309:, as a last defense . Some example of canid predators are foxes, wolves, or coyotes. Texas Horned Lizards can rapidly increase the blood pressure within the thin-walled sinus of the eye sockets. The sinus walls then break due to increased pressure, sending a spray of blood usually aimed at the mouth or eyes of the predator . The canine will drop a horned lizard after being squirted and attempt to wipe or shake the blood out of its mouth, suggesting the fluid has a foul taste .Studies have identified this as specifically a canid predator defense. In an experiment, canids were less likely to eat Texas horned lizards than other lizard species when presented under the same circumstances . This suggests a learned aversion to horned lizards as prey and is a testament to its evolutionary effectiveness . Although other reptiles use cloacal discharges and external glandular secretions to deter predators, this bizarre example of blood squirting is only observed in three species of horned lizard .
468:. These insects reside on the surface of the water and are attacked from beneath by predatory fish. Experiments varying the group size of the water striders showed that the attack rate per individual water strider decreases as group size increases. However it is important to note that the decrease in attack rate may not be entirely due to the dilution effect. Other predator deterrence effects of group living, as described below, may cause the overall attack rate for the entire group to decrease. If the entire group is attacked less, then it follows that each individual within the group would also be attacked less. Because there are multiple ways group living can help deter predators, whether on a group level or individual level, it is difficult to attribute the decrease in attack rate to just the dilution effect. The dilution effect is just one factor that plays a role in predator deterrence on the level of the individual prey.
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reproductive signaling, and colony defense . The
Malaysian exploding ants are known for a pronounced hypertrophy of their glands and for their novel uses in territorial combat . Simply grasping a worker antâs leg with forceps will cause them to suicidially expel the contents of hypertrophied glands . The adhesives mixed with these compounds may further magnify the effects of the irritant and corrosive irritant aromatic compounds are likely magnified by the adhesives. These sticky substances adhere to their targets and also send signals to additional enemy ants as these arrive to rescue their nest mates .
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heart rate to drop from 155 to 38 beats per minute within one beat of the heart. This drop in heart rate can last up to two minutes, causing the fawn to experience a depressed breathing rate and decrease in all movement called "tonic immobility". Tonic immobility is a reflex response that causes the fawn to enter a low body positioning that simulates the positioning of a dead corpse. Upon discovery of the fawn, the predator loses interest in the "dead" prey. As well, other symptoms of alarm bradycardia including salivation, urination, and defecation can cause the predator to lose interest entirely.
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actually respond by delaying their return. In an experiment by Parejo and colleagues, Eurasian Roller parents approached the nest much more slowly and infrequently if the nest was covered in chick vomit, as opposed to lemon juice . Although
Eruasian Roller chicks arenât intending to call their parents for help, the adults have evolved this reactiveness to their chicksâ danger cues. In this species, parents have learned to stay away when there is danger to benefit their lifetime reproductive success. In other words, this type of predator defense has both direct and indirect benefits.
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282:, a palatable prey species mimics the appearance of another species noxious to predators, thus reducing its risk of being attacked. This form is characteristic in many insects, where harmless species have evolved to imitate the aposematic signal of a harmful species directed at a common predator. Thus, predators that have tried to eat the unpalatable model species will learn to associate its colors and markings with unpleasant taste, learning to avoid the time and energy to catch the model and consequently the mimic. In
622:(an aquatic bird that lives in arctic regions), for example, will vomit a bright orange, oily substance when they feel threatened . The vomit oil of Northern Fulmars (made from fish oils in their aquatic diets) has a deadly effect on predator birds because it will cause their feather to matte, leading to a loss of flying ability and of water repellency . This effect is especially dangerous for aquatic birds because their water repellent feathers protect them from hypothermia when diving for food.
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533:. When stationary, a single zebra stands out in the savannah because of its large size. To reduce this risk of attack, zebras often travel in herds. The striped patterns of all the zebras in the herd confuse the predator, making it harder for the predator to focus in on an individual zebra. Furthermore, when moving rapidly, the zebra stripes create a confusing, flickering movement in the eye of the predator. This also makes a single zebra harder to catch amongst the herd.
