Author(s): Gerald Borgia
Source: American Scientist , NOVEMBER-DECEMBER 1995, Vol. 83, No. 6 (NOVEMBERDECEMBER 1995), pp. 542-547
Published by: Sigma Xi, The Scientific Research Honor Society
Stable URL: https://www.jstor.org/stable/29775558
REFERENCES
Linked references are available on JSTOR for this article:
https://www.jstor.org/stable/29775558?seq=1&cid=pdfreference#references_tab_contents
You may need to log in to JSTOR to access the linked references.
JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide
range of content in a trusted digital archive. We use information technology and tools to increase productivity and
facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]
Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at
is collaborating with JSTOR to digitize, preserve and extend access to American Scientist
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
Why Do Bowerbirds Build Bowers?
Females prefer to visit courtship areas that provide easy avenues
of escape, thereby protecting them from forced copulations
Gerald Borgia
males that might try to force her to
plays and mate, however, have al?
arise from an arbitrary or pre-existing
female preference, such as an attraction
to nest-like structures.
than 30 bowers for a single species
New Guinea clear
decorate and copulate. Bower building could even
Male bowerbirds
ofand
Australia
courts and build bowers at display sites
where they mate. Bowerbird species,
however, differ in several characteris?
tics, including the type and color of
court decorations and the form of a
bower, if one is even built. Moreover,
some male bowerbirds possess bright
crest and body plumages, and others do
not. Charles Darwin’s observations of
satin bowerbirds?in the Blue Moun?
I have used Darwin’s method of
comparisons of related species to re?
construct the evolution of bower build?
ing. My work on several species of
bowerbirds confirms the existence of
female preferences for males with well
tains of Australia during his round-the
built and highly decorated bowers. The
origins of bower building, however,
contributed to the then-controversial
can be best explained as a trait that at?
tracts females because of the protection
world journey on the HMS Beagle?
central element of his theory of sexual
selection called female choice. The high?
ly sculptured structure of a bower and a
male’s use of brightly colored decora?
tions suggested to Darwin that female
bowerbirds might shop for the most at?
tractive bower, thereby directing the
evolution of these display traits.
Nevertheless, several other mecha?
nisms could have driven the evolution
of bowers. The so-called good-genes
model, for instance, suggests that
male-display traits, including bowers,
might indicate a male’s vigor and, ulti?
mately, his quality as a sire. That is,
more vigorous males might have better
bowers. A bower could even directly
benefit a female, perhaps protecting
her from threats, including predators
that might attack her during mating or
Gerald Borgia is professor of zoology a t the
University of Maryland. He holds a long interest in
mate choice, which he studied in insects for his doc?
toral research at the University of Michigan. He
began studying bowerbirds 15 years ago, while he
was a postdoctoral fellow at the University of
Melbourne. This year he and his students will
return to his original bowerbird study site for fur?
ther investigations of how male display affects mate
it provides them from forced copula?
tion by bower owners.
Evaluating Bower-Building Hypotheses
Picking one model of bower-building
evolution over another proves difficult
lowed intensive monitoring of more
through an entire mating season. That
information has provided a direct mea?
surement of male attractiveness and de?
tailed information on how males and fe?
males use a bower during courtship.
For most of the species that my col?
leagues and I have studied, we were the
first to see these bowerbirds perform
successful courtships, which ended in
copulation.
By comparing mitochondrial DNA
sequences, my colleagues, Robert Kus
mierski and Ross Crozier, and I have
developed a highly reliable bowerbird
phylogeny, which shows evolutionary
relationships among species. Our phy?
logeny indicates, in contrast to some
earlier speculation, that all 18 species of
because of several problems. One can?
not always reconstruct what happened
long ago, especially for display behav?
ior that leaves no fossil record. More?
bowerbirds evolved from a single an?
cestral species. Three species branched
over, bower building may have
monogamy with both parents caring
evolved over a period of time, and dif?
ferent stages of its evolution may have
served different functions. Although
experiments can show the plausibility
of a particular evolutionary process,
understanding the origins of traits can
best be accomplished by careful com?
parisons between species whose rela?
tionships are known.
