anole doesn't occupy a single permanent territory throughout its lifetime; rather, it is continually on the move from habitat to habitat, relocating once its previous dwelling is destroyed by a disturbance or eliminated via natural processes. Moreover, vegetation is dense near the ground with long grass stalks sprouting out, which leaves any and all elevated perches in the area – primarily used by males for assertion displays – exposed. In addition, insolation is higher in grassy habitats than arboreal ones, suggesting that A. auratus has adapted to tolerate and ultimately favor higher temperatures. [5]
A. auratus is mainly found in Panama but can be found across northern South America in open, grassy areas such as fields. It tends to avoid shaded areas. [6]
Described as a sit-and-wait predator, A. auratus forages for its food by spending most of the day sitting and waiting for prey to pass. Its diet consists mainly of invertebrates, more specifically arthropods, including Hymenoptera, Hemiptera, Chilopoda, Araneae, Orthoptera, and larvae. Generally, it is known to be an opportunistic feeder, ingesting a wide variety of arthropods and selecting prey on the basis of size rather than species type or identity. Furthermore, the size of the grass anole significantly affects the size of its prey, as bigger lizards have larger mouths, to effectively consume more massive arthropods. Diet may also vary throughout the seasons.
Males almost exclusively use their territories for access to mates rather than access to food since competition for food is low within the species. Males use displays to assert dominance over others males and attract females. [7] These displays consist of moving the head and dewlap up and down in a sinusoidal fashion. [7] A territorial male will approach another lizard to perform its display, and the sex and response of the conspecific will determine the result of the challenge. If the conspecific is female or a juvenile, it is tolerated within the male's territory. If the conspecific is another adult male, it is tolerated if it gives a head nod, but is chased away or engaged in agonistic behavior if it does not give a head nod or gives a challenge display. If the adult male conspecific loses the challenge, it can stay within the territory as a subordinate. [6]
Since A. auratus' habitat has abundant vegetation, the effectiveness of head displays may be affected by the moving vegetation, especially in the wind. Displays can also be affected by the vantage point of females, which are usually low in the grass and become habituated to movement patterns in the moving vegetation. Therefore, displays are most successful when using a sinusoidal movement pattern when there is no wind, but even with wind, displays are able to generally avoid reduction in effectiveness from habituation. [7]
The social system of A. auratus is described as that of a "tyrant-subordinate" system, in which there is one dominant territorial male with subordinate underlings occupying the same domain, and the latter group of lizards does not form dominance relationships amongst themselves. This social hierarchy has been observed and maintained during breeding seasons at natural population densities in the grass anole, rendering the behavior unique to this species, and many researchers attribute this phenomenon to the nature of the grassy habitat. Due to the transient formation and destruction of grasslands, subordinate males assume a higher net risk when challenging dominant males for territory ownership since the former must endure the high costs of fighting only to enjoy territorial dominion for a brief moment; thus, subordinates do not stand up against and engage in territorial battles with their dominants, as they will all have to relocate once their current grassy habitation becomes uninhabitable anyway. In accordance with this reasoning, dominant males also save energy by not forcing and driving out all the subordinate males from their territories, ultimately preserving the social organization. Furthermore, the exposed perches of these verdant lands make it difficult for subordinates to participate in displays for mating without getting caught by the dominant territory owners, leaving the subordinates no other choice but to comply. Consequently, the distinct "tyrant-subordinate" social system is maintained in A. auratus as a result of habitat demands.
Additionally, research studies show that individual A. auratus lizards prefer to associate with one another irrespective of size or sex. While in the absence of other conspecifics, they socialize with A. tropidogaster – a morphologically similar species. Previously, conspecific recognition was presumed to solely play a role in mate selection, aiding in reproductive isolation; however, the association of A. auratus with A. tropidogaster when conspecifics are not present as well as the tendency for same sex individuals to associate with one another suggest a purpose beyond reproductive selection. Accordingly, researchers attribute the attraction of conspecifics in the grass anole as a means of correct habitat selection, in which conspecifics are used as cues in deciding where one should settle in and occupy. The presence of conspecifics in a particular dwelling or environment may verify its suitability for livelihood in terms of resource availability and daily movements, in addition to potential for mates.
