Skilled forelimb movements and extractive foraging in the Arboreal monitor lizard varanus beccarii (Doria, 1874)

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Herpetological Review 42(3), 2011
ARTICLES 343
Scientists and enthusiasts who have studied, kept, or ob-
served monitor lizards (Varanidae: Varanus) for extended peri-
ods of time usually recognize that monitors possess considerable
intelligence when compared to other reptile groups. Scientific
testaments to their “higher intelligence” date back more than a
century, with both Ditmars (1902) and Werner (1904) recognizing
monitors as the pinnacle of lizard intelligence. Since then, many
herpetologists have followed suit in this claim (e.g., Burghardt
et al. 2002; Mertens 1942; Phillips 1994; pianka and King 2004;
Sweet and Pianka 2003), supported by research and behavioral
observations of their own as well as a growing number of pub-
lished accounts describing unusual and insightful behaviors in
the group (see reviews by horn 1999 and Krebs 2007). Formal
research on the memory and learning capacities of monitors has
also contributed to the general understanding of their intelli-
gence (loop 1976; Manrod et al. 2008).
Despite numerous published accounts on monitor behavior,
the insight and behavioral complexity of some species are better
understood than others. It is not surprising, given their size and
conspicuousness when compared to smaller tree-dwelling taxa,
that large terrestrial species ( > 1.5 m in total length [TL]) account
for most behavioral observations which have led to the idea of
intelligence in monitors (horn 1999; Krebs 2007). Even captiv-
ity-based studies on learning and behavioral complexity have
focused primarily on large terrestrial species (e.g., Burghardt et
al. 2002; Firth et al. 2003; Loop 1976; Manrod et al. 2008). Thus,
little is known about the problem-solving abilities and behavior-
al specializations of the more diminutive monitors, particularly
arboreal taxa belonging to the subgenera Odatria and Euprepio-
saurus.
Within Euprepiosaurus, the Varanus prasinus complex is
currently comprised of nine highly arboreal species (to ca. 100
cm TL) endemic to tropical lowland environments of northeast-
ern Australia, New Guinea, and adjacent islands (Ziegler et al.
2007). Behavioral observations on these species in the wild (e.g.,
Clarke 2004; Irwin 1994, 1996; Pattiselanno et al. 2007; Whit-
tier and Moeller 1993) and in captivity (e.g., Eidenmüller and
Wicker 1992; Garrett and Peterson 1991; Hartdegen et al. 1999,
2000; Irwin 1996; Kiehlmann 1999) are rather limited, but spe-
cific references to insightful behaviors are scant (Holmstrom
1993). Krebs (1991) doubted the insight of V. prasinus, grouping
it together with “less-specialized” monitor species on account
of a presumed “lower specialized learning ability.” This was be-
fore several published reports describing diverse prey-handling
tactics used by the V. prasinus complex (Hartdegen et al. 1999,
2000; Kiehlmann 1999), which Greene (2004) later recognized as
highly specialized behaviors. Here, we call special attention to
the insight and behavioral complexity of the V. prasinus complex
by describing a remarkable prey extraction behavior used by the
Black Tree Monitor, V. beccarii (Doria, 1874), which demonstrates
complex problem solving abilities, fine motor coordination, and
skilled forelimb movements.
METHODS
History and husbandry of specimens.—An adult male (242
mm in snout to vent length [SVL]) and female (270 mm SVL)
Varanus beccarii of unknown ages and of wild-caught origin
have been maintained for several years in the private collection
of RWM. Both specimens are housed in separate terraria each
measuring 90 x 60 x 180 cm (l x w x h). A 6 mm thick sheet of
acrylic doubles as a viewing window and access door for each
terrarium. Each terrarium is furnished with large tree limbs and
the walls are covered with cork sheeting and virgin cork slabs.
Live Pothos plants provide additional cover. A basking spot of
ca. 49°C is provided in each terrarium by outdoor Sylvania®100
watt halogen flood lamps, which also provide ambient lighting.