Such an analysis depends on accurate
and detailed descriptions of bowers and
how they are used in courtship in mod?
ern species. Obtaining detailed quantita?
tive information on courtship and mat?
ing through direct observation proves
nearly impossible, because bowers are
separated widely, the mating period may
last several months and a large propor?
tion of males do not or rarely copulate.
choice. Address: Department of Zoology, University
Remote-controlled cameras aimed at
of Maryland, College Park, MD 20742.
bowers where males perform their dis
542 American Scientist, Volume 83
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
off from others long ago, and they em?
ploy the predominant avian pattern of
for their offspring. All other bower?
birds are polygynous (males mate with
more than one female), and they create
elaborately decorated display courts.
All but two of the polygynous species
build bowers. The second major diver?
gence developed between species that
build avenue bowers?two vertical
stick walls, separated by a central av?
enue?and those that build maypole
bowers?sticks woven around a sapling
to create a decorated pillar. It appears
that bower building evolved once and
then diverged into two types of bow?
ers. The two species that do not build
bowers, toothbill and Archbold’s
bowerbirds, apparently lost bower
building behavior, but they do clear
and decorate display courts. Compar?
isons of bowers and relationships
among living species suggest that a
1^
Figure 1. Male bowerbirds build bowers, where they court and mate with females. Some species, such as this satin bowerbird, build avenue
bowers, made of two freestanding stick walls. Others build maypole bowers, in which sticks are placed around a central sapling (Figure 3). In
addition, a male may decorate his bower with a variety of objects, including the pieces of blue plastic shown here. This complex behavior of
building and decorating prompts a fundamental question: How did it evolve?
decorated sapling?similar to a simple
maypole bower?may represent the
ancestral bower type.
Several criteria can be used to evalu?
ate hypotheses for bower evolution
based on mating behavior and the evo?
lutionary relationships among species.
lern solved by a bower. These species
should possess compensatory behav?
iors, which work in the absence of a
bower to protect females from forced
copulations by the courting male.
Avenue-Bower Builders
The group of avenue-bower builders
consists of three genera and eight
species, including the satin bowerbird.
Satins inhabit rain forests along the
To the extent that these criteria are met,
we can identify the likely initial causes
of bower building. First, the proposed
function of incipient bowers should be
consistent with the design of the sup?
posed ancestral bower. That is, the
bower type that appears most consis?
tent with the ancestral bower type
should be capable of functioning in ac?
cordance with the hypothesized cause
of bower origins. Second, the proposed
function of the earliest bowers should
be consistent with the design of mod?
ern bower types. The persistence of
bower building among the polygynous
species suggests that ancestral func?
tions may remain important. If a con?
sistent function exists for modern bow?
ers, it would be a likely candidate for
the ancestral function. Third, species
that do not build bowers should pos?
sess alternative solutions to the prob
Figure 2. Inside an avenue bower, a female satin bowerbird observes a male’s courtship display.
A male flits back and forth across the avenue opening, flicks his wings, mimics the calls of other
birds and performs other displays. When a male runs to the rear entrance of the avenue to mate
with a female, she either waits to copulate or departs through the front opening.
1995 November-December 543
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
eastern fringe of Australia. A male faces the female with a small decora? satin courtships lead to copulation, the
aligns his bower along a north-south tion?usually a yellow leaf?in his most attractive males mate in 25 per?
line, with a display court at the north mouth and performs a series of knee cent of their courtships. The higher rate
end. He decorates his display court bends. After that, he usually moves of courtship success by specific males,
with blue, yellow and white objects in? away from the bower, makes several the significant effect of small decora?
cluding feathers, flowers, leaves, snail harsh calls and then returns to the bow? tions and the fine details of bowers on
shells and, where available, plastic and er for more displaying.