When given the choice of interacting with the same species or a morphologically similar species, A. auratus almost always chooses to interact with individuals of its own species. It only chooses to interact with other species when conspecifics are not around. This behavior suggests that being selective aids in reproductive isolation. It also suggests that being around conspecifics is important in habitat selection. [8]
Dactyloidae are a family of lizards commonly known as anoles and native to warmer parts of the Americas, ranging from southeastern United States to Paraguay. Instead of treating it as a family, some authorities prefer to treat it as a subfamily, Dactyloinae, of the family Iguanidae. In the past they were included in the family Polychrotidae together with Polychrus, but the latter genus is not closely related to the true anoles.
Anolis is a genus of anoles, iguanian lizards in the family Dactyloidae, native to the Americas. With more than 425 species, it represents the world's most species-rich amniote tetrapod genus, although many of these have been proposed to be moved to other genera, in which case only about 45 Anolis species remain. Previously, it was classified under the family Polychrotidae that contained all the anoles, as well as Polychrus, but recent studies place it in the Dactyloidae.
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 brown anole, also known commonly as the Cuban brown anole, or De la Sagra's anole, is a species of lizard in the family Dactyloidae. The species is native to Cuba and the Bahamas. It has been widely introduced elsewhere, via the importation and exportation of plants where the anole would lay eggs in the soil of the pots, and is now found in Florida and as far north in the United States as southern Georgia, Texas, Louisiana, Tennessee, Mississippi, Alabama, Hawaii, and Southern California. It has also been introduced to other Caribbean islands, Mexico, and Taiwan.
A dewlap is a longitudinal flap of skin or similar flesh that hangs beneath the lower jaw or neck of many vertebrates. More loosely, it can be various similar structures in the neck area, such as those caused by a double chin or the submandibular vocal sac of a frog. More generally, it can be any hanging mass of skin, such as a fold of loose skin on an elderly person's neck, or the wattle of a bird. Dewlaps can be considered as a caruncle, defined as "a small, fleshy excrescence that is a normal part of an animal's anatomy".
Podarcis hispanicus, also known as Iberian wall lizard, is a small wall lizard species of the genus Podarcis. It is found in the Iberian peninsula, in northwestern Africa and in coastal districts in Languedoc-Roussillon in France. In Spanish, this lizard is commonly called lagartija Ibérica.
The knight anole is the largest species of anole in the Dactyloidae family. Other common names include Cuban knight anole or Cuban giant anole, highlighting its native country, but it has also been introduced to Florida. In its native Cuba, this large anole is called chupacocote.
Anolis pulchellus, the Puerto Rican anole, Puerto Rican bush anole, snake anole, or sharp-mouthed lizard, is a small species of anole lizard in the family Dactyloidae. The species is among the most common lizards in Puerto Rico, and also native to Vieques, Culebra, and the Virgin Islands.
Anolis cristatellus is a small species of anole, belonging to the Dactyloidae family of reptiles. The species is native to Puerto Rico and the U.S. and British Virgin Islands, with introduced populations in locations around the Caribbean. The males of A. cristatellus are easily recognizable by the fin running down the top of the tail, which is known as a "caudal crest". The females also have this crest, but it is smaller than that of the males. The species is often quite common in many areas on Puerto Rico, where it can be seen during the day passing the time on the lower parts of tree trunks, or on fences and the walls of buildings in urban areas, sometimes venturing down onto the ground in order to lay eggs, have a snack, or do other cursorial activities. Like many anoles, this species displays the characteristic behaviour of doing push-ups as well as inflating a pizza-like flap of coloured skin on its throat, known as a dewlap, in order to show others how dominant it is, and thus attract mates or intimidate rivals.
Anolis allisoni, also known commonly as Allison's anole or Cuban blue anole is a species of lizard in the family Dactyloidae. The species is endemic to Cuba, the Bay Islands and Cayos Cochinos off the mainland of Honduras, and Half Moon Caye off the mainland of Belize. There is also a single doubtful record from Cozumel, Mexico. Recently, the species has been documented in southern Florida. This diurnal species is commonly seen on palm trunks, and it feeds on invertebrates. It is among the relatively few anole species in which females may lay their eggs together, forming a communal nest.
