Predation Adaptions

Predation Adaptations

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Ecology - Predation Adaptions

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Ingrid Schoonover
March 7, 2021
Part 1- Examples of crypsis and camouflage used by prey organisms to
avoid detection by predators.
Example 1: Uroplatus genus
The genus Uroplatus compromises several species of leaf-tailed or mossy-looking geckos that are
endemic to Madagascar. The species in this genus are nocturnal and thus need defenses from their
predators (birds, snakes, rats) during the day while they sleep. The adaptation that they possess to avoid
detection is to camouflage by looking like moss, lichen, bark, or leaves. The specific morphology differs
by species, with some species like Uroplatus sikorae and Uroplatus henkeli looking like moss/lichen,
where other species such as Uroplatus phantasticus look like leaves.
Uroplatus sikorae are morphologically shaped to mimic their environment, and they even have fringes
and flaps of skin that help them look more natural in their environments. They can also change the color
of their skin to blend in with their surroundings. They will also flatten themselves against their
environment to increase the effectiveness of this disguise.
Uroplatus phantasticus have a notched tail that looks like a leaf, and they have fake leaf-veins on their
Example 2: Stick Insects (Phasmids)
Stick insects or phasmids belong to the order Phasmatodea which contains 3000 species of stick insects.
They get their name because they are camouflaged as plants and match their host plant. Some phasmids
are disguised as green leaves with fake leaf-veins, and others have elongated bodies and legs to
resemble twigs or sticks. Their appearance is variable, some are brown, and some are green, they can be
textured with projections to help resemble the host plant, or they can be smooth. They are nutrient rich
and thus eaten by birds, rodents, reptiles, and bats. However, this is a very effective defense strategy
against the visual hunters which allows them to hide on trees in plain sight. Their camouflage does not
work on bats because they use echolocation to find the stick insects. Additionally, some species have
behavioral adaptions such as swaying side to side to mimic a stick blowing in the wind, and others will
use bad-smelling or blinding chemicals if disturbed.
Example 3: Cryptic frogs such as Pseudophilautus cavirostris and Theloderma corticale
Many species of frogs have cryptic or camouflaged morphological adaptations, this allows them to avoid
predators while they are sleeping, feeding, or calling for mates.
The Hollow-Snouted Shrub Frog (Pseudophilautus cavirostris) is endemic to Sri Lanka and is camouflaged
to look like lichen while it sits on bark. They are greenish in color, but mottled with grey and brown, so
they avoid walking across white areas of lichen where they would stand out. To assist in their
camouflage, they have fringed skin on their limbs and body which is textured like lichen. Due to their
camouflage they avoid predation by snakes, fish, and birds.
The Vietnamese Mossy Frog (Theloderma corticale) has green coloration with patches of red or brown
too to help it camouflage as moss, they also have modified textured skin with spines and tubercles.
They have adhesive toes so they will stick to the walls of mossy caves, wood, mossy stream banks, rock
crevices, and floating plants. The flatten their bodies to blend in better and just sit there very still which
makes it hard for their predators (amphibians, reptiles, tree-dwelling mammals) to detect them. They
can also throw their voice into the distance to make it harder for predators to locate them. As a last
resort they will curl into a ball and pretend to be a ball of moss.
Part 2- Examples of physical defenses used by prey organisms to
interfere with handling by predators.
Example 1: Autonomy in geckos
Many geckos have a physical defense against predators called autonomy, which allows them to shed or
drop a body part in response to predator threats. The predator is distracted by this process and it can
allow the prey to get away.
Crested geckos (Correlophus ciliatus) which are native to New Caledonia are often predated on by birds,
bats, larger geckos, and introduced predators such as rats, cats, and fire ants. When threatened by a
predator they will exhibit caudal autonomy and drop their tails. This works because the tail bone has
fractures which allows tail to break off in a smaller segment, and they cut off blood flow (via
vasoconstriction) so they don’t bleed to death. The detached tail will move for several minutes after
being dropped which distracts the predator and allows the geckos to escape. Unfortunately, crested
geckos do not have the ability to regrow their tails, but many other species can regenerate them.
An even stranger example is the phenomena of integumentary autonomy, or the dropping/shedding of
the skin and scales. This physical defense can be observed in four species of the genus Geckolepis – a
group of fish scaled geckos found in Madagascar that will lose their scales as a defense mechanism. One
example is the recently discovered Geckolepis megolepis, when a predator grabs them, they will spin
and rip away the skin (epidermis, connective tissue, and fat tissue) , which distracts the predator and
allows the gecko to escape. Their skin is designed to split in this specific way by tearing in a specific
region, and they can regrow the scales in 2 to 3 weeks. This has been observed in action when
Geckolepis has been attacked by scorpions, birds, and other gecko species, and when caught by humans.