mating success, and the changes in a
female’s behavior that indicate her
paper, over a background of yellow
In courtships that lead to copulation,
straw. The male trims leaves from a female in the bower avenue crouches readiness to mate after she arrives at
above the court, and the northern ori? deeply as courtship progresses, and a the male bower indicate that a female
entation causes the sun to illuminate slight Hfting of her tail signals her will? makes her mating decisions after she
the decorated site, perhaps making it ingness for mating. A male circles arrives at the court.
more attractive. Males of several around to the opposite end of the bow?
species destroy each other’s bowers er and mounts her for a three-second Maypole-Bower Builders
copulation. After mating, a female The other major group of bower
A visiting female usually lands in shakes and flaps her wings in or near builders make maypole bowers?a
cover south of the bower and then the bower for a few minutes before central “pole” surrounded by a circular
and steal decorations.
moves rapidly into the avenue between
leaving. Although a female may visit display court. Some maypole builders
the two stick walls. On the display several bowers, she usually mates with cover part of the display court with a
court, a male makes vocalizations, in? only one male. The average courtship hut-like structure. The simplest struc?
cluding guttural chortles and squeaks lasts about four minutes. If a male ture, however, comes from Macgre
that progress into a typical call se? moves to the southern end of a bower gor’s bowerbird, which lives at high el?
quence: initial mechanical buzzing fol? before the female is ready, she escapes evations in the mountains of central
and eastern New Guinea. It decorates a
lowed by mimicking a kookaburra, a through the northern exit.
Females exert strong preferences in sapling with sticks and moss. This
a crow. During the buzzing, a male mating, and only a small proportion of bower may be most similar to the an?
moves swiftly across the northern bow? males achieve most of the ma tings. cestral one for all bowerbird species.
er entrance and rapidly flicks one or Males with high quality bowers?with A male Macgregor’s bowerbird selects
Lewin’s honeyeater and less frequently
both wings. When he begins mimicking symmetrical walls formed from thin, a thin sapling, usually from three to six
other birds, he stops at one side of the densely packed sticks?and many dec? centimeters in diameter, and surrounds it
bower entrance, puffs up his body orations on their courts mate most of? with horizontal piles of sticks, which in?
feathers, holds his wings at his side,
ten. Although only nine percent of crease the pole’s diameter to about 25
544 American Scientist, Volume 83
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
centimeters. He covers the lower part of
the maypole and the court floor with a
fine compressed-moss mat that rises up
to form a circular rim about 40 centime?
ters from the pole. He decorates the court
with small objects mcluding seeds, and
he hangs regurgitated fruit pulp near the
ends of the maypole sticks. On the
court’s rim and nearby logs, he adds
woody black fungi.
We have observed young male Mac
gregor’s bowerbirds clearing courts
around the naked trunks of small trees.
A selected tree’s diameter usually ap?
proaches that of a fully developed
maypole, which is much larger than
the saplings selected by an adult male.
This shows a functional correspon?
dence between the trees used by young
males and the size of maypoles built
by adults.
A female arriving for courtship on
an adult male’s bower usually lands on
the maypole and then hops down to
the court. The male moves to the oppo?
site side of the maypole with his chest
close to it. He calls, and as the female
moves around the maypole, he makes
a counter move to keep the maypole
between them. Calling, moving and
counter moving go on for one to two
minutes. Then the female stops mov?
ing, and the male expands his bright
Figure 4. Macgregor’s bowerbirds dodge around the maypole during courtship. A male calls, a
female moves around the pole and the male makes a countermove to keep the pole between
them. If a female wants to mate, she stops moving, allowing a male to approach her.
overhanging limbs, making a set of
curtains that crisscross and nearly
touch the display court.
Archbold’s bowerbird courtship be?
gins with a male chasing a court-visit?
ing female. He flies and hops low, close
orange head plume and shakes his
head from side to side, giving the fe?
male a view of rapid orange flashes on
to the court surface, beneath the vine
curtains. After repeated chases, a fe?
male stops moving, apparently signal?
alternating sides of the maypole. While
ing the male that he may approach her.
shaking his head, the male moves to?
ward the female to copulate. In some
cases, the male may charge the female
without prolonged head shaking, caus?
ing her to escape around the opposite
side of the maypole.
