Monsters Sighted in Jalisco!
By Vern and Lori Gieger
monsters, that is. This elusive lizard spends the majority of its life
underground; in the summer to avoid the heat, during the winter months,
the Gila hibernates. Most of their above ground activity occurs for
three months in the spring, when mating occurs, and when their source
of food is most abundant. They are diurnal with activity occurring mainly
in the morning.
While the Gila is a non-aggressive lizard.
It will however, defend itself if approached too closely. In this case,
it will face its opponent with its mouth opened wide, hissing boisterously.
If the Gila feels further threatened it will jump at the aggressor and
bite. It was once believed that if a Gila monster bites, it will not
let go until sundown or until it thunders. Although, this is false,
Gilas do have a very powerful bite and are capable of hanging on tenaciously.
Another long-held belief has been that
the breath of a Gila monster is nauseating and poisonous. Nauseating
yes, poisonous no. Considering their diet, it is no wonder they have
serious halitosis! Their diet consists of carrion, (rotting flesh) various
insects and small reptiles and rodents.
The Gila is the source of many superstitions,
the subject of legends. Even the real facts about this misunderstood
creature are nothing short of amazing. Gila Monsters are one of only
two species of venomous lizards. There are two species of Gilas: the
reticulated, and the banded. While their bite is extremely painful,
there are no reliable accounts of human deaths from Gila monster bites.
Gila monsters are adapted to eating large meals infrequently. In fact,
an adult male Gila can consume its entire yearly energy budget in three
or four meals! Wow! Talk about a diet plan! However, their food requirements
are reduced by a low metabolic rate, as well as the relatively cool
body temperatures they maintain. Gilas have specially adapted tails
that allow them to store fat away for future needs. This allows them
to consume most of their food during the limited spring activity period.
(Well, I dont know whats so special about the tail; some
of us have specially adapted thighs, which allows us to store fat. Problem
is, it never seems to get used.)
Immediately after eating, large quantities
of a hormone-like molecule, called exendin-4 circulates in the Gilas
blood. With this unique mechanism of metabolic control, the act of eating
primes the organism to receive the incoming nutrients.
On an interesting note, Exendin-4 is currently being investigated as
a promising new drug to treat Type-2 diabetes. This peptide stimulates
the secretion of insulin in the presence of elevated blood glucose levels.
It also has the effect of slowing gastric emptying. Clinical studies
have recently begun with a synthetic version of this protein.
Humans tend to be the Gila Monsters
primary predator. This threat is primarily in the form of habitat destruction
and over-collection. Danger lurks in other places as well; other reptiles
eat the young Gilas. The adults are a food source for hawks and owls,
particularly the Harris hawk, and the Great Horned owl, not to mention
coyotes will not pass up the opportunity to dine on Gila. So, perhaps
its a good thing that they spend the majority of their life underground!