Example 2: Urticating hairs in Neotropical New World Tarantulas (Theraphosidae)
Many of the New World tarantulas (such as within the genus Brachypelma) have specialized urticating
setae that they can flick towards vertebrate predators or use to protect themselves from parasites and
invertebrate predators when molting.
Hair flicking allows for long-range protection from predators when disturbed, they will use spines on
their leg to remove the hair from their bodies and disperse them into the air toward the predator. The
urticating setae or urticating hair is shaped to maximize pain and irritation, they have a penetrating tip
and harpoon-like structures along the hair that cause pain if it gets into the eye or skin and causes
severe respiratory problems if inhaled. This allows the tarantulas to escape from the predators (such as
mammals, birds, etc.).
There are seven different types of urticating setae that tarantulas can have, many species have multiple
One of the more specialized types of setae is type VII which works through direct contact, this is
observed in tarantulas within the genus Kankuamo, this defense works when they press the setae into a
predator that approaches them with the intention of attack.
Other species such as Theraphosa blondi and Lasidora sp. will also attach type I urticating setae to the
silk that they use for molting webs and egg sacs, which deters smaller invertebrates like parasitic fly
larvae (phorid flies parasitize tarantula eggs) and ants.
Example 3: Mobbing behavior in birds
Mobbing is an example of physical defense that is seen in many species of birds, where smaller birds will
join and mob a larger predator such as a bird, snake, cat, or fox. They do this to drive away birds that
they think are dangerous for the purpose of defending themselves, their territory, their food sources, or
their nests and offspring. Mobbing works by the birds making alarm calls while striking or chasing the
predator, these predators usually rely on the element of surprise to catch their prey so by revealing their
location they lose this advantage and can often be deterred by this behavior. Some species that will
commonly mob include sparrows, brewer’s blackbirds, chickadees, jays, grackles, gulls, and crows.
Part 3- Examples of aposematic coloration.
Example 1: Bright warning colors and threat displays in Poecilotheria tarantulas.
The genus Poecilotheria includes species of highly venomous and nasty tarantulas that are native to the
forests of India and Sri Lanka. They are very large arboreal tree tarantulas that when threatened they
will stand on rear legs and raises front legs and pedipalps and bares fangs, this reveals their very colorful
under legs and mouth, which are usually colored bright yellow or orange, an indicator of their potent
venom that is capable of killing many animals and causing severe and long-lasting pain in humans. This
display warns predators to leave them alone because they will strike if they need to.
Example 2: Red Velvet Ant (Dasymutilla occidentalis)
The Red Velvet Ant (Dasymutilla occidentalis) is a colorful red and black wasp, with a stinger half the
length of their body that is capable of injecting venom that causes a very painful and intense sting. It is
the wingless females that are dangerous, but not the males. These bright contrasting red and black
colors are warnings to predator and serve to reinforce the warning that they should not be messed with.
Insectivorous lizards learn to avoid these aposematic colored velvet ants in feeding trials, because they
do not want the intense burning or shocking feelings that result from their stings. In the wild lizards
rarely feed on velvet ants, which shows that this is an effective defensive strategy.
Example 3: Skunks
Skunks have black and white contrasting warning colors that signal danger to their predators, because if
they get too close, they will be sprayed with noxious stinky chemicals from their anal glands. The bold
stripes on their body point to their anal glands which reinforces the message of this display. Predators
include owls, foxes, bears, coyotes, mountain lions, and bobcats. And all of them (except the owl
because they can catch them before getting sprayed) learn not to mess with skunks, because if they get
sprayed then the smell will make it hard for them to find food because prey items will smell the scent.
An experiment by Jennifer Hunter at UC Davis proved the effectiveness of this defense mechanism. She
put stuffed skunk taxidermy mounts at 10 locations in California where skunks were present or absent
and then with cameras watched how predators such as bears, mountain lions, coyotes, and bobcats
interacted with the mounts. In the areas where skunks were not naturally present the predators
interacted with the mounts by approaching them, licking them, and dragging them away. But in the
locations that had naturally occurring skunk populations the predators would avoid the mounts because
they recognize the aposematic colorations and the message they carry.