Bowerbirds without Bowers
Two species of bowerbirds, toothbill and
Archbold’s, clear and decorate courts,
but they have lost their bower-building
behavior. The unique mating tactics of
each of these species suggest functional
alternatives to bower building.
Archbold’s bowerbird has lost bow?
on limbs that overhang a court. A male
also drapes orchid vines on numerous
the center of an aggregation?the birds
the highest mating success.
the male faces the female and makes a
chattering call, during which he moves
his head rapidly with slight side-to
side movements and occasionally jerks
up his head and tail. If the female re?
mains stationary after that frontal dis?
play, the male moves behind her, stay?
ing near the ground, and then rises
rapidly to perform a brief copulation.
The low position of the male held
throughout courtship, in part assured
by the low-hanging vine curtains, re?
encompasses several small trees, and
their bases are cleaned meticulously.
Unlike other bowerbirds, a toothbill
decorates its court with large objects:
shells, and he places smaller decora?
tions in piles near a court’s edge and
courts than do other species. Males at
female. With his head near the ground,
male decorates his court with beetle
of paradise) head plumes and snail
toothbills spend little time on the
ground and far less time on their
that preliminary studies show to be
dominant in vocal interactions?have
duces his opportunity for forced copu?
lations by jumping on the female.
wings, dark fruit, King of Saxon (a bird
ing them to interact through loud calls.
Dominant males interrupt the calls of
males on adjacent courts. In addition,
The male then presses his body close
to the fern mat and moves toward the
er-building behavior. Instead, it clears a
display court that is about four meters
long and 2.5 meters wide, and it covers
the court with a thick mat of ferns. A
courts, the courts of different males are
aggregated, in a so-called lek, and are
often less than 30 meters apart allow?
Male toothbills clear courts that are
about two meters in diameter. A court
fresh leaves turned upside down so
that their light undersides are showing.
Although not visible from adjacent
Figure 5. Toothbill bowerbirds dear courts but
do not build bowers. A male decorates his
court with large leaves, which he turns upside
down. The rectangular pieces of paper on this
court were added in an experiment to test the
colors of artificial objects males would used.
(Photograph courtesy of the author.)
1995 November-December 545
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
tection of a bower probably attracts fe?
males and increases their visitation,
which more than compensates a male
for losing forced copulations. Given
that female bowerbirds choose the
courts they visit, they should prefer the
ones that provide protection from
forced copulations. A female that freely
chooses her mate should also be less
likely to mate with another male. That
combination of behaviors provides
bower-building males with increased
visitation by females and a high chance
of being a female’s only mate.
In some bowerbird species, males at?
tack visiting females during courtship,
Figure 6. Archbold’s bowerbirds also build bowerless courts. A male approaches a court-visit?
ing female with low-level flights or hops. He also makes calls and jerks his head from side to
side. The female either remains stationary for mating or escapes.
and a bower might protect a female
from such a threat. A maypole bower
could serve that purpose. At avenue
bowers, on the other hand, a male faces
D?ring courting, a female arrives on there is little need for a bower’s pro? a female during courtship, so the bower
tection from forced copulation.
the court and stands still, as if waiting
for a male. After little or no display, the
male aggressively mounts the female. Why Build Bowers?
offers no protection. Moreover, a female
confined inside avenue-bower walls
makes a susceptible target; she could
The longest observed courtship lasted Although avenue and maypole bowers only escape by moving backward, be?
just 3.8 seconds. Toothbill copulation, differ in form, observations of courtship cause the walls prevent her from mov?
however, lasts longer and appears vio? behavior at bowers show that both ing sideways or turning around. If bow?
lent compared with the brief and coop? provide a barrier that protects a visit? ers served originally as protection
erative mating of other bowerbirds. ing female from forced copulations by against aggressive attacks from court?
