Examples of R-selected species are:
- Bacteria
- Oysters
- Weeds
- Mice
- Rabbits
- Jellyfish
- Dandelions
- Insects such as Mosquitoes, House flies, Daphnia and Goldenrod.
What does r selected species mean?
r-selected species, also called r-strategist, species whose populations are governed by their biotic potential (maximum reproductive capacity, r ). Such species make up one of the two generalized life-history strategies posited by American ecologist Robert MacArthur and American biologist Edward O. Wilson; K -selected species —that is, species whose population sizes fluctuate at or near their carrying capacity ( K )—make up the second strategy.
What animals are are strategists?
What are the six characteristics of an R-selected species?
- Rapid development.
- High reproductive rate.
- Early reproductive age.
- Small body size.
- One reproductive cycle.
- Short lifespan.
- Poor competitive ability.
- High mortality of offspring.
What are are and K species?
Typical examples of r-strategists are:
- Salmon
- Corals
- Bacteria
- Oysters
- Weeds
- Mice
- Rabbits
- Jellyfish
- Dandelions
- Insects such as Mosquitoes, House flies, Daphnia and Goldenrod
What is an are - selected organism?
- The r/k selection theory. The r/k selection theory proposes to explain the reproduction strategies of species with respect to their environmental characteristics.
- Survivorship curves. ...
- Conclusion. ...
What is an example of an R-strategist species?
Examples of r-strategist species are dogs, cats, insects, and fish.
What is an example of R and K selected species?
You can see r- and K-selected strategies clearly by looking at different organisms within a phylogenetic group, such as the mammals. For example, elephants are highly K-selected, whereas mice are much more r-selected. Among the fishes, most, like the salmon, are r-selected.
Which of the following is the best example of an r-selected species?
The R in R-selected represents population growth rate. Dandelions are particularly good examples of R-selected traits because they have several of the physical characteristics associated with R-selected traits including: rapid development, small size, and short lifespan.
Is a sea turtle R or K-selected?
Similarly, reptiles such as sea turtles display both r- and K-traits: although large organisms with long lifespans (should they reach adulthood), they produce large numbers of unnurtured offspring.
What is r-selected species in biology?
r-selected species are those that emphasize high growth rates, typically exploit less-crowded ecological niches, and produce many offspring, each of which has a relatively low probability of surviving to adulthood (i.e., high r, low K).
Are cats r-selected?
Cats and dogs are r-selected compared to humans, but K-selected compared to mice and rats. Mice and rats, in turn, are K-selected compared to most insects. We can think of an r-K selection continuum and an organism's position along it in a particular environment at a given instant in time (Pianka 1970).
What are r-selected species quizlet?
r-Selected Species. Early reproductive age. r-Selected Species. Most offspring will die before they reach the reproductive age.
Is a dandelion r-selected species?
Examples of r-selected species are marine invertebrates, such as jellyfish, and plants, such as the dandelion. Dandelions have small seeds that are dispersed long distances by wind; many seeds are produced simultaneously to ensure that at least some of them reach a hospitable environment.
Are rabbits R or K strategists?
How do rabbits breed? They fart out a ton of babies in a short period of time. In r and K selection theory, the rabbit is known as an r-strategist. R-strategists often live in unstable environments, so there's little chance that their offspring would survive into adulthood.
Are ants r-selected?
For example, ants can be considered r-selected. Plants such as dandelions are another good example of an r-selected species. The r/k selection theory should be thought of as a spectrum. Some organisms may produce a medium number of offspring but those offspring still grow quickly and the parents provide little care.
Are Crocodiles K-selected?
Some reptiles, like alligators and crocodiles, are also K-selected, living for a long time and laying eggs multiple times. Some even provide early parental care over their eggs and offspring.
Are gorillas K-selected species?
Examples of animals that pursue K strategies are gorillas and whales. The largest of the primates, gorillas require specialized diets (with distinct differences in the diets of mountain and lowland gorillas) and produce a single offspring once every three to four years.
Which animals are a r-selected species?
R-selected animals are those that produce large numbers of offspring at a time. Examples include frogs, most insects, and salmon.
What is the difference between r- and K-selected species?
R-selected species have populations that fluctuate wildly as a result of high birth rates followed by high mortality rates. K-selected species have...
What is an example of K-selected species?
K-selected species are typically large, produce few offspring at a time, and have long lives. Examples include elephants, whales, and alligators.
Are humans r-selected species?
Humans are not r-selected species. Because they provide high levels of parental care, produce few offspring at a time, and live long lives they are...
What is the difference between a k and a r selected species?
The progeny number in case of r selected species is high whereas K selected species, parental care is low in r selected species and high in K selected species, and the early mortality is high in r selected species as compared to K selected species. Also, the lifespan is short for r selected species and long for K selected species.
Why are R selected species less likely to survive?
The offsprings have less probability of surviving to adulthood owing to several environmental conditions. The characteristics of r selected species prove them dominant species in the unpredictable or unstable environment because of their ability for rapid reproduction. Although high in number, the r selected population are less likely ...
Which species produces a higher number of progenies or offsprings but offers less parental care?