Part 4A- Examples of Batesian Mimicry
Example 1: A jumping spider (Phiddipus apacheanus) that mimics western velvet ants
Phiddipus apacheanus is a species of jumping spider in the southwestern United States that mimics the
western velvet ant (Dasymutilla flammifera). The model species D. flammifera, is aposematically colored
with a reddish-orange body and black appendages, these contrasting colors serve as a warning to
predators, because this ant is actually a species of wasp that delivers a very painful sting. The predators
that had a negative experience with this color combination might learn to avoid them, and this antipredator defense is what the mimic species (P. apacheanus) takes advantage of. Adult male P.
apacheanus has the same aposematic color scheme as the velvet ant with a reddish-orange dorsal area
and black appendages, and the front of the spider is shaped to match the edge of the velvet ant’s
thorax. However, this aposematic display is a lie, these do not have a painful sting, but still predators
such as frogs, lizards, birds, mantis, and wasps might avoid them which is beneficial to the spider. G. B.
Edwards put this hypothesis to the test when he designed an experiment where the mimic and model
were exposed to two species of insectivorous lizard to test if both aposematic displays worked. The
lizards did not eat the ant nor the spider, which promotes the hypothesis that the jumping spider mimic
benefits when lizards have had a negative experience with a velvet ant and learned to not eat it because
of the aposematic colors.
Example 2: A fish that looks like a flat worm
Longfin Batfish (Platax pinnatus) are powerful and fast as adults and are semi-protected in their schools.
The juveniles are often called dusky batfish and in contrast to the adults, they are solitary, small, and
vulnerable prey to larger marine predators. They get their name from their dark black body, which is
contrasted to an orange stripe that goes along the edges of their long flowing fins.
They have evolved to look this way because they are Batesian mimics that base their model on the
orange-margined marine flatworm (Pseudobiceros periculosus) that shares the same geographic range in
Indo-Pacific tropical reefs. This flatworm is poisonous and tastes bad and they are consequentially
avoided by predatory fish. The dusky batfish also has behavioral adaptations to aid in this mimicry, such
as undulating their fins to look like a worm and swimming sideways to look flat like the worms. Thus, by
mimicking the unpalatable flatworm, the dusky batfish juveniles are able to avoid predators.
Example 3: Scarlet kingsnake mimicking the eastern coral snake
The scarlet kingsnake (Lampripeltis elapsoides) is a nonvenomous colubrid that is found in the
southeastern United States. They are typically colored with repeating bands of red, black, and whitish
In the more coastal areas where the scarlet kingsnake lives sympatricly with eastern coral snakes they
will adopt the same aposematic display and by appearing venomous are avoided by predators. These
mimics look different than the inland populations that live beyond the range of the coral snake, instead
they have more black, less red, and yellowish bands instead of yellow.
These morphological differences can be explained by the fact that the eastern coral snake’s aposematic
display consists of repeating segments of wide black and red bands that are separated by thinner yellow
bands, which serves as a warning to the fact that they are highly venomous. The scarlet snake mimic
benefits in this situation because they don’t need to make the costly venomous chemicals that reinforce
the display but is still avoided by predators. Support for this hypothesis comes from three things: 1) the
proportion of the dorsal area that is black and red is matched much more closely to the model when
they share the same range versus when the model is not present, 2) predators are more likely to attack
the scarlet kingsnakes when there are no dangerous model coral snakes living sympatricly in the
environment, and 3) a study done by Rabosky concluded that there are many species that mimic coral
snakes with red and black bands.
Part 4B- Examples of Mullerian Mimicry
Example 1: Shared aposematic display by the milkweed beetle, large milkweed bug, and
the small milkweed bug.
The milkweed beetle, large milkweed bug, and small milkweed bug are three species of insect from
different genus that are all toxic and display orange-red and black aposematic color displays.
They have sucking needle-like mouthparts that they use to feed on the sap of the milkweed plant, and
they sequester and store distasteful cardiac glycosides that they use against predators, which are stolen
from the plant’s latex-defense. By all displaying similar aposematic colors they reinforce a powerful
warning sign to the predator that teaches them to avoid these foul-tasting insects, because when there
is more Mullerian mimics then the aposematic display is more effective because the predators would be
more likely to sample one of them and associate the negative experiences with the color. They are the
most morphologically similar in their nymph stage but still look similar as adults. A study with wolf
spiders food preferences revealed that the spiders they recognized milkweed bugs and avoided them,
which is evidence to the effectiveness of the display.
From left to right: Milkweed Beetle (Tetraopes tetrophthalmus), Large milkweed bug (Oncopeltus
fasciatus), and Small Milkweed Bug (Lygaeus kalmii).