During mating, a male toothbill makes a courting male. Both avenue- and ing males, the evolution of the avenue
low buzzing calls and beats his wings. maypole-building males perform pro? bowers would require the loss of that
After mating, a female leaves immedi? longed and active courtship displays. function and replacement with others.
ately. The use of exceptionally loud A male watches a female until she sig? Although the prostrate position taken
calls and large decorations and evi? nals her readiness for mating, then he by a courting male Archbold’s may pro?
dence of a female preference for cen? moves behind her to copulate. A fe? vide protection from attacks, no such
tral males on leks suggests that tooth? male not prepared to mate can escape behavior has been observed in tooth
bill females may assess males before while an approaching male moves bills. Overall, it seems unlikely that
arriving on the court. If a female choos? around a barrier created by a bower bowers initially evolved to protect fe?
es a mate before arriving on a court, wall or maypole. A bower also allows males from attacks by males.
a female to observe court decorations
The good-genes hypothesis gains
from close range with a reduced threat support from some observations, in?
of forced copulation. The freedom from
forced copulation offered by the bower
may explain the high degree of elabo?
cluding the tendency of females to
choose vigorous males and the intense,
athletic displays of males in species
ration of the decorated ground that has with widely separated bowers. These
evolved in this group, including the characteristics, however, may derive
use of small decorations on a ground from the origins of male courtship
“dances” and vocal behavior rather
court.
The two species that build courts
than from bower building. In some
without bowers offer alternative solu?
modern species, a female might assess
tions to the problem of restricted mate
a male’s genetic quality from his ability
to maintain his bower in the face of de?
choice because of forced copulation.
Toothbill females select desirable mates
before arriving on a court, so they do
not need the protection of a bower. The
low position of an Archbold’s bower?
Figure 7. Great bowerbirds build avenue bird male while courting allows a fe?
bowers and decorate them with green objects male to escape an unwanted copulation.
Males of many species gain repro?
and shells. A male great bowerbird organizes
the decorations strategically, such that they ductive success through forced copu?
contrast with his lilac crest during his dis? lation, so why would male bowerbirds
play. The combination of decorations and build a structure that limits their op?
behavior may enhance a female’s interest
portunities for this behavior? The pro
B. Chudleigh, Vireo
546 American Scientist, Volume 83
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
struction by rivals, but such a process
seems unlikely early in the evolution
of bower building, when only a few
males had bowers. Assessing male
quality by his bower probably arose as
a secondary function after bower
building evolved.
The so-called runaway model sug?
gests that female preferences and male
traits evolve together, driven by a mating
advantage gained by males that possess
an extreme version of a trait, such as
Once the tendency toward stick bowerbirds with simple or no bowers,
bower building. No evidence, though, built bowers evolved, two trends could the position of males and females
suggests that males with large bowers emerge. First, bower form could diver? varies during displays, and for females
mate more. In addition, recent versions
sify to serve other functions. Second, to see bright colors males must carry
of the runaway model expect high costs free-standing stick barriers would al? bright plumage. In bowerbirds with
for a trait that confers a strong mating low males even more freedom in se? more complex bowers, which focus a
advantage. In an intense study of satin lecting bower sites and in concentrat? female’s attention on concentrations of
bowerbirds, I found no evidence of high
cost, despite strong effects of bower qual?
ity on male mating success.
Several other hypotheses also lack
ing decorations in advantageous decorations, costly bright plumage
locations. The transition to avenue may be replaced by strategically locat?
bowers required losing the use of a ed arrays of decorations.
sapling as a bower support and the ad?