Daytime ambient temperatures range in a vertical gradient from
23.8°C at the floor to 40.6°C at the ceiling. Nighttime ambient
temperatures drop to 30°C. A small access door connecting the
terraria is periodically opened to allow the monitors access to
one another for breeding.
Since their acquisition, both specimens have been fed a ro-
tating daily diet of Zophobas morio larvae, domestic crickets
(Acheta domesticus), wood cockroaches (Nauphoeta cinerea),
wax moth larvae (Achroia grisella), and frozen-thawed neonatal
mice. Typical of many male monitor lizards in captivity, the male
Varanus beccarii quickly developed a strong feeding response,
and feeds aggressively from forceps. The female has remained
timid with a weaker feeding response, and only occasionally
accepts prey from forceps. Each specimen is fed at alternating
locations throughout its terrarium to prevent habitual feeding
locations and associated feeding aggression.
Beginning around April 2009, the male was infrequently of-
fered neonatal mice and Zophobas morio larvae through a per-
manent 15 mm gap which had formed in the upper left corner of
its terrarium between the acrylic door and the door frame. The
gap, created by the warping of the acrylic door over time, was
large enough to pass prey items through using forceps, but not
large enough for the monitor to fit its head through.
OBSERVATIONS AND RESULTS
Initial behavioral observations.—On 25 January 2010, the
male Varanus beccarii was fed a neonatal mouse through the gap
in the terrarium door. Following its consumption, the monitor
showed continued interest in the gap, now scented with mouse
odor, by repeatedly tongue-flicking the area. After ca. 15 seconds
of tongue-flicking, the lizard extended its right forearm through
ROBERT W. MENDYK
Center for Science Teaching and Learning
1 Tanglewood Road, Rockville Centre, New York 11570, USA
Center for Herpetological Education and Inquiry
P.O. Box 331, Mineola, New York 11501, USA
e-mail: odatriad@yahoo.com
HANS-GEORG HORN
Monitor Lizards Research Station
Hasslinghauser Str. 51
Sprockhoevel, Germany
e-mail: hans-georg.horn@rub.de
Herpetological Review, 2011, 42(3), 343–349.
© 2011 by Society for the Study of Amphibians and Reptiles
Skilled Forelimb Movements and Extractive Foraging in the
Arboreal Monitor Lizard Varanus beccarii (Doria, 1874)

Herpetological Review 42(3), 2011
344 ARTICLES
the opening, and began reaching around the outside frame of
the terrarium with its forehand. The lizard retracted its arm back
into the terrarium, then after another series of tongue flicks, it
extended its left forearm through the opening, performing the
same reaching arm movements as before, but reaching a farther
extension than with the right arm. This sequence of behaviors
was repeated several more times over the next minute until the
monitor apparently lost interest.
To determine if this behavior was intended to locate or re-
trieve prey, a neonatal mouse was held by forceps just outside
the gap of the male’s terrarium, visible to the lizard. Once the
monitor noticed the mouse and recognized its scent, it immedi-
ately extended its left forearm through the gap, and began reach-
ing and clawing at the mouse with its forehand. These efforts
appeared frantic and were noticeably more coordinated than
earlier attempts when a prey item was not present. After keep-
ing the mouse out of reach for several unsuccessful retrieval at-
tempts, it was moved within reach of the monitor. The Varanus
beccarii hooked the prey with its claws using a grasping forehand
movement, then quickly pulled it back into the enclosure where
it was seized from the claws with the jaws and swallowed. Ad-
ditional trials were successfully repeated with both the male and
female (through a gap created by partially-opening the female’s
terrarium door), as well as with Zophobas morio larvae offered as
prey (Fig. 1).
It is important to note that these reaching and grasping fore-
arm movements involved highly coordinated wrist and digit ma-
nipulations (Fig. 1). A similar reaching behavior was observed at
the base of the male’s terrarium door whenever Zophobas morio
larvae would fall into a 7 mm wide, 30 mm deep channel running
along the length of the door (56 cm) between the door, frame,
and weather stripping. Alternating use of both forelimbs, the
male was able to retrieve the prey by inserting its forearm into
this groove then using a series of side-swiping arm movements
until the prey became snagged on a claw or was able to be pulled
upwards and out of the opening.