Anolis bartschi, also known commonly as the Pinar Del Rio cliff anole, western cliff anole, and the west Cuban anole, is a species of lizard in the family Dactyloidae. The species is endemic to Cuba.
The Puerto Rican twig anole or dwarf anole is a species of small, arboreal anole endemic to Puerto Rico and primarily inhabiting the Cordillera Central from the Sierra de Cayey range in the Southeast to the central-western ranges of Maricao. A mostly grey to olive-brown bodied lizard, A. occultus is the smallest of the Puerto Rican anoles with a snout to vent length of 34–42 mm. In comparison to other twig anoles, A. occultus is extremely cryptic through its unique sleeping behaviors and mottled pattern. Sleeping behavior including site selection minimizes the probability of predator encounter along with A. occultus' extensive list of antipredator behaviors.
Anolis grahami, commonly known as the Jamaican turquoise anole and Graham's anole, is a species of lizard in the family Dactyloidae. The species is native to the island of Jamaica, and has also been introduced to the territory of Bermuda. It is one of many different species of anole lizards found in Jamaica. There are two recognized subspecies.
Anolis cuvieri is a species of lizard in the family Dactyloidae. The species is endemic to Puerto Rico, and is common in the Toro Negro State Forest.
Anolis proboscis, commonly known as the horned anole, Ecuadorian horned anole or Pinocchio lizard, is a small anole lizard in the family Dactyloidae. A single male specimen was discovered in 1953 in Ecuador and formally described by Peters and Orces in 1956, but the species then went unreported until its rediscovery in 2004. Its currently known habitat is a small stretch of vegetation along an Ecuadorian highway. It has been classified as Endangered by the IUCN due to its restricted distribution and ongoing habitat loss.
Lizards are among the most diverse groups of reptiles with more than 5,600 species. With such diversity in physical and behavioral characteristics, lizards have evolved many different ways to communicate. Lizards communicate to gain information about the individuals around them by paying attention to various characteristics exhibited by individuals and using various physical and behavioral traits to communicate. These traits differ based on the mode of communication being used.
Anolis apletophallus is a species of anoles, iguanian lizards in the family Dactyloidae native to Panama. The species was split from Anolis limifrons in Köhler and Sunyer (2008). It has been reported in Panama, Honduras and Colombia. A decline in its population in Panama over a 40-year timespan has been attributed to changes in local climate, with years following El Niño negatively affecting the species.
Anolis aquaticus, commonly known as the water anole, is a semi-aquatic species of anole, a lizard in the family Dactyloidae, native to southwestern Costa Rica and far southwestern Panama. The species demonstrates adaptations that allows it to spend periods of time underwater up to approximately a quarter of an hour, forming an air bubble which clings to its head and serves to recycle the animal's air supply while it spends time beneath the surface. Although highly unusual, similar adaptions and behavior are found in other species of semi-aquatic anoles.
Anolis evermanni, also known commonly as the emerald anole, Evermann's anole, and the small green anole, is a species of lizard included within the family Dactyloidae. A. evermanni is native to Puerto Rico, where it is mainly found in wet forests. A. evermanni is a medium-sized lizard and bright emerald-green in color. A. evermanni is studied for its behavior as well as the evolution of the family Dactyloidae. The group of lizards which are member species of the family Dactyloidae are known as anoles. Anoles are found throughout the Americas and are related to iguanas.
Anolis gundlachi, also commonly known as the yellow-chinned anole, Gundlach's anole, and the yellow-beard anole, is an oviparous, sexually dimorphic species of lizard in the family Dactyloidae. The species is endemic to Puerto Rico and lives in mountainous forests at high elevations. The diet of A. gundlachi consists mostly of insects. This species is also known for signaling other lizards through a modulated head bob display, with varying bobbing amplitudes and patterns based on an individual's distance from other lizards.