The combination of analyzing bower?
support. The predation hypothesis dition of a different barrier. The two bird behavior and constructing a phy
seems unlikely, in part, because no ex? walled barrier oriented a female to? logeny produces an unexpectedly co?
ample of predation on females or ward parts of a court where a male herent picture of bower function,
males appeared during more than could concentrate his decorations on a despite the diversity in structural
100,000 hours of monitoring bowerbird well-lit stage and arrange the decora?
display courts in 10 species. That result
tions to his best advantage. Many av?
form. All types of bowerbird behavior
indicate that females seek protection
proves especially relevant given that enue-building males separate decora? from unwanted mating. No other hy?
males of most species are not protected tion types in zones around a bower in pothesis proves consistent with current
from predators during courtship. In an apparently functional manner. Male bower function, the function of a pre?
addition, neither major bower type avenue-building great bowerbirds, for sumed ancestral bower and novel be?
protects a female from behind, where a example, place green objects beneath havior in derived bowerless species.
predator or a marauding male seeking the spot where they display their lilac The significance of protection from a
forced copulation might approach.
crest. The decorations are a comple? courting male suggests an important
mentary color to a male’s crest and role for models that predict direct ben?
Evolution of Bower Building
probably increase the contrast of his efits that females might gain from elab?
Determining the evolution of many display. The hut-like cover on some orate male traits.
traits requires an explanation of how maypole-bower courts also orients a fe?
incipient stages could be used. Our male to a male’s display.
Acknowledgments
No one knows whether bower This research was supported by the Na?
work suggests that the first bowers
consisted of a sapling on a display building or decorating came first, but it tional Science Foundation and the Univer?
appears that the development of com? sity of Maryland. The New South Wales
plex bowers may have strongly influ? and Queensland National Parks, The Aus?
on his display court over ones with enced the use of decorations and the tralian Bird and Bat Banding Scheme, and
other attractive attributes that might evolution of male plumage. The late E. the PNG Wildlife and Conservation De?
benefit her or her offspring? Maybe fe? Thomas Gilliard of the American Mu? partment provided permits. R. Crozier, }.
court. If that is correct, why might a fe?
male prefer a male that has a sapling
seum of Natural History argued that Dimuda, G. Harrington, I.,]., N. and M.
the degree of male head-crest elabora? Hayes, J. Lauridsen, M. J. Littlejohn, J.
sapling, could separate a female from a
tion correlates inversely with bower Kikkawa, M. Raga,}. Hook, and M. and }.
courting male and allow her to closely size and the number of decorations in Turnbull provided important support. C.
observe the male’s display and deco? maypole bowers. He suggested that Depkin, D. Bond, K. Collis, R. Condit, A.
rations without committing to mating. plumage characteristics were trans? Day, }. Helms, L Kaatz, C. Loffredo, }.
By placing sticks around a sapling a ferred to the bower and its decorations, Morales and D. Sejkora participated as
males simply sought protected courts.
A court with a natural barrier, such as a
male would be less constrained by
but offered no explanation for the
sapling size and location. He could uti? transfer.
lize a much wider range of saplings
Observations of how bower shape
and ones in particularly suitable loca? constrains a male’s display may reveal
tions, by enhancing the diameter of a a relationship between plumage, bow?
maypole to an appropriate size with a ers and display areas. Around the sim?
stick covering. In addition, the soft ple maypole of Macgregor’s bower?
edge created by a stick maypole allows birds or the large bowerless court of
males and females to observe each oth? Archbold’s bowerbirds, decorations
er and anticipate each other’s moves, are spread widely around the bower.
which would be more difficult around The males of both species possess well
a tree of equal diameter. In this sce? developed crests, which they use ac?
nario, stick-built bowers would have tively during displays. That behavior
been an improvement on a previous contrasts with most avenue builders,
practice of using natural barriers on which have either a reduced or no crest
courts. It might have begun with the and build more complex bowers that
rearrangement of fallen sticks that orient a female toward a more limited
were already present to enhance a area where decorations can be concen?
court’s protective qualities and led to a trated and kept in her view. In most
simple maypole bower.
polygynous avian species, including
team leaders and/or co-investigators. More
than 100 volunteers provided excellent field
assistance.
Bibliography
Borgia, G. 1995. Threat reduction as a cause of
differences in bower architecture, bower
decoration and male display in two closely
related bowerbirds Chlamydera nuchalis and
C. maculata. Emu 95:1-12.
Borgia, G. 1985. Bowers as markers of male
quality. Test of a hypothesis. Animal Behavior
35-266-271.
