The Natural Iguana

Behold the Green iguana (iguana iguana) Though commonly called green, they can come in a variety of colors, right from green, red, browns, blacks and even blue and albinos breeders are currently also playing around and new names and patterns are appearing every day. They are large semi arboreal lizards in the animal kingdom as they are categorised as:
 

Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Sauria
Family: Iguanidae

 

They come from a variety of tropical forest land habitats along the tropical rain belt in south and central Amercia. 

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Adults are often seen grazing vegetation sometimes by  angry residents who just made there garden look pretty. Males can be seen fighting over areas to establish mating territories, they can often be found taking refuge at a height in the trees, and favorably positioning themselves above water to make a get away in the event a predator tries to have iguana for lunch. 

 

The Green iguana is naturally found across Central and South America, from Sinaloa and Veracruz, Mexico, south to the Tropic of Capricorn in Paraguay and southeast Brazil, Peru, Costa Rica. This large lizard also inhabits many islands throughout the Caribbean region and the coastal eastern Pacific, and has been introduced into southern Florida and in Hawaii. This is the largest known lizard to occur within the borders of the United States (Conant and Collins, 1998; Campbell, 1998). (Campbell, 1998; Conant and Collins, 1998)

 

Historically the green iguana has not made a good captive pet, many grew so big and aggresive they have been released by there owners or escaped establishing populations in un-natural areas such as Feral  in parts of California, Florida and Hawaii and some Islands. 

 

• Habitat Regions tropical Terrterrestrial                   Testrial Biomes forest rainforest

• Aquatic Biomes lakes and ponds rivers and streams 

• temporary pools coastal brackish waterWetlands swamp

• Other Habitat Features

• suburban agricultural

 

 

Within three years, a young, 12 gram hatchling iguana can become a 1 kg adult (de Vosjoli, 1992). Upon hatching, the length of green iguanas ranges from 17 to 25 cm. Most mature iguanas weigh between 4 and 6 kg, but some in South America, with proper diet can reach up to 8 kg. These large lizards can reach head to tail lengths of around 2 m.

 

Although called green iguanas, these animals are actually variable in color. The adults become more uniform in color with age, whereas the young may appear more blotchy or banded between green and brown. Color of an individual may also vary based upon its mood, temperature, health, or social status. Such color alteration may aide these animals in thermoregulation.

 

In the morning, while body temperature is low, skin color will be darker, helping the lizard to absorb heat from sunlight. However, as the hot mid-day sun radiates upon them, these animals become lighter or paler, helping to reflect the sun rays and minimizing the heat absorbed. Active dominant iguanas usually have a darker color than lower-ranked iguanas living the same environment (Frye, 1995). Most color variation seen in this species is exhibited by males, and may be attributed in part to sex steroids. Six to eight weeks prior to and during courtship, males may acquire a bright orange or gold hue, although coloration is still related to dominance status (Frye, 1995).

 

Mature females, for the most part, retain their green coloring.Other distinguishing features of this species include a pendulous dewlap under the throat, a dorsal crest made up of dermal spines that run from the mid neck to the tail base, and a long tapering tail. The dewlap is more developed in adult males than females. Extensions of the hyoid bones stiffen and support the leading edge of this structure, which is used in territorial defense or when the animal is frightened. This fleshy structure also serves in heat absorption and dissipation when it is extended.

 

The laterally situated eyes are protected mainly by a immovable eyelid and freely mobile lower eyelid (Oldham and Smith, 1975). On the dorsal midline of the skull behind the eyes is a parietal eye. This sense organ, although not a true "eye," serves as a meter for solar energy, and aids in the maturation of sex organs, thyroid gland, and endocrine glands (Frye, 1995). The visual effect of this "eye" is mostly limited to the detection of predatory shadows from above.

The scales or plates on the head are larger and more irregular than the scales on the rest of the body. Below the tympanum there is a large rounded scale called the subtympanic plate. (De Vosjoli, 1992; Frye, 1995; Oldham and Smith, 1975)

 

• Other Physical Features

• heterothermic

• Sexual Dimorphism

• male larger 

• sexes colored or patterned differently 

• male more colorful 

• ornamentatio

• Ecosystem Impact

 

In addition to helping disperse seeds, iguanas provide a source of food for larger predatory animals, including humans. Like other amphibians and reptiles, iguanas can be indicators of environmental changes (Kaplan, 2002). Reptiles are more sensitive to environmental changes than are humans, and by watching their responses, we can be alerted to possible problems before they are large enough for us to detect with our own senses. (Kaplan, 2002; Phillips, 1990)

 

Economic Importance for Humans: Positive

 

Iguanas are farmed in some countries as a source of food and leather, as well as for the pet trade. Due to their large size, iguana hides provide a source of luxury leather that can be made into boots, belts or purses. The pet industry also prizes iguanas; most are sold in the United States, Europe, and Japan. Iguanas also make an interesting tourist attraction in resort areas.

Exploitation of iguanas has resulted in marked declines in their numbers in some parts of their range. (Campbell, 1998). (Campbell, 1998)

• Positive Impacts

• pet trade 

• food 

• body parts are source of valuable material 

• ecotourism 

• research and education

Economic Importance for Humans: Negative

The most adverse effect green iguanas have on humans would be eating exotic tropical foliage in gardens. They do not pose any major problems for humans.

 

Because of there unique and majestic appearences they have became a favoured reptile pet in the reptile trade, very few reptiles can compete with the green iguanas impressive, majestic appearence, thus earning them a common title of the dinosaur of the living room. 

Unfortunately how-ever, they are a large commitment and there is much more to raising a healthy thriving animal than meets the eye.  There is a reason these animals are commonly abandoned and flood rescues and it takes a special kind of person with a special commitment to properly care for these animals. 

 

References 

S Rand G Burghartd Iguanas of the world 1982

E. R. Jacobson ed. (2003).Biology, Husbandry, and Medicine of the Green Iguana.

http://animaldiversity.org/accounts/Iguana_iguana/

http://icb.oxfordjournals.org/content/43/3/376.full

http://reptile-database.reptarium.cz/species?genus=Iguana&species=iguana