Semi-natural experiments.—Following these initial trials and
observations, a simple experiment was carried out to test the use
of this behavior in a semi-natural situation. A series of four holes
narrower than the width of the monitors’ heads measuring 15 x
35, 15 x 65, 20 x 35, and 20 x 65 mm (width x depth) was drilled
into one vertically-oriented and one horizontally-oriented tree
trunk (trunks ca. 15 cm in diameter) in each terrarium. A variety of
prey items, including Zophobas morio and Achroia grisella larvae,
fIg. 1. Male Varanus beccarii using reaching arm movements to retrieve a Zophobas morio larva through a gap in the terrarium door. A) The
forearm is extended through the opening, with the wrist angled back and the digits close together; B) the forearm reaches its furthest exten-
sion, with the wrist angled downward and the digits spread apart; C) contact is made with the prey item, and the digits are curled around the
prey; D) the prey is pulled through the opening with the claws to be seized with jaws and swallowed.
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Herpetological Review 42(3), 2011
ARTICLES 345
neonatal mice, and Acheta domesticus were placed inside these
holes during feedings to test whether each V. beccarii specimen
was capable and willing to use its forelimbs to retrieve the prey.
Using coordinated forearm movements, both V. beccarii
successfully retrieved all prey types from all four holes located
in each tree trunk. Both individuals used identical extraction
behaviors, including the same body positioning, reaching arm
movements, and sequences of movements.
Prey is extracted from the holes in vertically-oriented trunks
when the monitors are positioned either upright or inverted on
the trunk. Once a prey item is detected in a hole either by sight
(prey was seen as it was placed inside the hole) or smell, the
monitor carefully inspects the hole with a series of tongue-flicks.
After unsuccessfully attempting to enter the hole with its head,
the forearm is skillfully inserted into the opening, all while main-
taining eye contact with the prey inside (Fig. 2). The prey is then
either flushed from the hole or pulled out with the foreclaws,
where it is seized with the jaws and swallowed. The same be-
haviors are used on horizontally-oriented trunks (Fig. 3), though
when extracting prey, the monitor must lift the prey upwards
and out of the hole, requiring slightly different muscular move-
ments and greater coordination, which appeared to take more
concentration and effort than with holes in vertically-oriented
trunks. Occasionally, prey items are impaled and extracted from
the opening while still attached to the claws, where they are then
seized with the jaws and swallowed. Both individuals regularly
switch usage of each forelimb to maximize its depth of penetra-
tion into the hole, depending on its body positioning at the time.
Additional specimens.—Once this behavior was observed in
both Varanus beccarii specimens in RWM’s collection, another
keeper of the species was asked to test for the usage of this be-
havior in an additional adult female (265 mm SVL). When of-
fered mice through a small (ca. 13 mm) opening in the terrarium
door, the monitor repeatedly used the same reaching forearm
movements described herein to successfully retrieve the prey (S.
Sweet, pers. comm.). Likewise, this female also used its forearms
to successfully extract mouse parts from a 15 mm x 70 mm deep
hole drilled into a 15 cm thick, diagonally-oriented tree trunk
(Fig. 4).
DISCUSSION
Initial remarks.—Extractive foraging, the location and re-
trieval of food items from embedded matrices (Gibson 1986),
is rarely performed by non-avian reptiles, limited mostly to
fIg. 2. (left) Male Varanus beccarii using
coordinated forelimb movements to ex-
tract a Zophobas morio larva from a hole
in a vertically-oriented tree trunk. A) A
tongue flick into the hole confirms the
presence of prey; B) the monitor pulls
its arm back; C) the digits are pulled to-
gether, rendering them and the forearm
streamline for insertion into the hole; D)
the forearm is inserted into the hole and
jostled around to either flush out prey or
snag prey with the claws; E) the forearm is
retracted, pulling the prey out of the hole
with the claws where it can then be seized
with the jaws and swallowed.
fIg. 3. (above) Male Varanus beccarii us-
ing coordinated forelimb movements to
extract prey from a hole in a horizontally-
oriented tree limb.
