What are the characteristics of R selected species?

The production of numerous small offspring followed by exponential population growth is the defining characteristic of r-selected species. They require short gestation periods, mature quickly (and thus require little or no parental care), and possess short life spans.

In this way, what is a K selected species?

K-selected species possess relatively stable populations and tend to produce relatively low numbers of offspring; however, individual offspring tend to be quite large in comparison with r-selected species. In this equation N is the number of individuals in the population, t is time, and r is the biotic potential.

What does K selected mean?

selection occurring when a population is at or near the carrying capacity of the environment, which is usually stable: tends to favor individuals that successfully compete for resources and produce few, slowly developing young, and results in a stable population of long-lived individuals.Compare r selection.

What is an example of an R selected species?

Typical examples of r-species are mice, rabbits, weeds and bacteria, which have a lot of offspring, but a short life expectancy. Examples of organisms undergoing K-selection are tortoises, elephants, people, and sequoia trees: their offspring are few but long-lived.

Are fish r selected species?

There are also animals that have the R-selected characteristics. Many aquatic organisms like some species of fish, frogs, and salamanders have relatively short lifespans, reach sexual maturity rapidly, and reproduce by releasing hundreds of eggs with only a few surviving to adulthood.

What are the biotic and abiotic factors that limit population size?

The environment limits population growth by changing birth and death rates. The factors affecting population size and growth include biotic factors such as food, disease, competitors, and predators and abiotic factors such as rainfall, floods, and temperature.

How biodiversity is of direct economic value?

It is useful to consider biodiversity-induced changes in human wellbeing using the concept of ‘total economic value’. Specifically, wellbeing is defined in terms of the different types of value that individuals derive from biodiversity. The first category of value is known as ‘direct use’ value.

Are predator prey relationships density dependent?

As the predator eats more prey, the prey population size decreases. This, in turn, decreases predation, as well as the population size of the predator. As predation decreases, the prey population size increases and once again provides more prey for the predator. Competition is another density-dependent factor.

What are some examples of K selected species?

In this equation N is the number of individuals in the population, t is time, and r is the biotic potential. Examples of K-selected species include birds, larger mammals (such as elephants, horses, and primates), and larger plants.

What is an example of an R selected species?

Typical examples of r-species are mice, rabbits, weeds and bacteria, which have a lot of offspring, but a short life expectancy. Examples of organisms undergoing K-selection are tortoises, elephants, people, and sequoia trees: their offspring are few but long-lived.

What does K selected mean?

selection occurring when a population is at or near the carrying capacity of the environment, which is usually stable: tends to favor individuals that successfully compete for resources and produce few, slowly developing young, and results in a stable population of long-lived individuals.Compare r selection.

What is an R selected species?

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).

How do reproductive strategies differ?

Reproductive and Survivorship Strategies. It may come as no surprise to you that different organisms have different strategies for reproduction. At one extreme, some organisms produce a huge number of offspring once in their lifetime and then die or never reproduce again.

What is the R strategist?

Bacterial Growth Curve representing r and K Reproductive Strategies. Those organisms described as r-strategists typically live in unstable, unpredictable environments. Here the ability to reproduce rapidly (exponentially) is important.

What does the K in K strategists stand for?

K-strategy relates to the carrying capacity of an habitat or a niche (K stands for Kapazit├Ąt, which is the German word for capacity).

What does the K in K selected species come from?

“r” stands for “rate” {growth rate}, r strategists have a high r value and a low K value. They grow fast but most die. “K” stands for Kapazit├Ątsgren which is german for capacity limit, now called carrying capacity, K strategists have a low r and a high K. They grow slow but more survive.

Why are K selected species more vulnerable to extinction?

Ecologists refer to organisms at the first of these two extremes (those adapted to unstable environments) as r-selected. K-selected species are more prone to extinction than r-selected species because they mature later in life and have fewer offspring with longer gestation times.

Can the human population grow indefinitely?

Human population, now over 7 billion, cannot continue to grow indefinitely. There are limits to the life-sustaining resources earth can provide us. In other words, there is a carrying capacity for human life on our planet. Carrying capacity is the maximum number of a species an environment can support indefinitely.

What is the K strategy?

The two evolutionary “strategies” are termed r-selection, for those species that produce many “cheap” offspring and live in unstable environments and K-selection for those species that produce few “expensive” offspring and live in stable environments.

Are oak trees K strategists?

The oak tree, like other k-strategists, develop in stable environments where their species population remains at stable numbers. K-strategists take longer to mature than r-strategists, and produce fewer offspring, this is because they do not need their population to adapt so quickly because the environment is stable.

What is a survivorship curve?

A survivorship curve is a graph showing the number or proportion of individuals surviving to each age for a given species or group (e.g. males or females). They are typical of species that produce few offspring but care for them well, including humans and many other large mammals.

What is an example of a density dependent factor?

The density dependent factors are factors whose effects on the size or growth of the population vary with the population density. There are many types of density dependent limiting factors such as; availability of food, predation, disease, and migration. However the main factor is the availability of food.

What is Independent density?

Density-independent factors, such as weather and climate, exert their influences on population size regardless of the population’s density. In contrast, the effects of density-dependent factors intensify as the population increases in size.