401:, which exhibit moonlight avoidance. These nocturnal rodents that usually forage in relatively open habitats and reduce activity outside their nest burrows in response to moonlight. During a full moon, they shift their nocturnal activity towards areas of relatively dense cover. In controlled experiments, artificial moon-like illumination has stimulated similar responses in foraging behavior. This behavioral response is assumed to reduce predation risk.
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as well as maintain the speed for greater distances. Thus, lions tend to attack a prey when its head is down and grouping by ostriches makes it difficult for the lion to determine how long the ostriches' heads will stay down. Thus although individual vigilance decreases, overall vigilance of the group increases with group size and each individual ostrich can spend more time with its head down feeding and still have increased protection.
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461:, often attacks these horses. These flies suck the horse's blood, carry diseases and are most common during specific weeks in the year. During these weeks, the Camargue horses gather in large groups. Though experimental evidence has shown that more flies are attracted to the large groups of horses, each horse has a lower attack rate. Thus, the Camargue horses dilute their individual risk of attack.
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this list . Scientists hypothesize that over time, fish have become aware of the gill-clogging properties of hagfish slime and thus have evolved to avoid them. Because the slime has dramatic effects on the flow and viscosity of water, gills become entangled in the gelatinous substance and most fish that do attempt to capture a hagfish are chocked and will let go within seconds.
155:. These fish have a sharp scalpel-like spine on the front of each of their tail fins. A swipe from a surgeonfish spine can produce a deep cut in a predatorâs flesh. Additionally, the area around the spines is often brightly colored to warn predators of danger. Because of this, predators will often avoid eating the Sohal surgeonfish to prevent injuring itself.
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286:, two aposematic noxious forms conform to the same warning signal in order avoid a common predator. This natural phenomenon of a common warning signal is evident in viceroy and monarch butterflies. In both butterflies, the physical similarities of the wings and their unpleasant taste deter birds from eating both species.
162:, have numerous protuberances and stinging spines along their dorsal surfaces. Studies show that species of limacodid larvae that possess these stinging spines suffer from less predation than the larvae that do not possess the spines. In fact, studies have also shown that one of the limacodidae predators, the
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Many of these advantages decrease the risk of attack for individuals living within the group. The evolutionary advantage of this decreased risk is that the fitness of the individual increases. Thus, even though a larger group may be more susceptible to predators, individuals within the group are less
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of North
America have evolved to eliminate their shadow and blend in with the ground. Their bodies are flattened, with the sides thinning to an edge. The animals habitually press their bodies to the ground and their sides are fringed with white scales, which effectively hide and disrupt any remaining
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Many species use morphological strategies to avoid being detected or consumed by predators. Morphological strategies come in a variety of forms and include both the structure and outward appearance of the animal. The most commonly seen morphological strategy is the use of structural features to deter
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and refers to the idea of reducing the individual's domain of danger. A domain of danger is the area within the group in which the individual is more likely to be attacked by a predator. The center of the group has the lowest domain of danger, so animals will constantly strive to gain this position.
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involves an organism (the mimic) which simulates signal properties of another organism (the model) so that the two are confused by a third living organism and the mimic gains protection, food, mating advantage as a consequence of the confusion. There are two classical examples of defensive mimicry:
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using any combination of materials, coloration, or illumination for concealment, making animals hard to identify by sight. This is common in both terrestrial and marine animals. Camouflage can be achieved in many different ways, such as resemblance to surroundings, disruptive coloration, eliminating
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Thomas Eisner, Tappey H. Jones, Daniel J. Aneshansley, Walter R. Tschinkel, Robert E. Silberglied, Jerrold
Meinwald, Chemistry of defensive secretions of bombardier beetles (Brachinini, Metriini, Ozaenini, Paussini), Journal of Insect Physiology, Volume 23, Issues 11â12, 1977, Pages 1383-1386, ISSN
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in Tsavo
National Park in Kenya, which feed either alone or in groups of up to four birds and are subject to predation by lions. As group size increases, the frequency that each individual raises it head to look for predators decreases. Ostriches are able to run at speeds that exceed those of lions
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nest either solitarily or in colonies. Within the colonies, fieldfares demonstrate communal predator defense by members mobbing and defecating on approaching predators including crows, resulting in reduced predation. In an experiment, artificial nests were egg-bated and placed either near fieldfare
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Another notable defense mechanism can be observed in the primitive hagfish. Slime glands all along the body of a hagfish secrete enormous amounts of âmucusâ when they are provoked or stressed. The common predators of hagfish include seabirds, pinnipeds and cetaceans but most fish are missing from
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chicks also vomit a bright orange, foul smelling liquid when they sense danger. This behavior not only repels prospective predators, but it might also serve as a warning sign to mom and dad that danger is present. Instead of recognizing the vomit as a signal to come help their nest, mom and dad
588:. Goshawks are less successful when attacking larger flocks of wood piegeons than they are when attacking smaller ones. The larger the flock size, the more likely it is that one bird will notice the hawk sooner and fly away. Once one pigeon flies off in alarm, the rest of the pigeons will follow.