PhoTo By roBerT w. meNdyK
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Herpetological Review 42(3), 2011
346 ARTICLES
monitor lizards (e.g., Eidenmüller 1993; Gaulke 1989; Sweet
2007). Similarly, skilled forelimb movements such as the abil-
ity to reach for and grasp food items are well-documented in a
number of mammalian groups (Iwaniuk and Whishaw 2000), but
few reptiles have the processing skills, motor coordination, and
dexterity needed to perform such movements. As far as we can
determine, this report is the first description of a reptile using
coordinated forelimb movements to extract prey from narrow
and otherwise inaccessible holes in trees. Often associated with
primates (e.g., Erickson 1994), tree hole prey extraction provides
further support for the idea that monitors share many biological
similarities with mammals (e.g., Wood et al. 1977; see also Horn
and Visser 1997; Sweet and Pianka 2007). Moreover, it specifically
highlights the problem-solving abilities and behavioral com-
plexity of Varanus beccarii, thereby supporting Greene’s (2004)
earlier statements regarding further behavioral specializations
in the V. prasinus complex.
Is forelimb-assisted extractive foraging learned or genetically-
fixed?—Given its apparent rarity among reptiles, the origin of this
foraging behavior in Varanus beccarii– whether independently
learned through insight, genetically-fixed, or some combination
of the two, is of particular interest. Extracting food from embed-
ded matrices often requires complex problem solving skills (Gib-
son 1986). Monitors do not typically rely on extractive foraging
because most prey is captured out in the open by dashing for-
ward and seizing it with the jaws. If successful, and if the prey is
of sufficient size, it is immediately swallowed. However, in cases
of embedded prey, the situation is complicated by the monitor’s
inability to use conventional prey capture techniques. Unable to
insert its head into a narrow opening to seize a prey item, the
monitor must devise an alternate capture strategy otherwise the
feeding opportunity may be lost. Here, in the case of V. beccarii, a
conscious decision derived through insight is made to abandon
use of the jaws and switch to an alternate technique that utilizes
a completely different set of motor skills. The ambidexterity of V.
beccarii while performing this behavior also
exemplifies keen insight given that switching
usage between forelimbs represents a fore-
sighted decision that will enable the monitor
to reach deeper into a hole, thereby increas-
ing its foraging effectiveness.
Unlike the decision-making component
of this behavior, we suspect that the skilled
forelimb movements used by Varanus bec-
carii to extract prey are instinctive, rather
than individually learned through insight.
Because all three V. beccarii tested in the
present study used the same reaching fore-
limb movements and body positioning while
performing the behavior, and were capable
of using them in different experimental situ-
ations, the most parsimonious explanation
for these consistencies is that the movements
have a genetic basis. Alternately, if the limb
movements were independently learned, we
would expect to have seen some individual
variation in body positioning and the perfor-
mance of this behavior.
Based on these interpretations, we con-
sider forelimb-assisted extractive foraging
in Varanus beccarii to be a mutual interac-
tion between insight learning and instinct,
and therefore expect it to occur in wild populations. However,
the ability to learn and successfully perform this behavior might
vary from individual to individual since monitors differ greatly
in their intellectual abilities (Lederer 1933, 1942). Loop (1976)
demonstrated that monitors are gifted with excellent memories,
and can remember trained, food-oriented procedures even after
several weeks of latency. Therefore, once learned by an individ-
ual and added to its behavioral repertoire, extractive foraging is
unlikely to be forgotten if it reliably produces feeding opportuni-
ties.
Requisites for use in the wild.—If forelimb-assisted extractive
foraging is to be a useful strategy for Varanus beccarii in the wild,
we contend that several conditions must be met. First, V. beccarii
would have to be an arboreal forager that feeds on tree-dwelling
prey, and second, it must forage in environments where both ar-
boreal prey and tree holes are abundant and accessible.