Borgia, Gv and U. Mueller. 1992. Bower destruc?
tion, decoration stealing, and female choice
in the spotted bowerbird (Chlamydera macu?
late). Emu 92:11-18.
Kusmierski, R., G. Borgia, R. Crozier and B.
Chan. 1993. Molecular information on
bowerbird phylogeny and the evolution of
exaggerated male characters, journal of Evo?
lutionary Biology 6:737-752.
1995 November-December 547
This content downloaded from
73.152.85.224 on Thu, 02 Jun 2022 17:30:10 UTC
All use subject to https://about.jstor.org/terms
Presentation on Animal Case Study
CONS 472: Introduction to Animal Behavior
100 points
This is your David Attenborough moment! Each student will have the opportunity to research
and present an animal case study pertaining to the particular topic(s) of each class session. The
animal case study chosen can be a particular species or set of species or a particular taxon (e.g.
amphibians, sharks, etc).
You will give your presentation to the class using some type of visual presentation (e.g.
PowerPoint slides) – but keep them brief and simple. You should give an explanation of the
species/taxon and the particular behavior or set of behaviors, and how it relates/connects to the
daily session’s topic. You should also give examples of how this behavior is currently being
studied, where, and what new technologies (if any) are being used. Finally, you should relate the
behavior to questions of conservation; in other words, how would studying this behavior (in the
wild and/or captivity) provide information to help in conservation actions for this species or their
ecosystem?
Your presentation is meant to be interactive and engage your classmates in discussion. You are
welcome to use as many resources and media sources during your presentation as you would
like, including videos, blogs, StoryMaps, and podcasts (see examples below). (If you choose a
podcast, try to aim for something 15 minutes or less in length). The total amount of time you
should plan to spend on your presentation and discussion with classmates should be about 45-50
minutes.
Animal Case Study Presentation Grading Rubric (100 pts):
Content meaningful, accurate, related to topic: 60 pts
Creative, varied use of media, engagement with peers in discussion: 40 pts
Here are several examples of online media/resources to get you started:
Video: Sea turtles, National Geographic (~4mins):
Blog: SeeTurtles.org blog: https://www.seeturtles.org/turtle-blog
StoryMap: Sea Turtle Science Series:
Podcast: Mote Marine Aquarium: https://mote.org/podcasts/item/where-do-baby-turtles-comefrom-sea-turtle-mating-systems
Whale
Sharks
Subtitle
Let’s start with a quiz!
• On your web browser, go
to: kahoot.it
• Or use the app if you
have it!
Sharks
• Fish with cartilaginous skeleton
• Chondrichthyes:
• Elasmobranchii = sharks, rays, skates,
sawfish
• Holocephali = chimaeras
• 5-7 gill slits on sides of head
• Most sharks are carnivorous
• Some are plankton feeders…
Whale sharks (Rhincodon typus)
• The largest shark and largest fish in the
world!
• Average 6-7.5 m (20-25 ft); adults can
be up to 12 m (40 ft) in length
Worldwide in tropical Atlantic, Pacific
and Indian oceans
Slow moving
Plankton feeders (along with basking
sharks and megamouth sharks)
Mouth at tip of nose or snout (rostrum)
Feed by “cross-flow filtration”
• BBC Planet Earth:
National Geographic:
“Species” Podcast by Macken Murphy: (start at 3 mins)
https://www.mackenmurphy.org/species/episode/2b474
dbb/whale-shark
Whale Shark Conservation
• Endangered on IUCN Red List
• Threats:
• Fisheries catches
• Bycatch in nets
• Vessel/Ship strikes
• Ingestion of marine debris/plastics
Whale Shark Conservation
• Citizen Science:
• Photo ID book: Wildbook for Whale
Sharks (sharkbook.ai) to catalog 20
hot spots around the world
• StoryMap (Galapagos Nat’l Park
Expedition):
https://storymaps.arcgis.com/stories/a
419083caa7a4a9d94f2c10b36a9e3d5
Purchase answer to see full
attachment