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first proposed that group living evolved because it provides benefits to the individual rather than to the group as a whole. The dilution effect supports their proposal because this effect refers to the attack rate per individual rather than attack rate per group. The benefit is to the individual,
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to protect the entire colony. Self-destructive defensive behaviors function to increase the fitness of the entire colony and thus genes for self-sacrificial behaviors are passed from generation to generation . Ants use their exocrine glands and secretions for a number of reasons: communication,
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Individuals within a species often form groups despite the costs of greater competition for resources, risk of infection by pathogens and detection by predators. Yet one of the reasons group living has evolved in nature is because of the benefit this strategy has on predator deterrence. There are
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death to avoid being attacked by predators seeking live prey, or in the case of a predator to lure prey into approaching. For example, white-tailed deer fawns experience a drop in heart rate in response to approaching predators. This response, referred to as "alarm bradycardia", causes the fawn's
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colonies or near solitary fieldfares. In the absence of fieldfares, predation was greatest in the nests near the colonies. However, with fieldfares present, nest predation was higher in the nests near solitary fieldfares thus demonstrating the reduced predation resulting from communal defense.
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predation from great white sharks. Using decoy seals, the researchers varied the distance between the decoys to produce different domains of danger. The seals with a greater domain of danger had an increased risk of shark attack. This effect explains why animals will seek central positions in a
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is when animals living in a group "dilute" their risk of attack. The large group size serves as a type of concealment for any given individual in the group. If the animal is alone, a predator who spots the animal will directly aim its attack on the prey. However, if the animal is in a group, the
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The seal shark
Dalatias licha (aâc) and the wreckfish Polyprion americanus (dâf) attempt to prey on the hagfishes. First, the predators approach their potential prey. Predators bite or try to swallow the hagfishes, but hagfishes have already projected jets of slime (arrows) into the predatorsâ
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occurs when a large school of fish live together. One of the reasons we see this behavior in fish is because the larger the school of fish, the lower the probability that each individual fish is targeted. In fact, there are experiments that provide direct evidence for the decrease in individual
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is yet another advantage of group living in terms of predator deterrence on the individual level. Individuals living in large groups may be safer from attack because the predator may be confused by the large group size. As the group moves, the predator has greater difficulty focusing in on one
209:. These morphological and behavioral defense mechanisms most likely evolved due to predator and anti-predator adaptations . For a predator to locate a potential meal, it must first identify an organism as prey. Prey, however, have many adaptive characteristics which make such task difficult.
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has specialized glands on the tip of its abdomen that allows it to direct a toxic spray towards predators. The spray is generated explosively through oxidation of hydroquinones and is sprayed at a temperature of 100°C. This defense mechanism is highly successful at deterring predators.
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Shannon M. Murphy, Susannah M. Leahy, Laila S. Williams, and John T. Lill
Stinging spines protect slug caterpillars (Limacodidae) from multiple generalist predators. Behavioral Ecology (2010) 21 (1): 153-160 first published online November 26, 2009 doi:10.1093/beheco/arp166
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and defend against predators. Examples of structural adaptations include horns, claws, spikes, spines and teeth. Other animals use their appearance as a type of morphological defense to avoid being noticed by predators. This type of strategy includes camouflage and mimicry.
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that can be used by animals to either avoid predation or enhance predation. Predation risk has long been recognized as critical in shaping behavioral decisions. For example, this predation risk is of prime importance in determining time of evening emergence in echolocating
166:, experiences a learned aversion to the spined limacodid species and prefer to consume spineless larvae compared to the spined larvae when given the choice. Thus, the limacodidae larvae that are heavily armored with spines are more likely to survive predator encounters.