Scientific observations on the natural history of V. beccarii in
the Aru Islands, Indonesia are lacking despite frequent collection
for the live reptile trade (Pernetta 2009), and all that has been
published on its occurrence to date appears to have originated
through second-hand sources. Bennett (1995, 1998) reported
that V. beccarii occurs in mangrove swamps whereas Sprackland
(2009) claims that it inhabits lowland wet forests and swamps.
Like all other members of the V. prasinus complex, V. beccarii is
indeed highly specialized morphologically for an arboreal life-
style (Greene 1986, 2004), and behavioral observations of V. bec-
carii in captivity further suggest that it is a skilled tree-dweller
(Hartdegen et al. 1999, 2000; Krebs, pers. comm; pers. obs.).
Dietary studies indicate that members of the Varanus pra-
sinus complex feed predominantly on arboreal arthropods
(Greene 1986; Irwin 1994). Though not recovered from the single
V. beccarii stomach analyzed by Greene (1986), we suspect that
the soft-bodied larvae of some wood-boring beetles and bark-
dwelling caterpillars may make appropriate prey items for this
particular foraging behavior in the wild. During experimental
fIg. 4. Female V. beccarii using forearms to extract mouse parts from a hole in a diago-
nally-oriented tree limb.
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Herpetological Review 42(3), 2011
ARTICLES 347
trials, soft-bodied prey such as neonatal mice and Achroia grisel-
la larvae (but also more rigidly-bodied prey such as Zophobas
morio larvae and Nauphoeta cinerea) were easily extracted from
tree holes when impaled by the claws. The sharp foreclaws and
reaching forearm movements of V. beccarii may also be useful
for retrieving nocturnal geckos, tree frogs, and insects that seek
refuge in tree holes and crevices by day.
When compared to other monitor lizards, members of the
Varanus prasinus complex may possess the longest and slender-
est forelimbs in relation to body size (compare drawings by Bel-
lairs 1969). The long and slender forelimbs and elongated digits
of V. beccarii clearly compliment tree hole extractive foraging
well, and allow individuals to deeply penetrate narrow openings
all the way up to the shoulder. This ability should enable V. bec-
carii to exploit an ecological niche that may not be utilized by
many other predators within its range, and can potentially di-
versify the number of different prey items taken, maximizing the
total number of foraging opportunities.
Comparisons of arboreal foraging in Varanus.—Limited ob-
servations on arboreal species in the field prevent a thorough
analysis of tree hole foraging tactics used by monitors. However,
field observations on the foraging habits of Varanus glauerti in
northern Australia (Sweet 1999) enable direct comparisons be-
tween V. beccarii and this similar-sized arboreal species. Like V.
beccarii, V. glauerti will also seek out hidden prey within holes
and crevices in trees (Sweet 1999); however, the strategies em-
ployed by each to retrieve prey from narrow openings are mark-
edly different. Once a prey item is discovered inside a tree hole
that is too small to enter with the head, V. glauerti will attempt to
widen the diameter of the opening by clawing at it margins until
it is large enough for the head to enter, where the prey can then
be seized with the jaws (Sweet 1999). Although captive V. beccarii
will also enter holes to subdue prey if large enough for the head
(pers. obs.), its use of the forelimbs to extract prey from smaller
openings rather than attempting to widen them, distinguishes it
behaviorally from V. glauerti as well as all other monitor lizards,
as currently understood.
Forelimb-assisted prey extraction in additional taxa?—Given
that several monitor species occur in forested environments
and might have arboreal habits and diets similar to those of
Varanus beccarii, it is possible that forelimb-assisted extractive
foraging might be used by additional taxa. Given their related-
ness, and the near-identical similarities in size, morphology,
diet, and arboreality between V. beccarii and other members of
the V. prasinus complex (Greene 1986; Sprackland 1991; Ziegler
et al. 2007), we suspect that this behavior is also used by other
members of the complex. Notably, Irwin (1996) reported see-
ing a wild V. keithhornei, sister taxon to V. beccarii (Ziegler et al.