The r-selected species are the species that produce a higher number of progenies or offsprings but offer less parental care i.e. less individual parental investment, whereas the K-selected species produced less offspring or number of progenies but providing more parental care or parental investment to each individual.
Why is early onset of maturity required in R selected species?
Because of the large numbers of offspring, they are unable to invest high amounts of parental care to each individual and therefore, early onset of maturity is required in the r selected species. Examples of these kinds of species include mosquitos, rats, and bacterias. On the other hand, k selected species are characterised by complex biology, ...
What are the characteristics of a R species?
The traits that are important for the characteristics of r selected species include high ability to reproduce i.e. high fertility rate, small body size, early onset of maturity, short time of generation, and the capability to disperse off the progeny widely. R strategists are usually the primary colonisers, especially in areas ...
What is an R strategist?
R strategists are usually the primary colonisers, especially in areas of major ecological disruption such as regions surrounding volcanic eruptions. They are followed by a succession of increasingly competitive flora and fauna.
Do R selected populations mature early?
Hence, because of this, the offsprings or progenies in an r selected population even mature early as compared to the K selected population. In some of the r selected species examples, it is observed that after the birth of progenies or laying of eggs, the parent usually leaves them off and goes on to live their lives accordingly.
What is an R-selected species?
r-selected species, also called r-strategist, species whose populations are governed by their biotic potential (maximum reproductive capacity, r ). Such species make up one of the two generalized life-history strategies posited by American ecologist Robert MacArthur and American biologist Edward O.
Why are some populations, called R-selected, considered opportunistic?
Some populations, called r -selected, are considered opportunistic because their reproductive behaviour involves a high intrinsic rate of growth ( r )—individuals give birth once at an early age to many offspring. Populations that exhibit this strategy often have been shaped by an extremely variable and uncertain environment. Because mortality occurs…
Why are some populations considered opportunistic?
Some populations, called r -selected, are considered opportunistic because their reproductive behaviour involves a high intrinsic rate of growth ( r ) —individuals give birth once at an early age to many offspring.
What Is R-Selected vs. K-Selected?
A species' life history strategy is the way that it survives and reproduces. The life history theory attempts to explain and understand how the processes of evolution have led to the amazing diversity of life history strategies observed on Earth. Life history strategies can divide organisms in several ways.
R and K Strategies and Traits
Both r and K strategies result in similar characteristics in the organisms that utilize them. Below, investigate how both r- and K-selected species often exhibit characteristics specific to their selection type.
What is an R selected species?
R-selected species are those that favor a large number of offspring. This includes animals like insects, amphibians, many fish, and reptiles. They tend to be smaller organisms so the energy used to make each individual is low and live in environments that are unstable.
Why are species r-selected?
It is also important to note that evolution is what caused species to be r-selected or K-selected. Unstable environments favored a large number of offspring, as investing a large amount of energy into the offspring produced little return. However, in a stable environment offspring are more likely to survive with large parental investment.
What is the R selection of an animal?
R-selected and K-selected species are terms that biologist use to describe the reproductive strategy of animals. Either an animal produces a large number of offspring and it basically is a numbers game for those offspring or the animals have few offspring and invest a large amount of time in those offspring. R-selected species are those that favor a large number of offspring. This includes animals like insects, amphibians, many fish, and reptiles. They tend to be smaller organisms so the energy used to make each individual is low and live in environments that are unstable. They also have shorter lifespans and reach sexual maturity quickly. They have type III survivorship pattern which means that earlier in life more organisms will die than later on in their life. In these species, the number of offspring is important because it directly impacts the population size.
Which family of animals tends to fall towards the R-selected side of the scale?
Members of squamate (large lizards and snakes) and Cricetidae (a rodent family) tend to fall more towards the r-selected side of the scale, therefore, the number of offspring plays a large role in the population size. It is also important to note that evolution is what caused species to be r-selected or K-selected.
Why do organisms have to make trade-offs between reproduction and survival?
Since there are not unlimited resources organisms must make trade-offs between reproduction and survival. For example, an organism can grow to a larger mass and then reproduce or it can reproduce at a smaller size and produce less viable offspring or fewer offspring.
What Are R-Selected Species?
Examples of R-Selected Species
A Brief Explanation of R-Selected Species
- In the r selected species, the r can be said to be a reference to reproduction. The r strategist species are the ones that are said to be dependent on quantity over quality for the propagation of their genes over generations. In the evolutionary processes, the r strategist finds an advantage in the survival factor because of sheer numbers. If the numbers are more, then even under advers…
R Selected Species Examples
- There are many r selected species examples among which the most common ones are the rodents or rats. They are the most common and relatable species that is best to explain the concept of r selected species. Rats produce a number of progenies and then after tending them for a few days they disperse off their offspring. Also, they have the qualitative traits that define t…
Other R Selected Species Examples Include The Following
- The most common species of organisms that can be found almost anywhere on Earth is bacteria. A bacterial species is the best example of the r selected species. Diatoms are a group of algae or more specifically microalgae, and are found in oceans, waterways, and soils of the world. They are also r selected species. In arthropods, insects are one of ...