It's a Long Way Down

     Alright, so these last two days I've split my time between creating a "lab binder" and researching the ecology and locomotion of green iguanas. A lab binder is basically a binder filled with any information one may need while dissecting - diagrams of limbs with corresponding muscle locations and names, dissection techniques, origin and insertion point sheets for different muscles, etc. So far, I have several diagrams of lizard forelimbs and hindlimbs showing the muscles both superficially and deep. I also have several listings of all the different muscles I should find with their origins, insertions, and actions (abductor, adductor, flexor, extensor, etc.). Dr. Fisher also sent me a PDF file detailing exactly how to go about dissecting the iguana. Where to start the first cut, which direction to go, how to go about skinning the fingers and toes. That is also in there.
     My research of iguanas has turned up this so far: First off, iguana anatomy is not so different from, say, pig anatomy. They have essentially the same bones - the humerus, radius, and ulna in the forelimb; the tibia, fibula, and femur in the hindlimb; a spinal cord and a skull. Iguanas also have five fingers and toes, just like humans do. The only major difference is the orientation of the bones. Because lizards are quadrupeds, their forelimbs and hindlimbs serve different purposes than in bipeds. The muscles that move these limbs are also different. Some are bigger than those in humans, some are completely foreign, and some you are expecting but do not find.
     Green iguanas (Iguana iguana), are, as the name suggests, bright green. They often have dark stripes around their tails and spines up their backs (Lagasse, 2011). They are strictly herbivores, though some iguanas that migrated to Florida have begun eating snails (Townsend et al., 2005). They grow to be 3-6 ft long, 2/3 of that length being their tail (Lagasse, 2011), which will grow back if taken off by a predator (Stewart, 2004).
     Green iguanas live in tropical areas from Mexico to Southern Brazil. They dwell primarily around rivers where there is abundant foliage. These lizards are arboreal - they live in trees - which is partially why their digits are tipped with claws, to aid in climbing. They are also accomplished swimmers, able to stay under water for close to 40 minutes in a lethargic state. Their large tails aid in propulsion in the water. Often when threatened, iguanas will jump from the trees into the water, their hard scales able to protect them from a 50 ft drop (Stewart, 2004).                                                
     I also found some interesting behavioral characteristics of iguanas. Many juvenile iguanas live and sleep in groups not only for warmth but also for protection from predators. Scientists have found that iguanas that live in groups tend to grow faster than those alone. The lizards also tend to protect their siblings, with identification possibly deriving from scent. The brothers will often put themselves in front of their sisters, the reasoning supposedly being that inherited traits will more likely be passed down through females than males (Stewart, 2004).
     I don't know, iguanas are kind of cool. Though beware, there were also a bunch of articles about how iguanas carry a bunch of diseases and often infect infants if they are kept as pets. They are also eaten. Yum :)

AA

                                                        Works Cited

Lagasse, Paul. “Iguana.” Columbia Electronic    Encyclopedia, 6th Edition (2011): 1. MasterFILE Premier.    Web. 1 Mar 2012.

Stewart, Doug. “Friendly Dragon.” National Wildlife 42.5 (2004): 38R. MasterFILE Premier. Web. 1 Mar 2012.

Townsend, Josiah H., et al. “Predation of a Tree Snail Drymaeus multilineatus (Gastropoda: Bulimulidae) by Iguana iguana (Reptilia: Iguanidae) on Key Biscayne, Florida.” Southeastern Naturalist 4.2 (2005): 361-364.JSTOR. Web. 1 Mar 2012.