Predator–Prey Relationships | gtfd.info
The prey is the organism which the predator eats. Some examples of predator and prey are lion and zebra, bear and fish, and fox and rabbit. The words. How do these interactions create dynamic, ever-changing biological systems? Aa Aa Aa Predation influences the fitness of both predators and prey. Predation is a biological interaction where one organism, the predator, kills and eats another Sometimes predator and prey find themselves in an evolutionary arms race, a cycle of adaptations and counter-adaptations. methods; and some relationships that result in the prey's death are not generally called predation.
This is because the pursuit requires energy. A predator that continually pursues prey without a successful kill will soon become exhausted and will be in danger of starvation. Predatory species such as lions are typically inactive during the hot daytime hours, when prey is often also resting, but become active and hunt at night when conditions are less energy taxing and prey is more available. Similarly, bats emerge at night to engage in their sonar-assisted location of insects that have also emerged into the air.
When supplied with food in a setting such as a zoo, predators will adopt a sedentary lifestyle. Predation is an energy-consuming activity that is typically done only when the creature is hungry or to supply food for offspring. In settings such as an aquarium, predators and prey will even co-exist. Being a prey does not imply that the creature is completely helpless. The prey may escape from the predator by strategies such as mimicry, or can simply outrun or hide from the predator.
Some species act coordinately to repel a predator. For example, a flock of birds may collectively turn on a predator such as a larger bird or an animal such as a cat or dog to drive off the predator. This mobbing type of repulsion can be highly orchestrated. As well, some bird species use different calls, which are thought to be a specific signal to other birds in the vicinity to join the attack.
Even birds of a different species may respond to such a call. The fluctuation in the numbers of a predator species and its prey that occurs over time represents a phenomenon that is known as population dynamics. The dynamics can be modeled mathematically. The results show that a sharp increase in the numbers of a prey species an example could be a rabbit is followed soon thereafter by a smaller increase in numbers of the relevant predator in this case the example could be the fox.
As the prey population decreases due to predator killing, the food available for the predators is less, and so their numbers subsequently decline.
With the predator pressure reduced, the numbers of the prey can increase once again and the cycle goes on. The result is a cyclical rising and falling of the numbers of the prey population, with a slightly later cyclical pattern of the predator.
A famous predator-prey model is the Lotka-Volterra version. The two equations were formulated in the mids by Italian mathematician Vito Volterra — to explain the decline in a fish population observed in the Adriatic Sea during World War I — At the same time, American mathematician Alfred Lotka — was using the equations to explain the behavior of some chemical reactions. Their efforts were recognized as the Lotka-Volterra model, which represents one of the first examples of ecological modeling.
Other examples include the Kermack-McKendrick model and the Jacob-Monod model used to model predation of one bacterial species on another.
Impacts and Issues Predator-prey relations are an important driving force to improve the fitness of both predator and prey. In terms of evolution, the predator-prey relationship continues to be beneficial in forcing both species to adapt to ensure that they feed without becoming a meal for another predator.
This selection pressure has encouraged the development and retention of characteristics that make the individual species more environmentally hardy, and thus collectively strengthens the community of creatures that is part of various ecosystems.
For example, lions that are the fastest will be most successful in catching their prey. Over time, as they survive and reproduce, the number of fast lions in the population will increase.
Similarly, the superior attributes that enable prey species to survive will be passed on to succeeding generations. Over time, the fitness of the prey population will also increase. Left to operate naturally, the predator-prey relation will be advantageous for the fitness of both species in relation to how they compete against other species in the same ecosystem.
However, since each species improves, their relationship with each other remains unchanged, and the challenge remains to kill or escape from being killed.
The fossil record of Hederellids, which date back almost million years, indicate that the survival race between predator and prey has been a driver of evolution perhaps since evolution began. If so, the predator-prey relationship is fundamentally important to life on Earth.
Predator-prey relationships are also vital in maintaining and even increasing the biological diversity of the particular ecosystem, and in helping to keep the ecosystem stable. This is because a single species is kept under control by the species that uses it for food. Without this population check, a species such as a rabbit could explode in numbers, which can destroy the ability of the ecosystem to support the population.
Solitary predators have more chance of eating what they catch, at the price of increased expenditure of energy to catch it, and increased risk that the prey will escape. These include speed, agility, stealth, sharp senses, claws, teeth, filters, and suitable digestive systems. Many predators have acute hearing, and some such as echolocating bats hunt exclusively by active or passive use of sound.
Some predators such as snakes and fish-eating birds like herons and cormorants swallow their prey whole; some snakes can unhinge their jaws to allow them to swallow large prey, while fish-eating birds have long spear-like beaks that they use to stab and grip fast-moving and slippery prey. Lions can attack much larger prey, including elephants, but do so much less often.
Predation - Wikipedia
Predators are often highly specialized in their diet and hunting behaviour; for example, the Eurasian lynx only hunts small ungulates. When prey have a clumped uneven distribution, the optimal strategy for the predator is predicted to be more specialized as the prey are more conspicuous and can be found more quickly;  this appears to be correct for predators of immobile prey, but is doubtful with mobile prey.
This has led to a correlation between the size of predators and their prey. Size may also act as a refuge for large prey. For example, adult elephants are relatively safe from predation by lions, but juveniles are vulnerable. Members of the cat family such as the snow leopard treeless highlandstiger grassy plains, reed swampsocelot forestfishing cat waterside thicketsand lion open plains are camouflaged with coloration and disruptive patterns suiting their habitats.
Female Photuris firefliesfor example, copy the light signals of other species, thereby attracting male fireflies, which they capture and eat. Venom and Evolution of snake venom Many smaller predators such as the box jellyfish use venom to subdue their prey,  and venom can also aid in digestion as is the case for rattlesnakes and some spiders. These changes are explained by the fact that its prey does not need to be subdued.
Antipredator adaptation To counter predation, prey have a great variety of defences. They can try to avoid detection. They can detect predators and warn others of their presence.
In this snowy environment, the polar bear is white to avoid being noticed as it approaches the seal, and the seal pup is white to avoid being noticed by the bear. The fastest lions are able to catch food and eat, so they survive and reproduce, and gradually, faster lions make up more and more of the population.
The fastest zebras are able to escape the lions, so they survive and reproduce, and gradually, faster zebras make up more and more of the population. An important thing to realize is that as both organisms become faster to adapt to their environments, their relationship remains the same: This is true in all predator-prey relationships. Another example of predator-prey evolution is that of the Galapagos tortoise.