2007), “on the ground scratching with its forefeet in a rotting log,
obviously foraging for food.” Whether this observation refers to
the same prey extraction behavior reported here for V. beccarii is
unclear; however, it necessitates the need for further investiga-
tion of forelimb-assisted extractive foraging in the V. prasinus
complex.
It might seem obvious that the skilled forelimb movements
described here for Varanus beccarii represent a specific behav-
ioral adaptation for use in trees. However, we cannot rule out
the possibility that this foraging behavior might also occur in
terrestrial species. The ability to extract prey from rock crevices,
tree stumps and felled trunks, burrows, and other narrow open-
ings would benefit the foraging efficiency of terrestrial moni-
tors. Indeed, some terrestrial species have developed unique
and insightful methods of extracting prey from rock crevices
and burrows using coordinated tail movements (Eidenmüller
1993; Gaulke 1989; Horn 1999). Use of the forelimbs in similar
situations can be equally useful for extracting prey, and is per-
haps more feasible from a developmental standpoint given that
many species are known to use the forelimbs in various capaci-
ties while foraging (e.g., Auffenberg 1981, 1988, 1994; Blamires
2004) or handling and fragmenting prey (e.g., Auffenberg 1981;
Hartdegen et al. 2000; Horn 1999; Kiehlmann 1999; Krebs 1979,
2007, pers. comm.; Stanner 2010).
Implications for future research.—Arboreal species offer
unique opportunities for studying the insight and behavioral
complexity of monitors, particularly because they inhabit com-
plex, three-dimensional environments (Greene 2004) and may
require more advanced processing skills and finer motor coor-
dination than comparatively-sized terrestrial species. Studies
on several mammalian groups have shown that brain sizes are
positively correlated with arboreality (Budeau and Verts 1986;
Eisenberg and Wilson 1981; Meier 1983). Because monitors
vary considerably in habit from strictly terrestrial to largely ar-
boreal, and share many ecological and physiological affinities
with mammals (Wood et al. 1977; Horn and Visser 1997; Sweet
and Pianka 2007), it is of interest whether selective pressures
have favored a similar evolutionary trend in monitors. Surpris-
ingly, the only direct study to compare relative brain sizes in
monitors focused solely on the ecologically-dissimilar Varanus
salvator complex and V. glebopalma, but did note distinct mor-
phological differences between the two (Andres et al. 1999).
Similar comparative studies on monitor brain sizes which sam-
ple a greater diversity of taxa can provide a framework for un-
derstanding the evolution of encephalization and intelligence
within the genus.
Further investigations of skilled forelimb movements and ex-
tractive foraging in monitor lizards are planned. When applied
to current phylogenies (Ast 2001; Fitch et al. 2006; Ziegler et al.
2007), confirmed usage of this behavior by additional taxa can
allude to the evolution of skilled forelimb movements in moni-
tor lizards, but more broadly in tetrapods as well (Iwaniuk and
Whishaw 2000). Additionally, observations of forelimb-assisted
extractive foraging in the field can yield important details about
its usage and importance to wild monitor populations which
cannot be inferred from captivity.
Finally, our observations have important implications for the
management of Varanus beccarii in captivity. Given the impor-
tance of enrichment stimuli in the husbandry of monitor lizards
(Burghardt et al. 2002; Manrod et al. 2008; Sunter 2008), replicat-
ing or modifying the drilled tree trunks described in this report
and using them during feedings can provide a valuable source
of behavioral enrichment for captive individuals. All specimens
tested in the present study continue to show interest in the
drilled tree trunks within their terraria, stopping to investigate
holes and crevices as they are encountered through daily forag-
ing activity. Such an apparatus can potentially increase activity,
reduce boredom and stereotypic behaviors, and improve the
overall quality of life for specimens of V. beccarii and possibly
other members of the V. prasinus complex maintained in zoos
and other captive situations.