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Martin
Stevens, William TL Searle, Jenny E Seymour, Kate LA Marshall, Graeme D Ruxton (25 November 2011). "BMC Biology: Motion dazzle".Motion dazzle and camouflage as distinct anti-predator defenses. BMC Biology. pp. 9:81.doi:10.1186/1741-7007-9-81. Retrieved January 5,
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is when the animal jumps high with stiff legs and an arched back. This behavior is thought to be a honest signal of the gazelle's fitness in terms of its ability to outrun the predator that the predator evaluates when selecting which prey animal to pursue.
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Wade C. Sherbrooke, George A. Middendorf III, and M. E. Douglas (2004) Responses of Kit Foxes (Vulpes macrotis) to
Antipredator Blood-Squirting and Blood of Texas Horned Lizards (Phrynosoma cornutum). Copeia: August 2004, Vol. 2004, No. 3, pp. 652-658.
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Wade C. Sherbrooke, George A. Middendorf III, and M. E. Douglas (2004) Responses of Kit Foxes (Vulpes macrotis) to
Antipredator Blood-Squirting and Blood of Texas Horned Lizards (Phrynosoma cornutum). Copeia: August 2004, Vol. 2004, No. 3, pp. 652-658
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Morphological defenses involve structural adaptations such as horns, spikes, stingers, claws, fangs and toxins. Some morphological defenses utilize aspects of the prey's appearance to avoid detection. These strategies include camouflage and mimicry.
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occurs in group living because groups are able to detect predators sooner than solitary individuals. For many predators, success is dependent on surprise and if the prey is alerted too soon in an attack then it has an improved chance of escape.
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is able to shoot squirts of blood from its eyes if it feels threatened Texas horned lizard. Because an individual may lose up to 53% of blood in a single squirt , this rare example of autohemmorhaging is only against persistent canid predators,
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because they increase the fitness of the prey. The increase of fitness leads to a better reproductive success of the individual possessing the favorable trait, and thus results in the persistence of the trait in the population over time.
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There are a variety of other types of morphological features that species use in a similar way as spines to either deter predators or to defend against predators once under attack. These include teeth, claws, fangs, spikes and horns.
559:, a common predator. The male red colobus monkeys group together to place themselves between predators and the group's females and juveniles. The males act to jointly jump and bite the chimpanzees as an active form of defense.
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Jones, T. H., D. A. Clark, A. A. Edwards, D. W. Davidson, T. F. Spande, and R. R. Snelling. "The Chemistry of Exploding Ants, Camponotus SPP. (Cylindricus COMPLEX)." Journal of Chemical Ecology 30.8 (2004): 1479-492. Print.
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Many species have adapted behavioral strategies to avoid consumption and detection by predators. These strategies have evolved over time because they increase the lifespan, and thus the reproductive fitness of animals.
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Zintzen, Vincent, Clive D. Roberts, Marti J. Anderson, Andrew L. Stewart, Carl D. Struthers, and Euan S. Harvey. "Hagfish Slime as a Defense Mechanism against Gill-breathing Predators." Scientific Reports 1 (2011):
548:, the harassing of a predator by many prey animals, is common in birds, and is usually done to protect the young in social colonies. Numerous animals display mobbing behaviors to protect themselves from predators.
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shadow, self-decoration, cryptic behavior, or changeable skin pattern or color. Most methods contribute to camouflage by helping the animal hide against a background in order to avoid predation. Animals such as the
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Malte Andersson, Christer G. Wiklund, Clumping versus spacing out: Experiments on nest predation in fieldfares (Turdus pilaris), Animal Behaviour, Volume 26, Part 4, November 1978, Pages 1207-1212, ISSN 0003-3472,
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Some birds and insects use defensive regurgitation to ward off their predators. In theory, a predator will be much less likely to pursue their prey when it smells unappetizing, like vomit. Some birds, such as the
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Jones, T. H., Clark, D. A., Edwards, A., Davidson, D. W., Spande, T. F. and Snelling, R. R. 2004. The chemistry of exploding ants,Camponotus spp. (cylindricus complex). Journal of Chemical Ecology 30: 1479â1492.