Example 2: Mullerian mimicry rings within the velvet ant genus Dasymutilla
In North America there are many species in the genus Dasymutilla (Velvet Ants) that form distinct
groups of morphologically and geographically distinct Mullerian mimicry rings. This genus consists of
diurnal velvet ants where the females have aposematic colorations. The species within each Mullerian
ring share the same aposematic colorations, and they all share the same defensive and painful sting. The
shared color and pattern within velvet ant mimicry rings effectively reduces predation by lizards because
they learn via positive reinforcement of the large sample size to avoid interacting with any of these
species. One study found that 65 species of Velvet ants form 6 mimicry rings in North America: a
western mimicry ring, an eastern mimicry ring, a tropical mimicry ring, a Texan mimicry ring, a desert
mimicry ring, and a madrean mimicry ring.
Example 3: Mullerian orange and black aposematic coloration in toxic beetle and moth
Two completely different species, the lichen moth (Lycomorpha pholus) and the net-wing beetles in the
family Lycidae, display the same aposematic color scheme with black and orange wings, which functions
as a warning display to predators that they are unpalatable due to their chemicals. For example, the
diagram below shows a lycid beetle on the left (a) and the lichen moth on the right (b), they were both
found in the same region of southern Ontario Canada during the same time of year and with the same
contrasting orange and black colors. Species with these displays are sometimes referred to as Lycid
Lichen Moth (Lycomorpha pholus) is a species of arctiid moth have wings that are divided into a lower
black region and an upper orange region. The larvae of this moth feed on lichen which releases lichen
phenolics in defense, the caterpillars store these chemicals and use them for defense against predators
such as birds, wasps, flies, and bats.
Beetles in the family Lycidae are chemically protected by lycidic acid (a type of acetylenic acid), which
makes for a good deterrent against predators such as wolf spiders and orb-weaving spiders that reject
them in experimental setups.
Part 5- Examples of chemicals used by plants for defense.
Example 1: Condensed tannins in Oak Tree Leaves offer defense against Moths
Many species of plants have condensed tannins that have a negative affect on insect growth by binding
to proteins, including digestive enzymes, which reduces the efficiency of nutrient absorption by the
herbivorous predator. These tannins are often bitter in taste which discourages many herbivores from
feeding on the leaves.
The leaves of Quercus robur (Common Oak or English Oak) contain condensed tannins that are produced
by the plant. Some of these condensed tannins including catechin, gallocatechin, and vanillin produced
in the leaves deter winter moth larvae (Operophtera brumata).
Example 2: Lectins as pesticides and NICTABA in tobacco plant leaves
Lectins are carbohydrate-binding glycoproteins that some plant species naturally produced for defense
against nematodes, pathogenic fungi, and herbivorous feeders (especially in the orders of (Lepidoptera,
Coleoptera, Diptera and Hemiptera). Lectins are released (induced) from cellular leaf structures when
disrupted by feeding insects, can be thought of toxic anti-nutrients that bind in the digestive track and
cause serious harm by disrupting the metabolism of lipids, carbohydrates, and proteins in the insect
feeder. Lectins are present in higher concentrations when there are more threats present.
For example: there is a type of Lectin called NICTABA that was discovered in leaves of N. tabacum
tobacco plant leaves that is detrimental to the insects that feed on high concentrations. The damage
caused by chewing insects (cotton leafworm (Spodoptera littoralis), the tobacco hornworm (Manduca
sexta), and two-spotted spider mites (Tetranychus urticae)) induces a response that increases the
expression of NICTABA. Lectin expression is not increased when damage to the plant is caused by
mechanical puncture wounds or phloem-feeding insects such as tobacco aphids and the greenhouse
whitefly that do less damage than leaf chewing insects. Studies have found that NICTABA is highly toxic
to the larvae of the cotton leafworm and tobacco hornworms and reduces their rate of growth and
development after feeding on the tobacco leaves. Increased expression of NICTABA also reduces
damage to leaves after being induced.
Example 3: Salicylic Acid’s role in defending tomato plants from predators
Some plants such as the tomato plant use the plant hormone salicylic acid (a derivative of benzoic acid)
as a line of defense against pests who feed on them. The targets of this defense are the cotton bollworm
(Helicoverpa armigera) and spider mites. When pests feed on them the salicylic acid produces hydrogen
peroxide which damages the digestive system of the pest that ingests it and reduces their growth and
development. Salicylic acid also signals for the release of volatile plant compounds such as HIPV, which
attracts arthropods that will feed on the pest insects.

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