We welcome correspondence and encourage feedback from
zoos, researchers, and private keepers working with monitor liz-
ards on the subjects of extractive foraging and skilled forelimb
movements, as well as additional behavioral specializations in
Varanus.

Herpetological Review 42(3), 2011
348 ARTICLES
Acknowledgments.—We thank Sam Sweet for testing his captive
specimen and for sharing observations and photographs. We also
appreciate helpful discussions and constructive comments on ear-
lier drafts of this manuscript by Uwe Krebs, Michael Cota, and two
reviewers.
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Urban Students and Urban Serpents: The Eects of Hands-on
Learning in Student Perception of Snakes
Snakes and teenagers share a common negative stereotype
and are often maligned or feared because of this reputation.
Here, I present observations and an analysis of shifts in high
school students’ perceptions of snakes after completing an in-
tensive eight-week course, including participation in field stud-
ies of urban garter snakes. These observations support the inclu-
sion of such experiential and in-depth programs in schools as
means both to teach science and foster understanding and ap-
preciation of the natural world. Programs providing such oppor-
tunity can work to reverse negative public image of both snakes
and teens.
The involvement of non-scientists in scientific studies and
conservation efforts has recently gained attention as a valu-
able, and even integral, component of such projects (Cooper et
al. 2007). Wildlife education, specifically those programs which
effect attitudinal change, can provide great benefit to conser-
vation efforts and are much needed (Adams and Thomas 1986;
Mitchell and Jung Brown 2008; Wojnowski 2009). Attitudinal
changes toward nature are most effective when they result from
an increase in factual knowledge of the natural world, which in
turn can lead to a more full participation in democratic society
(Hendee 1972), a goal at the core of public education. Addition-
ally, Morgan and Gramann (1989) found that the most effective
strategy to increase knowledge and improve attitudes toward
snakes is a “full-treatment” approach, combining information-
based and experiential activities. Such programs in a variety of
subject areas provide a depth of understanding that promotes
the possibility for positive shifts in attitudes and actions (Hooks
1994). Examples that have successfully integrated education and
conservation can be found from Kenya (Wojnowski 2009) to Tex-
as (Sosa et al. 2010). Such efforts work toward the goals of both
collecting scientific data and developing public empathy toward
native herpetofauna that are likely to be incidentally encoun-
tered by community members.
Snake mythology permeates our culture, often leading to
undue fear and misunderstanding (Gibbons 1983). Public edu-
cation about snakes and the roles they play in a variety of eco-
systems is lacking (Wojnowski 2009) and, when it does occur, is
often conducted by those without proper knowledge themselves
(Gibbons 1983). Recent studies have even postulated that the
human fear of snakes has an evolutionary basis and is not af-
fected by direct experience (LoBue and DeLoache 2008). This
analysis presents evidence to the contrary: that perception of
snakes can shift as a result of educational experiences. Specifi-
cally, hands-on involvement of non-scientists in herpetological
studies serves to increase both empathy and understanding, as
well as benefits the collection of scientific data.
Materials and Methods.—From August to October 2010, I
taught an interdisciplinary and hands-on class, “Snakes & Let-
ters,” at P.S. 1 Charter School in Denver, Colorado, USA. The
eight-week class included curriculum in both science and Eng-
lish and was attended by 28 high school students (age range:
13–19 yrs), though not all students participated for the duration.
The school is racially diverse, with 85% of students categorized
as “high-risk” for not completing high school, as defined by
Colorado law (Colorado General Assembly 2010). Students en-
gaged in lectures, discussions, readings, demonstrations, and
hands-on activities to develop their skills in the areas of scientif-
ic knowledge, use of scientific equipment, experimental design,
ERIC GANGLOFF
Department of Ecology, Evolution and Organismal Biology
Iowa State University
253 Bessey Hall, Ames, Iowa 50011, USA
P.S. 1 Charter School, 1062 Delaware Street, Denver, Colorado 80204, USA
e-mail: ericjganglo@gmail.com