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Daly M., Behrends P.R., Wilson M., Jacobs L. (1992) âBehavioural modulation of predation risk: moonlight avoidance and crepuscular compensation in a nocturnal desert rodent, Dipodomys merriamiâ. Animal Behavior
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Daly M., Behrends P.R., Wilson M., Jacobs L. (1992) âBehavioural modulation of predation risk: moonlight avoidance and crepuscular compensation in a nocturnal desert rodent, Dipodomys merriamiâ. Animal Behavior
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Peterson, Steven C., Nelson D. Johnson, and John L. LeGuyader. "Defensive Regurgitation of Allelochemicals Derived From Host Cyanogenesis By Eastern Tent Caterpillars." Ecology 68.5 (1987): 1268-272. Print.
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Lim, Jeanette, Douglas F. Fudge, Nimrod Levy, and John M. Gosline. "Hagfish Slime Ecomechanics: testing the gill-clogging mechanics." The Journal of Experimental Biology 209 (2006): 702-10. Print.
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Parejo D, AvilĂ©s JM, Peña A, SĂĄnchez L, Ruano F, et al. (2013) Armed Rollers: Does Nestlingâs Vomit Function as a Defence against Predators? PLoS ONE 8(7):e68862. doi:10.1371/journal.pone.0068862
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Smedley, Scott R., Elizabeth Ehrhardt, and Thomas Eisner. "Defensive Regurgitation by a Noctuid Moth Larva (Litoprosopus Futilis)." Psyche: A Journal of Entomology 100.3-4 (1993): 209-21. Print.
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are poisonous small molecules, peptides, or proteins that are produced in a living organism. The use of toxins by the prey further contributes to injuring the predator. For example, the
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Pursuit-deterrent signals are behavioral signals used by prey that apparently convince predators not to pursue them. A common example of this type of deterrence is seen in the gazelle.
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In a group, prey will seek central positions in order to reduce their domain of danger. Individuals along the outer edges of the group are more at risk of being targeted by the prey.
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Stanford, Craig B. âThe influence of chimpanzee predation on group size and anti-predator behavior in red colobus monkeys.â Animal Behavior. Volume 49, Issue 3, March 1995. 577-587
376:. Nocturnality may have evolved in these bats because of predation risk. Although early access during brighter times permits more food, it also leads to higher predation risk from
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Alboni, Paolo. Alboni, Marco. Bertorelle, Giorgio. (2008). The origin of vasovagal syncope: to protect the heart or to escape predation? Clinical Autonomic Research. 18(4):170-8.
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De Vos, A., O'Riain, J. "Sharks shape the geometry of a selfish seal herd: experimental evidence from seal decoys." Biology Letters. Volume 6, Number 1, February 2010. 48-50
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Behavioral defenses involve acts performed by the prey to avoid predation. These defenses include actions such as pursuit deterrent signals, nocturnality, and group living.
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Davidson, D.W., Salim, K.A. and Billen, J. 2011. Histology of structures used in territorial combat by Borneoâs âexploding antsâ. âActa Zoologica (Stockholm) 93: 487â491.
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Davidson, D.W., Salim, K.A. and Billen, J. 2011. Histology of structures used in territorial combat by Borneoâs âexploding antsâ. âActa Zoologica (Stockholm) 93: 487â491.
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Sherbrooke, W.C., 2001. Do vertebral-line patterns in two horned lizards (Phrynosoma spp.) mimic plant-stem shadows and stem litter? J. Arid Environ. 50, 109â120.
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are the most common type of morphological defense. This type of defense uses certain structural features of the species to avoid being consumed by the predator.
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Middendorf, George A., and Wade C. Sherbrooke. "Canid Elicitation of Blood-Squirting in a Horned Lizard (Phrynosoma Cornutum)." Copeia 2 (1992): 519-27. Print.
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Middendorf, George A., and Wade C. Sherbrooke. "Canid Elicitation of Blood-Squirting in a Horned Lizard (Phrynosoma Cornutum)." Copeia 2 (1992): 519-27. Print.
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Middendorf, George A., and Wade C. Sherbrooke. "Canid Elicitation of Blood-Squirting in a Horned Lizard (Phrynosoma Cornutum)." Copeia 2 (1992): 519-27. Print.
