User:Vportugal/Anolis gundlachi

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Anolis gundlachi, also commonly known as the yellow-chinned anole, Gundlach’s anole, or 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. A. gundlachi’s diet consists mainly of insects. This species is also known for signaling other lizards with modulated headbobs according to distance from the other lizard.

Description
Anolis gundlachi is a medium sized, sexually dimorphic lizard. Adult males have a snout-to-vent length of 68 mm and females have a snout-to-vent length of 45 mm. Adult body weight is three to seven grams. The body is a brown or olive-brown color with brown spots randomly along its length. This species also has a yellow-brown dewlap and blue eyes. Males have crested tails.

Habitat and Distribution
A. gundlachi is found in the inner rainforests of the Luquillo mountains in northeastern Puerto Rico. The lizard lives at altitudes between 244 meters and 1158 meters. A. gundlachi is a trunk-ground lizard, meaning it mainly lives and perches on the lower regions of large tree trunks. In fact, it rarely climbs higher than five meters from the ground. Preference for wide, woody vegetation helps the lizard remain hidden from predators, allows for better locomotion, and aids in scanning more area of its territory.

This lizard is native to Puerto Rico.

Male defense
Males display territorial behavior by patrolling around their territory and defend their perch against other a. gundlachi males.

Home range
A. gundlachi have been observed to return to relatively the same location to sleep on a nightly basis. This suggests the lizard reserves a specific area of its overall territory to designate for sleep. 15 minutes before sunset, the lizard approaches its sleep site, where it then lays horizontally on the leaf with its snout pointed toward the stem and remains there until dawn. Being immobile on the leaf is helpful for avoiding predation since lizards displaced from their sleeping site are preyed upon by nocturnal predators.

The plants the lizard chooses as sleep sites are usually adult trees taller than 1 meter with woody stems and branches. Sleep-sites are based on availability and not a specific attribute of the plant itself. Only lizards with a snout-to-vent length of about 40 mm used plants above 1 meter tall. There is also a positive correlation between the height of the sleep-site and lizard size. This means juveniles are separated from adults by height of their sleep site.

Diet
A. gundlachi is mainly an insectivore, eating large insects and arthropods. However, this lizard is known to have powerful jaws and has been observed to eat other anoles, small frogs, and snails. Other prey includes ants, sowbugs, and mayflies.

Reproduction and Lifestyle
A. gundlachi is an oviparous lizard, meaning offspring hatch out of an egg after being laid by the mother.

Signaling and displays
A. gundlachi males use square wave-like motion headbobs and dewlap flashes as a display for courtship or challenges against other males. Males modulate the amplitude of their headbob according to the distance away from another potentially inattentive lizard. This specific motion is used and modulated to be attuned to the properties of the species’ sensory system. The square wave-like motion is especially helpful for making sure the receiver can detect the display among the background foliage of the forest. Since males are constantly patrolling their territories, they have to frequently adjust the amplitude of their headbob as well depending on how far away another lizard is, such as larger amplitude if a lizard is farther away. However, the lizards use a smaller amplitude when at a shorter distance from another lizard. In addition, pattern and duration of the display is also adjusted depending on distance. Failure to modulate according to these factors can affect the ability of the displayer to attract mates and not being able to tell rivals they occupy a given territory, which can then escalate to agonistic encounters between the two males.

Escape behaviors
Anolis gundlachi’s escape behavior is affected by temperature, sex, and perch type. The lizard flees at greater distance from the threat at lower temperatures. In addition, females use vertical perches, which are safer, and have greater approach distances than males. Vertical perches are safer because they are taller and allow the lizard to escape above the reach of predators on the ground, as well as let the lizard climb more quickly. Adult males tend to escape by running long distances (greater than 40 cm) down a perch toward the ground or up a branch or tree trunk while juveniles tend to escape by running shorter distances (less than 25 cm), usually down toward the ground to take advantage of their brown body color to hide amongst the leaf litter.

Adults and juveniles
Adult males are more often found on large tree trunks, fallen logs, and large branches, which provide more safety than vertical perches. Juvenile a. gundlachi are found more frequently on narrow surfaces. Adult males perch on higher and broader perches than juveniles, as well as tend to walk more and jump less as a method of locomotion. Adult males tend to spend more time performing display behaviors to other a. gundlachi than juveniles. Adult males also scan the territory below their perch in a face-down survey posture more frequently than juveniles.

Predators
Predators of the a. gundlachi include the Puerto rican boa, the common coqui, and the Puerto rican lizard cuckoo.

Parasites
A. gundlachi is frequently parasitized by malaria. In fact, about 30% of the species are infected with the malaria parasites P. floridense and P. azurophilum. It has been observed that the lizards infected with malaria have a greater prevelance of injured tails resulting in hinderance by the parasite, but there needs more evidence of effects of the disease on a. gundlachi. Percentage of lizards infected can vary between sex and body size so that males are infected more than females.

Thermoregulation
A. gundlachi’s habitat is limited to the shaded rainforests of Puerto Rico. In a study by Rogowitz, it was observed that this species does not usually participate in thermoregulatory behaviors such as basking to compensate for variation in elevation in its habitat. After examining lizards from the low range (350-400 meters) and high range (850-900 meters) of its habitat, no change in metabolism rates was found that would help the lizard adjust to the difference in temperature due to altitude. There was also no change in metabolic rate when exposed to lower than usual temperatures, but there was a decrease in metabolism and loss of mass when exposed to higher temperatures than usual. This lack of capacity to compensate for temperature differences from altitude means A. gundlachi is limited to its mountainous, shaded environment to survive and thrive.