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A few species have developed some noteworthy morphological defense mechanisms against predators that stand out because of their bizarreness. For example, the
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Foster, W.A. & Treherne, J.E. (1981). "Evidence for the dilution effect in the selfish herd from fish predation on a marine insect." Nature, 295, 466-467.
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Predator deterrence can be divided into two major categories: morphological and behavioral defenses. Both of these types of defenses have evolved through
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Empirical evidence directly shows this decrease in predation for prey possessing this type of morphological defense. Many species of slug caterpillars,
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Warham, John. âThe Incidence, Functions and Ecological Significance of Petrel Stomach Oils.â New Zealand Ecological Society 24 (1977): 84-93. Print.
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Warham, John. âThe Incidence, Functions and Ecological Significance of Petrel Stomach Oils.â New Zealand Ecological Society 24 (1977): 84-93. Print.
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Duncan, P. & Vigne, N. (1979). "The effect of group size in horses on the rate of attacks by blood-sucking flies." Animal Behavior, 27, 623-625.
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H.Ronald Pulliam, On the advantages of flocking, Journal of Theoretical Biology, Volume 38, Issue 2, February 1973, Pages 419-422, ISSN 0022-5193,
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will regurgitate when disturbed by ants. Their vomit has repellent and irritant properties and is mostly effective at deterring predator attack .
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Shorter, J. R., and Olav Rueppell. "A Review on Self-destructive Defense Behaviors in Social Insects." Insectes Sociaux 59.1 (2012): 1-10. Print.
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Brian C.R. Bertram, Vigilance and group size in ostriches, Animal Behaviour, Volume 28, Issue 1, February 1980, Pages 278-286, ISSN 0003-3472,
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The dilution effect is seen in many instances in nature. One common example of the dilution effect is seen in the shoaling behavior of fish.
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susceptible to attack by the predator. This has allowed group living to persist in evolutionary history, as seen in the following examples.
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Finished writing a draft article? Are you ready to request review of it by an experienced editor for possible inclusion in Knowledge (XXG)?
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Nocturnality is an animal behavior characterized by activity during the night and sleeping during the day. This is a behavioral form of
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attack rate seen with group living. One example of a study that provide evidence for this dilution effect is in the observation of the
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Endler J.A. An overview of the relationships between mimicry and crypsis. Biological Journal of the Linnean Society (1981) 16:25-31
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Batesian and Mullerian. Both involve aposematic or warning signals to a predator, with the favored response to not be attacked. In
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Colt, H.B. (1940). Adaptive Coloration in Animal. Methuen, London. (Stick insects: p. 334-335. Bird Dropping spider, pp. 330-332.
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Duverge, P.L., Jones G, Rydell J., Ransome R. (2000) âFunctional significance of emergence timing in bats.â Ecography 23:32-40.
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Duverge, P.L., Jones G, Rydell J., Ransome R. (2000) âFunctional significance of emergence timing in bats.â Ecography 23:32-40.
96:. Throughout the animal kingdom, adaptations have evolved for every stage of this struggle in order to maximize prey survival.
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mouth. Choking, the predators release the hagfishes and gag in an attempt to remove slime from their mouth and gill chamber .
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is a sharp, needle-like anatomical structure used to inflict pain on predators. An example of this seen in nature is in the
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Another extreme predator deterrence behavior is observed in the Malaysian exploding ant. Social hymenoptera rely on
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Sherbrooke, WC (2003). Introduction to horned lizards of North America. University of California Press. pp. 117-118.
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Sherbrooke, WC (2003). Introduction to horned lizards of North America. University of California Press. pp. 117-118.
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is when prey groups are not just passive victims but actively defend themselves by attacking or mobbing a predator.
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many advantages group living has on decreasing the risk of predation, some of which include the ones listed below.
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Holmgren H and Enquist M. Dynamics of mimicry evolution. Biological Journal of Linnean Society (1999) 66:145-158.
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Holmgren H and Enquist M. Dynamics of mimicry evolution. Biological Journal of Linnean Society (1999) 66:145-158.
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is the ability of the organism to avoid observation or detection by other organisms. Methods of crypsis include
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384:. Therefore, they show an optimum evening emergence time that is a compromise between the conflicting demands.
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In a well-known study testing Hamilton's selfish herd effect, Alta De Vos and Justin O'Rainn (2010) studied
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802:(Pianka, Erika R., and Wendy L. Hodges. "Horned Lizards." The University of Texas. Web. 18 Nov. 2013. <
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Caro, T. M. (1986). "The functions of stotting in Thomson's gazelles: Some tests of the predictions".
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Thomas, Craig. Scott, Susan. All Stings Considered. (1997). University of Hawaii Press. p. 96-97.
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will regurgitate a droplet of digestive fluid to repel attacking ants. . Similarly, larvae of the
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but not to the group, because a larger group size makes the group more visible to predators.
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with flattened body, eliminating shadow to successfully camouflage into their surrounding
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Many of the structural adaptations animals use for defense also contain toxins.
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One common example of a structural adaptation to deter predators is a spine. A
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354:. Thanatosis is a form of bluff in which an animal mimics its own dead body,
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chance that the predator aims its attack to the same individual is reduced.
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Numerous insects utilize defensive regurgitation as well. For example, the
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An example of this type of predator deterrence is seen in the
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A Northern Fulmar chick protects itself with projectile vomit
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is an anti-predator adaptation developed over time through
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Another common example of the dilution effect is seen in
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Flying Fruit Bats at night as seen through a night camera
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areas of shadow there may be under the edge of the body.
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in Southern France. A type of parasitic fly, called the
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Another adaptation of nocturnality can be seen in the
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Another example of improved vigilance is within wild
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monkeys exhibit mobbing behavior when threatened by
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987:http://dx.doi.org/10.1016/0003-3472(78)90110-0
691:http://dx.doi.org/10.1016/0022-1910(77)90162-7
804:http://uts.cc.utexas.edu/~varanus/phryno.html
92:organisms in their constant struggle against
8:
38:. A user sandbox is a subpage of the user's
141:Stinging Limacodidae slugs, Megan McCarty65
892:A classificatory review of mimicry systems
896:Annual Review of Ecology and Systematics
516:
662:
7:
350:Another pursuit-deterrent signal is
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48:Create or edit your own sandbox
19:
525:is hard to catch amongst a herd
132:Structural Adaptation Defenses
1:
878:10.1016/S0003-3472(86)80052-5
296:Unique Morphological Defenses
71:Submit your draft for review!
44:not an encyclopedia article
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600:Unique Behavioral Defenses
584:flocks are preyed upon by
335:Pursuit-Deterrent Signals
188:Defenses using Appearance
634:Eastern tent caterpillar
118:Morphological Strategies
613:Defensive Regurgitation
389:File:Nocturnal Bats.jpg
241:Flat-tail Horned Lizard
223:Flat-tail Horned Lizard
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890:Pasteur, G. (1982). "
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302:Texas Horned Lizard
258:(bottom) exhibiting
234:is a type of visual
127:Structural Adaptions
503:Selfish herd theory
82:Predator deterrence
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574:Improved Vigilance
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511:Predator Confusion
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438:George C. Williams
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644:Suicidal Alturism
284:Mullerian mimicry
260:Mullerian mimicry
256:monarch butterfly
252:Viceroy butterfly
177:bombardier beetle
153:Sohal surgeonfish
101:natural selection
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551:For examples,
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466:water striders
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689:0022-1910,
582:wood pigeon
557:chimpanzees
553:Red colobus
382:bat falcons
268:camouflage
160:Limacodidae
901:: 169â199.
657:References
564:fieldfares
352:thanatosis
254:(top) and
231:Camouflage
199:camouflage
164:paper wasp
593:ostriches
521:A single
459:Horse-fly
378:Bat Hawks
94:predators
86:evolution
40:user page
29:the user
650:altruism
586:goshawks
498:group.
450:Shoaling
356:feigning
344:stotting
307:canidae
214:crypsis
27:This is
929:44:1-9.
730:44:1-9.
546:Mobbing
369:crypsis
341:Gazelle
291:mimicry
274:Mimicry
236:crypsis
203:mimicry
194:Crypsis
59:|
31:sandbox
845:Print.
205:, and
172:Toxins
966:2012.
531:zebra
523:zebra
806:>
440:and
380:and
374:bats
90:prey
50:here
894:".
874:doi
33:of
899:13
870:34
868:.
693:.
201:,
46:.
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989:.
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876::
52:.
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
